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FREE ORAL SESSIONS Oral Session I – Monitoring O-01 O-02 Capnogram third-phase-slope: a “guideline” in respiratory therapy? Combined monitoring of ...

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FREE ORAL SESSIONS Oral Session I – Monitoring O-01

O-02

Capnogram third-phase-slope: a “guideline” in respiratory therapy?

Combined monitoring of functional residual capacity and compliance in cardiac patients with respiratory failure: effect on right ventricular function

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Barna Babik , Tamas Nagy , Tunde Ivanyi , Gabor Bogats , 2 Ferenc Petak 1

Department of Anaesthesiology and Intensive Therapy, 2 University of Szeged, Szeged, Hungary, Department of Medical Informatics, University of Szeged, Szeged, Hungary, 3 Department of Cardiac Surgery, University of Szeged, Szeged, Hungary Introduction. The phase III slope of the capnogram (pIIICO2) represents the progressive emptying of the alveoli, and it reflects ventilation/perfusion mismatch and ventilation inhomogeneity. Although pIIICO2 has also been shown to correlate with spirometric indices, the relationship of this parameter to the airway properties has not been systematically evaluated. Therefore, we investigated whether the pIIICO2 reflects changes in the airway resistance and thus, to establish its monitoring value to follow changes in airway properties during mechanical ventilation. Method. Side-stream capnography was performed during mechanical ventilation (descending flow, f = 12-14/min, FiO2 = 0.5, VT = 7 ml/kg) in patients undergoing elective cardiac surgery (n = 18, 46-79 years). The pIIICO2 was expressed as a slope, i.e. the changes of partial CO2 pressure of the exhaled gas per unit time from the 15-s CO2 traces digitized and stored on a computer. The tracheal flow (V’) and airway opening pressure (Pao) were also measured in 15-s apnoeic periods, during which small-amplitude pseudorandom oscillations (between 0.4-6 Hz) were introduced into the trachea. The input impedance spectra of the respiratory system (Zrs) were calculated as Zrs=Pao/V’. The airway resistance (Raw) was assessed from the real part of Zrs by model fitting. Successive pIIICO2 and Raw estimates were performed preoperatively under intact chest condition with PEEP levels of 3, 6 and 9 cmH2O, and after sternotomy at a PEEP of 3 cmH2O. Results. Increasing PEEP in the intact chest led to regular decreases in both pIIICO2 (1.9±0.4[SE] and 1.4±0.3 mmHg/s for PEEP 3 and 9, respectively; P<0.05) and Raw (2.5±0.5 and 1.7±0.4 cmH2O.s/l; P<0.05). Chest opening led to further simultaneous decreases in both pIIICO2 (0.7±0.2 mmHg/s) and Raw (1.1±0.2 cmH2O.s/l). The analyses of the capnographic and forced oscillatory parameters obtained at PEEP 3 in the intact chest revealed strong correlation between the initial levels of 2 Raw and the pIIICO2 (R =0.88, P<0.0001). Increasing PEEP in the intact chest resulted in parallel decreases in both pIIICO2 and Raw, which resulted in an excellent association between 2 these indices (R =0.87, P<0.0001). Discussion. These findings demonstrate that changes in pIIICO2 are sensitive to alterations in airway calibre. Therefore, monitoring of pIIICO2 may have a value for bedside monitoring of the airway properties during mechanical ventilation.

Franco Turani, Livia Cococcia, Mauro Falco, Federica Mounayergi, Flavio Gargano, Valerio Nicoletti, Federico Candidi, Riccardo Barchetta European Hospital, Rome, Italy Introduction. Mechanical ventilation of ARDS patients requires adequate levels of PEEP to recruit atelectatic areas, avoiding either hyperinflation or cardiac depression. The aim of this study was to evaluate the FRC by a modified nitrogen multiple washout technique (NMBW) combined with the study of Crs, secondly, to set best PEEP on data of FRC and compliance respiratory system (Crs), and thirdly, to evaluate by an echocardiography study, the cardiac response to different levels of PEEP. Method. Thirty patients with ALI/ARDS were ventilated with an Engstrom carestation ventilator (GE Health Care) according to the ARDS net guidelines. FRC measurement was carried out with the COVX module integrated within the ventilator (GE Healthcare, Helsinki, Finland) by a NMBW technique. Every patient had a basal FRC measurement and then three measurements at PEEP 15, 10 and 5 cmH2O during a derecruiting manoeuvre. At every step we studied the changes of FRC, Crs, PaO2/FIO2 ratio and performed transoesophageal echocardiography (Agilent 5500 H P) to evaluate the integral of velocity time of right ventricular outflow tract (RVOT VTI) and stroke volume (SV) through the main PA. All data are reported as mean ±SD. ANOVA test was used to compare changes during the time. Results. Table 1 shows the main results of the study. Best PEEP was set at 10 cmH2O at which level the decrease of FRC and improvement of Crs indicated the start of de-recruitment and end of over-distension. FRC mL Crs mL/cmH2O PaO2 / FIO2 RVOT VTI cm SVI mL/m2

PEEP 15

PEEP 10

PEEP 5

2975±644 33±8 310±62 24±2 34±2.1

2412±585* 39±9* 291±78 25±3 35±3.5

2059±556** 45±10** 185±89# 26.7±6 37±1.5*

*P<0.05, **P<0.01 vs. PEEP 15, # P<0.001 vs. PEEP 15 and 10.

Conclusions. 1. Increased levels of PEEP improved FRC. 2. Combined monitoring of FRC and Crs may detect hyperinflation. 3. Hyperinflation may depress right ventricular function. Reference. 1. Lambermont B. Ghuysen A, Janssen N, et al. Comparison of functional residual capacity and static compliance of the respiratory system during a positive end-expiratory pressure (PEEP) ramp procedure in an experimental model of acute respiratory distress syndrome. Crit Care 2008; 12: R91.

Supported by OTKA grant K62403

Journal of Cardiothoracic and Vascular Anesthesia, Vol 24, No 3S (June Supplement), 2010: pp S1-S35

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O-03 Haematocrit measurement by conductivity underestimates haematocrit in haemodiluted cardiac surgery patients Reto Basciani, Franziska Amiet, Jolanda Consigio, Gabor Erdös, Balthasar Eberle University Hospital Bern, Inselspital, Bern, Switzerland Introduction. Accurate and precise haematocrit (Hct) measurement is crucial for perioperative transfusion decisions. In our institution, point-of-care Hct is measured during cardiac surgery and CPB either by CO-oximetry (ABL 825 Flex) or by conductivity (GEM Premier 3000). In daily practice, suspicion for bias in haemodiluted patients emerged. The aim of our study was therefore to compare accuracy of 3 different systems for Hct measurement with reference Hct. Method. Serial arterial blood samples (n=113) of 44 patients undergoing cardiac surgery with CPB were drawn into gas tight syringes (Safe Pico), de-aired, and analysed immediately in 4 systems (GEM Premier 3000; GEM Premier 4000; ABL 825 Flex; centrifugation in the central laboratory = reference Hct). Analysers were calibrated according to manufacturers’ instructions by laboratory technicians. Agreement between methods was determined according to Bland and Altman for all samples, as well as for subgroups with reference Hct <27% and •27% (between-subgroup comparison: Mann-Whitney U-test). Results. Differences (mean ±SD) from reference Hct are summarized in the table. Subgroups with reference Hct <27% and •27% differ significantly in their bias with all 3 systems (P<0.001).

All samples Hct > 27% Hct ” 27%

GEM 3000 GEM 4000 ABL 825 difference from reference haematocrit (mean ± SD) -1.0 ± 2.2 -1.2 ± 3.9 +1.3 ± 1.7 -0.1 ± 1.8 +0.2 ± 1.7 +0.6 ± 1.6 -2.1 ± 1.6 -1.8 ± 1.5 +2.1 ± 1.2

Discussion. Measurement of haematocrit by the conductivity method using the GEM Premier 3000 and 4000 underestimates Hct systematically in haemodiluted patients, e.g., during and after CPB. Clinically, this may lead to unwarranted RBC transfusion. CO-oximetry-based ABL 825 systematically overestimates Hct. Devices for haematocrit measurement based on conductivity may not be suitable for the use in patients haemodiluted to a level around the trigger Hct for RBC transfusion. O-04 Syngo Dyna CT: an intraoperative real time 3D CT scan for transapical (TA) aortic valve implantation in Hybrid OP: Initial Leipzig experience Chirojit Mukherjee, Eugen Krohmer, Joergen Banusch, Heinz Tschernich, Aniruddha Janai, Thomas Walther, Fredreich Wilhelm Mohr, Jörg Ender Heartcenter Leipzig, Leipzig, Germany Introduction. Implantation of transapical aortic valves is routinely performed under control of fluoroscopy and transoesophageal echocardiography. Using multi axis Artis Zeego system (Siemens AG,Deutschland) in association with our cardiac imaging section, syngo Dyna CT has been devised to provide an advanced imaging technique for better implantation of the TA valve. Method. Insertion of a pigtail catheter into the aortic root is followed by an injection of 20 mL of diluted contrast medium

(1:3) into the aortic root. Images are acquired through rotational angiographic scan using rapid ventricular pacing (RVP). Images acquired are then processed in the imaging work station using single slices for 3D reconstruction. 3D volume is processed for segmentation of aortic root and coronary ostia. C-arm angulation is achieved using the 3D image coordination and initiation of overlay mode. Syngo i-pilot software is used to overlay the images obtained from 3D Dyna CT and fluoroscopy. Balloon dilatation is followed with exact positioning of the valve under rapid ventricular pacing. Results. Forty three patients have undergone this 3D dyna CT for deployment of the valve, without occlusion of coronary ostium. In 3 patients a very minimal paravalvular leak was detected. The patients tolerated this extra episode of RVP and contrast medium well. The image overlay technique allows accurate measurements for distance of the coronaries from the annulus and accurate measurement of the annulus itself, which assures optimal implantation of the valve during the beating heart. Conclusions. Intraoperative Syngo Dyna CT is a promising imaging technique for further accuracy in implanting the TA aortic valve and is a helpful additional tool to real time 3D echo and fluoroscopy. Being an intraoperative procedure it is essential for the anaesthesiologist to understand and interpret the basic mechanisms. Further studies are required to validate it as a routine intraoperative procedure. Reference. 1. Kempfert J, Falk V, Schuler G, et al. Dyna-CT during minimally invasive off-pump aortic valve implantation. Ann Thorac Surg 2009; 88: 2041. O-05 Sublingual microcirculatory density altered during cardiopulmonary bypass

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Andrea Vignali1, Giampaolo Martinelli1, Rob Meakin3, Heyman 2 Luckraz 1

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Department of Cardiothoracic Anaesthesia, Department of 3 Cardiothoracic Surgery, Department of Medical Physics and Clinical Engineering, Heart & Lung Centre Wolverhampton, United Kingdom Introduction. Development of post-operative complications after cardiac surgery, such as multiple organ failure, may be related to impaired microcirculatory perfusion as a result of systemic inflammation. Cardiopulmonary bypass (CPB) assisted cardiac surgery is associated with activation of inflammatory mediators and SIRS. The advent of modern imaging modalities such as Sidestream Dark Field (SDF) imaging, has facilitated the observation of the human microcirculation at the bedsides in real time. Method. From July to September 2009, 40 SDF imaging was carried out in 10 consecutive patients undergoing cardiac surgery with the use of CPB. The microcirculation was studied using SDF imaging (Microscan: Microvision Medical, Amsterdam, NL). The clips obtained were analysed for Microvascular Flow Index (MFI) and De Backer density score with AVA 3.0 software (Automated Vascular Analysis, AMC Amsterdam). Serial SDF clips were recorded at T0 = pre-CPB, T1 and T2 = early and late phase (rewarming) of CPB, T3 = in ITU and T4 = first postoperative day. Result. The mean capillary density measured according to De Backer, decreased significantly during CPB: from 11.06 ± 2.03 to 9.12 ± 1.43 (T1 vs. T0 P<0.05) and decreased further to 8.97 ± 1.65 in T2; values returning to normal at T3: 10:59 ± 1.7. MFI did not show significant changes. Lactate increased significantly at T4 (T4 vs. T0 P<0.05). No correlation between De Backer score changes with haemodynamics, respiratory variables,

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lactate, acid-base equilibrium, SvO2, haemodilution or hypothermia was observed. Conclusion. SDF imaging could be used as a technique to evaluate microcirculatory changes at the bedside as well as in the operation theatre. Microcirculatory density alterations were observed during CPB assisted cardiac-surgery. These

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alterations are independent from systemic perfusion and changes of other variables. We hypothesize that impaired sublingual perfusion during cardiac surgery may be a predictor of postoperative lactate rise. Early detection of impaired microcirculation could identify patients at risk of developing organ dysfunction after cardiac surgery.

Oral Session II – Cardiopulmonary Bypass O-06

O-07

Best pump flow during cardiopulmonary bypass 1 2 Sisse Anette Thomassen , Anders Larsson , Jan Jesper 1 1 1 Andreasen , William Bundgaard , Bodil Steen Rasmussen

Effect of different CPB modalities on endothelial function in adult cardiac surgery patients

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Departments of Anaesthesia and Cardiothoracic Surgery, Centre for Cardiovascular Research, Aalborg Hospital, Aarhus 2 University Hospital, Aalborg, Denmark, Department of Anaesthesiology and Intensive Care, Uppsala University, Uppsala, Sweden Introduction. Blood flow during normothermic cardiopulmonary bypass (CPB) is calculated and based on the patient’s body -1 -2 surface area (BSA) [1], i.e., 2.2-2.5 litre min m [2]. Higher comorbidity, age and weight of the patients scheduled for today’s cardiac surgery question this calculation of blood flow during CPB as it may not reflect the individual metabolic requirement. The hypothesis of the present study was that a measured cardiac output (CO) prior to CPB is a better estimate of an optimal blood flow during CPB. Method. Twenty-two elective adult cardiac surgery patients with left ventricular ejection fraction >50%, no history of cerebral insult, head trauma or verified carotid artery stenosis, were included. A randomized cross-over study was performed with random allocation to a CPB blood flow for 20 min based on either the calculated flow (2.4 litre min-1 m-2) or the individual measured CO prior to CPB, and switch to the alternative blood flow for another 20 min. The CO was measured by a pulmonary artery catheter. The effect parameters were cerebral oxygenation measured by near infrared spectroscopy, mixed venous saturation, base excess and lactate concentration. Results. The calculated CPB blood flow was kept at 2.4 litre -1 -2 min m , while the blood flow based on the measured CO -1 -2 -1 -2 varied from 1.9 to 3. litre min m (median 2.4 litre min m ). No differences were seen in the effect parameters; cerebral oxygenation (P=0.26), mixed venous saturation (P=0.57), base excess (P=0.26), and lactate (P=0.73). Discussion. A CPB blood flow based on an individual estimate did not improve cerebral and global oxygenation compared to a blood flow based on BSA. References. 1. Boyd E. The growth of the surface area of the human body. University of Minnesota, 1935. 2. Murphy GS, Hessel II EA, Groom RC. Optimal perfusion during cardiopulmonary bypass: An evidence-based approach. Anesth Analg 2009; 108: 1374-1417.

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Fabio Sangalli , Marco Guazzi , Silvia Senni , Wilma Sala , 1 1 Leonello Avalli , Roberto Fumagalli 1

Dipartimento di Medicina Perioperatoria e Terapia Intensiva, 2 Ospedale San Gerardo, Monza, Italy, Unità Cardiopolmonare, Università degli Studi di Milano, Ospedale San Paolo, Milano, Italy Introduction. The aim was to investigate the influence of CPB on endothelial function of adult cardiac surgical patients and to evaluate the effect of the different modalities of continuous-flow CPB (CF-CPB), pulsatile-flow CPB (PF-CPB), and beating heart surgery (OPCAB). Method. We enrolled 36 adult patients scheduled for elective cardiac surgery. Endothelial function was investigated noninvasively through the evaluation of the flow-mediated dilation (FMD) of the brachial artery, according to published guidelines [1] just after induction of general anaesthesia. Patients with an impaired endothelial function at baseline were excluded from further analysis. Patients were subsequently divided into three groups according to the CPB modality used: CF-CPB (10 pts.), PF-CPB (10 pts.), and OPCAB (8 pts.). FMD of the brachial artery was re-evaluated on admittance in the ICU, and 24 hours thereafter. Results. FMD of the brachial artery was abolished in 8/36 patients (22%). Baseline endothelial function did not differ in the three groups. FMD (%) in the perioperative period is shown in the figure. 35 30 25 20

CFͲCPB

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PFͲCPB OPCAB

10 5 0 Ͳ5

PreͲCPB

PostͲCPB

24hpostͲCPB

Conclusions. We observed a direct effect of CPB on endothelial function, which was greater in CF-CPB than in PFCPB. OPCAB seemed to preserve FMD. Reference. 1. Coretti MC, Anderson TJ, Benjamin EJ, et al. Guidelines for the ultrasonic assessment of endothelial-dependent flowmediated vasodilation of the brachial artery: a report of the International Brachial Artery Reactivity Task Force. J Am Coll Cardiol 2002; 26: 663-669.

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O-08 Administration of volatile anaesthetics during CPB: do we st need a 21 Century solution? 1

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R Isaac , J Campbell , A Pai , R Basu 1

Dept of Anaesthesia and Perfusion, Nottingham University 2 Hospitals, Nottingham, United Kingdom, Dept of Anaesthesia, Essex Cardiothoracic centre, Basildon, United Kingdom Introduction. Administration of volatile anaesthetic agents via an anaesthesia vaporiser mounted on the cardiopulmonary bypass (CPB) machine, although unlicensed, is widely practised in the United Kingdom (UK). We aimed to examine current practice. Method. An online questionnaire was sent to cardiac anaesthetists and chief perfusionists in the UK. Information collected included: type of volatile agent used, rationale for use, prevalence of gas monitoring and scavenging on CPB and usage of depth of anaesthesia monitoring. Results. A total of 296 responses were received from 521 questionnaires sent out (response rate 57%). Of these, 68% used volatile anaesthetic agents on CPB. The majority (96%) used isoflurane, with the remaining using either sevoflurane or desflurane. Most respondents used volatile agents throughout CPB [before application of the aortic cross-clamp (AXC) 84%; with AXC 85%; after AXC release 84%]. Rationales for volatile agent use were to reduce awareness (80%), for myocardial protection (68%) and to control blood pressure (61%). Only 47% used gas analysers and 17% did not use any scavenging. A depth of anaesthesia monitoring device was used by only 30% of respondents. Discussion. This survey confirms that a large number of units in UK use volatile agents on CPB. However, many units do not use any scavenging with potential health consequences for theatre personnel. Also, gas analyser usage is low. Serious incidents have been reported resulting from incorrect connections of vaporizers on the CPB machine ranging from volatile agent spillage to vaporizers preventing oxygen from reaching the oxygenator [1]. Vaporizers designed and manufactured to be mounted on anaesthesia machines have been adapted by local medical physics and perfusion teams to be used “off label” on CPB machines. Is it time for cardiac anaesthetists, in association with industry, perfusion and physics departments to standardize the administration of volatile agents during CPB? Reference. 1. MDA 2008/005, Medical device alert, 11 February 2008. www.mhra.gov.uk/Safetyinformation/Safetywarningsalertsand recalls/index.htm O-09 Cardioprotective effects of erythropoietin during cardiac surgery with cardiopulmonary bypass Marie Joyeux-Faure1, Michel Durand2, Damien Bedague2, 2 2 2 Marine Rossi , Vincent Bach , Olivier Chavanon , Pierre 2 Albaladejo 1

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Grenoble 1 University, Grenoble, France, University Hospital, Grenoble, France Introduction. Myocardial injury during cardiac surgery is associated with increased risk of early and late death after CABG under CPB [1]. Clinical and experimental studies suggest that recombinant human erythropoietin (EPO) independent of its erythropoietic effect, may be used as a cytoprotective agent against cardiac ischaemic injury [2]. We tested the hypothesis

that one large dose of EPO administered shortly before CPB limits the systemic elevation of cardiac biomarkers. Method. After ethics committee approval and written informed consent, 50 patients scheduled for CABG with CPB were -1 randomly allocated to receive EPO (epoietin beta, 800 UI kg iv., EPO group) or saline (control group) at the induction of anaesthesia. The primary end-point was the postoperative level of troponin T. Statistical analysis was performed using t test and Anova for repeated measures. Results. Preoperative data and perioperative management were similar in the 2 groups. Postoperative peak values of troponin T were not different between groups, reaching 0.59 ± -1 -1 0.54 μg L vs. 0.41 ± 0.45 μg L for EPO and control group respectively (P=0.21). The area under curve of troponin T was -1 -1 similar, 15.3 ± 8.0 h μg L for EPO group and 11.8 ± 6.6 h μg L for control group (P=0.11). No difference in the results of CK-MB or NT-ProBNP was found. Conclusion. One large dose of EPO given shortly before CPB, did not protect against postoperative myocardial injury. These findings do not support the use of EPO at this dose as a cytoprotective agent in patients undergoing CABG. References. 1. Fellahi JL, Gué X, Richomme X, et al. Short- and long-term prognostic value of postoperative cardiac troponin I concentration in patients undergoing coronary artery bypass grafting. Anesthesiology 2003; 99: 270-274. 2. Joyeux-Faure M, Godin-Ribuot D, Ribuot C. Erythropoietin and myocardial protection: what's new? Fundam Clin Pharmacol, 2005; 19: 439-446. O-10 BIS controlled isoflurane anaesthesia using CLADS versus manually controlled administration in open heart surgery Goverdhan Puri, Sethu Madhavan, Preethy M Joseph Post Graduate Institute of Medical Education and Research, Chandigarh, India Introduction. Literature relating to the administration of inhalational anaesthetics using closed loop systems is scarce. In this study, we compared the inhalational version of CLADS (a locally developed closed loop anaesthesia delivery system [1]) for administration of isoflurane (IAADS) with manual vapourizer control in elective open heart surgery. Method. Forty patients (ASA II-IV; 18-65 years) undergoing elective cardiac surgery requiring CPB were randomly divided into manual or closed loop (ISOCLADS) groups with the aim of controlling BIS to a target of 50. In the manual group, following propofol induction, isoflurane was administered through the Tech 7 vapourizer during pre and post CPB periods. In the closed loop group, it was administered through the IAADS system, using an infusion of liquid isoflurane into the expiratory limb of the closed circuit. Both groups were maintained on 500 mL 100% O2 FGF. The % of time BIS was within the set target (50 ± 10), MDPE. MDAPE, wobble, divergence [2], amount of isoflurane used, haemodynamic parameters, fentanyl and intraop. vasoactive drugs used were compared. Results. The demographic parameters, duration of surgery, pre CPB and post CPB times, CPB and cross-clamp times were similar in both groups. The IAADS maintained BIS near the target for a longer duration of time than manual control (Table). The BIS and haemodynamic responses to skin incision and sternotomy were also less in the ISOCLADS group. The amount of isoflurane used was lower in ISOCLADS group (10.2 ±4.4 mL vs. 10.61±2.3 mL).

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Table 1. Creatinine clearance values in Groups I, II and III PERFORMANCE % time BIS within ±10 of target MDPE MDAPE WOBBLE DIVERGENCE

IAADS (mean ±sd)

Manual (mean ±sd)

82±9

72±18

6±4 11±3 9.4±2 0.26±0.1

10±7 14±5 10±3 0.29±0.1

MDPE, median performance error; MDAPE, median absolute performance error

Conclusion. The study proves the feasibility and efficacy of closed loop control of anaesthesia in cardiac surgery compared to manual control using inhalational anaesthetics. References. 1. Puri GD, Kumar B, Aveek J. Closed-lop anaesthesia delivery system (CLADS) using bispectral index: a performance assessment study. Anaesth Intensive Care 2007; 35: 357-362. 2. Varvel JR, Donoho DL, Shafir SL. Measuring the predictive performance of computer-controlled infusion pumps. J Pharmacokinet Biopharm 1992; 20: 63-94.

GROUP I T1 107.06±30.5 T2 110.00±30.4 T3 110.83±23.5 T4 106.37±20.11 T5 105.67±24.32 T6 93.26±22.83* T7 93.72±27.92* *P<0.05 compared to T1 in same group

Renal functıonal effects of usıng N-acetyl-cysteıne ın cardıac surgery Banu Ayhan, Gülsün Pamuk, Basak Kantar, Meral Kantar, Bilge Çelebioglu, Ulku Aypar Hacettepe University, Ankara, Turkey Introduction. The aim of this study was to evaluate the effects of two different methods of using N-Acetyl-Cysteine (NAC) during coronary surgery on renal function. Method. Following ethical committee approval, 60 patients aged 18 to 75 with normal renal function before planned coronary artery bypass surgery were included in the study. The patients were randomly allocated to three groups: Group I had 50 mg/kg NAC added to their pump priming solution; Group II received 50 mg/kg NAC iv. right after induction and had an infusion of 20 mg kg-1 h-1 throughout the operation; Group III was the control group. Demographic and perioperative data, as well as fluid balance, urine output and drainage amounts at the end of operation, and at 24th and 48th postoperative hours were recorded. Haemodynamic data, BUN, creatinine, blood and urine electrolytes, and beta-2 globulin were measured, and creatinine clearance and fractional sodium excretion (FeNa) were deduced before induction (T1), before CPB (T2), after 30 minutes of CPB (T3), after CPB (T4), at the end of operation (T5), at postoperative 24 h (T6), and at postoperative 48 h (T7). Results. The groups had identical distribution in terms of demographic properties and clinical findings. There were no differences between the total amount of fluids given, urine outputs and drainage. Although BUN levels decreased, no difference between groups was found. Urinary albumin/creatinine ratios increased in Group I and Group III after T3 (P<0.05), whereas in Group II there was a statistically insignificant decrease. All creatinine values in all groups showed a statistically significant increase postoperatively (T6-T7 P<0.05). Beta-2 globulin increased in the control group starting at T5, whereas in Group I and II this increase started at 48 h.

GROUP III 101.51±30.34 100.81±27.27 100.31±26.58 94.37±24.07* 95.23±23.7* 87.26±30.56* 90.11±33.37*

Conclusion. Two different regiments of N-acetyl-cysteine in coronary artery bypass grafting have some beneficial effects, but fail to prevent late (24-48 h) damage. Further studies are needed to reach more definitive results. O-12 Adjustment of inspired oxygen fraction according to body surface area during cardiopulmonary bypass 1

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GROUP II 88.95±25.33 88.99±26.84 90.74±26.30 85.79±20.26 87.56±23.39 77.80±26.72* 78.68±29.03*

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Fevzi Toraman , Sahin Senay , Serpil Ustalar Ozgen , Behic 3 3 2 2 Danisan , Ebuzer Aydin , Hasan Karabulut , Cem Alhan 1

Acibadem University School of Medicine Department of 2 Anesthesiology and Reanimation, Istanbul, Turkey, Acibadem University School of Medicine Department of Cardiovascular 3 Surgery, Istanbul, Turkey, Acibadem Kadikoy Hospital Department of Cardiovascular Surgery, Istanbul, Turkey Introduction. This study aimed to investigate the safety of adjusting the inspired oxygen fraction according to body surface area during cardiopulmonary bypass. Method. Thirty patients scheduled for elective coronary bypass surgery under cardiopulmonary bypass (CPB) were enrolled in 2 groups. In group 1 the inspired oxygen fraction (FiO2) during cardiopulmonary bypass was adjusted to 0.35 during the hypothermic period, and 0.45 during the rewarming period. In group 2 it was adjusted according to the body surface area (BSA) and was calculated as (FiO2) = (0.21) x (BSA) during the hypothermic period and (FiO2) = (0.21 x BSA) + (0.10) during the rewarming period. PaO2 (mmHg), PaCO2 (mmHg), SaO2, (%) serum lactate levels, cardiopulmonary pump flow and mean arterial pressure measurements were recorded at 5 different th time intervals: T1. before the implementation of CPB, T2. 10 th minute of aortic cross-clamp (CC) period, T3. 20 minute of CC period, T4. after declamping, T5. before the termination of CPB. Results. Mean PaO2 levels were higher in Group 1, but there was no statistical difference between groups (Table 1). Lowest PaO2 levels in the same intervals in Group 1 vs. Group 2 were determined as; T1: 88 vs. 112, T2: 71 vs. 114, T3: 78 vs. 102, T4: 62 vs. 114,T5: 62 vs. 76 (P<0.01). Highest PaO2 levels in the same intervals in Group 1 vs. Group 2 were determined as; T1: 296 vs. 277, T2: 267 vs. 263 ,T3: 267 vs. 229, T4: 267 vs. 229,T5: 277 vs. 215 (P<0.01) There were more patients with hypoxaemia or hyperoxaemia in Group 1. Table 1. Mean, lowest and highest PaO2 levels (mmHg) in different time intervals.

T1 T2 T3 T4 T5

Mean Group 1

PaO2 Group 2

196±53 187±37 177±35 157±32 130±32

195±45 161±49 167±45 166±47 164±49

Lowest PaO2 Group 1 Group 2 88 71 78 62 62

112 114 102 62 76

Highest PaO2 Group 1 Group 2 296 267 267 267 277

277 263 229 229 215

*P<0.01 (intergroup comparison)

Conclusions. Adjustment of inspired oxygen fraction according to body surface area during cardiopulmonary bypass may provide a safer range of PaO2 in coronary surgery.

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O-13 Red blood cell use in elective cardiac and vascular surgery: prospective assessment of the effect of a transfusion guideline in a University Hospital 1

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Reto Basciani , Stefano Fontana , Behrouz Mansuri Taleghani , 3 3 1 1 Urs Müller , M Perler , L Krummen , A Läderach , Balthasar 1 Eberle 1

University Hospital Bern, Inselspital, Bern, Switzerland, Regional Blood Donation Service of the Swiss Red Cross, 3 Bern, Switzerland, Institute for Evaluative Research in Orthopaedic Surgery, University of Bern, Bern, Switzerland 2

Introduction. Limited data and no general guidelines on transfusion practice in elective cardiac and vascular surgery are available in Switzer-land. We started a single centre study, analysing our pre-intervention transfusion practice and the effects after the introduction of a simple guideline on red blood cell transfusion (RBC). Method. Prospective, before-and-after study comparing the use of RBC in major adult cardiac and vascular surgery (valve replacement, coronary bypass, open abdominal aortic aneurysm procedures) before and after the implementation of a transfusion guideline. RBC use and patient outcomes were monitored for 6

months. During this phase, aprotinin was withdrawn from the market and substituted by tranexamic acid. Thereafter, an institutional RBC guideline was introduced, implemented, with data monitoring continuing for another 6 months. Results. Preliminary data of 797 patients (414 before and 383 after; 91.3% cardiac, and 8.7% vascular surgery, median ASA physical status 3, median EuroSCORE 5) were available. Median hospital length of stay was 8 days before and after the guideline implementation; median follow up before and after was 39 and 42 days, respectively. Main results are summarized in the table. Proportion of transfused patients Number of transfused RBC units Hb before first transfusion (g/L) In-hospital mortality In-hospital morbidity Follow up mortality Follow up morbidity

Before 67.9 2.5 80.1 ± 10.9 1.2 15.2 1.2 19.1

After 75.7 3.0 75.2 ± 7.5 2.1 12.5 2.6 17.5

P 0.015 n.s. <0.001 n.s. n.s. n.s. n.s.

Conclusions. The introduction of a RBC transfusion guideline modified the transfusion behaviour by lowering the haemoglobin transfusion trigger. Nevertheless, the proportion of transfused patients as well as the number of transfused RBC`s increased. The change in antifibrinolytic prophylaxis may explain part of this unexpected result.

Oral Session III – Echocardiography O-14 Low frame rate in RT 3 D zoom mode has little influence in predicting annuloplasty ring size during mitral valve repair Jörg Ender, Sarah Eibel, Heinz Tschernich, Diana Mathioudakis, Dirk Haentschel, Chirojit Mukherjee Heartcenter Leipzig, University Leipzig, Leipzig, Germany Introduction. With real time 3 D transoesophageal echocardiography two different modes for visualizing the whole mitral valve are available. In 3 D zoom the mitral valve can be visualized within one heart beat but with low frame rate and in full volume mode within 4 heart beats but with higher frame rate. The aim of the study was to compare the two modes while using a software which allows superimposing computer aided design models of annuloplasty rings to 3 D TOE loops to predict the correct ring size in mitral valve repair. Method. In patients undergoing elective mitral valve repair a RT 3 D examination (IE 33 Philips, Netherlands) of the mitral valve was performed pre- and postoperatively using the 3 D zoom and the full volume mode. The digitally stored loops were imported in a modified version of the 4 D valve assessment® software called ring tool (TomTec, Germany) with the possibility of superimposing CAD models of Carpentier Edwards Physio® annuloplasty rings. The actually implanted ring size by the surgeon was compared with the annuloplasty ring size predicted by ring tool. The echocardiographer using ring tool was blinded for the surgical result. Results. Twenty patients were included in the study. Frame rate of 3D zoom mode loops were 8 Hz and frame rate of full volume 22 Hz. The correlation of the predicted ring size by ring tool and the actual implanted ring size was 0.92 for 3 D zoom mode and 0.91 for full volume mode preoperatively and 0.95 vs. 0.96 postoperatively. For differences in predicted and implanted ring size see table. Conclusion. For predicting annuloplasty ring size with ring tool 3 D zoom is as good as full volume acquisition. Because 3 D zoom is the real time mode and insensitive to ecg and

ventilatory artefacts it may be the preferred mode for this application. Table. Differences between zoom and full volume mode in ring sizes. N=20 (%) Diff. in sizes 0 11+

ring

Zoom pre OP 15 (75) 2 (10) 3 (15)

Zoom post Op 16 (80) 3 (15) 1 (5)

Full pre Op 15 (75) 1(5) 4 (20)

Full post OP 18 (90) 2 (10) 0 (0)

O-15 Height of the anterior mitral leaflet is a better predictor for the annuloplasty-ring size than the intercommissural distance in patients undergoing mitral valve repair Jörg Ender, Sarah Eibel, Diana Mathioudakis, Heinz Tschernich, Dirk Haentschel, Chirojit Mukherjee Heartcenter, University Leipzig, Leipzig, Germany Introduction. Surgical mitral valve (MV) repair is performed routinely with implantation of an annuloplasty ring. Usually the sizing is performed by the surgeon with a commercial sizer. The correct sizer covers the intercommissural distance of the native valve as well as the height of the anterior leaflet. The aim of this study was to investigate if measurement of the intercommissural distance based on an RT 3D TOE examination correlates better with the actual implanted annuloplasty-ring size than the measurement of the height of the anterior mitral leaflet. Method. Fifty three patients were included in this study after approval of the local ethic committee and written informed consent. An RT 3 D TOE examination (IE 33 Philips, Netherlands) of the mitral valve was performed preoperatively in patients undergoing elective MV repair. These loops were imported in the 4 D valve assessment® software (TomTec, Germany). Then the intercommissural distance of the mitral valve was measured and the ring size predicted using the inner intercommissural diameter of the Physio® Edward annuloplastyring as stated by the manufacturer. Additionally the height of the

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anterior mitral leaflet was measured and the ring size predicted using the anterior-posterior diameter of the Physio® Edward annuloplasty-ring. The actual implanted ring size by the surgeon using conventional sizing was compared with the annuloplasty ring size predicted with both echocardiographic measurements. The surgeon was blinded for the echocardiographic measurements. Results. The correlation between the predicted annuloplasty ring size using the intercommissural distance and the actual implanted ring size was 0.55. The correlation of the implanted annuloplasty ring size and the preoperative measurement of the height of the anterior mitral leaflet was 0.75. Conclusion. Measurement of the height of the anterior mitral leaflet correlates better than the measurement of the intercommissural diameter with the actual implanted annuloplasty-ring size. O-16 Use of intraoperative transoesophageal echocardiography in adult cardiac surgery: a European perspective Giuseppe D'Ancona1, Fabio Guarracino2, Matteo Parrinello1, 1 1 Antonio Arcadipane , Michele Pilato 1

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ISMETT, Palermo, Italy, Ospedale Cisanello, Pisa, Italy

Introduction. At present there is no information concerning routine application, according or not to guidelines, of intraoperative trans-oesophageal echocardiography (TOE) in cardiac surgery. Method. A survey was sent to 50 randomly selected European cardiac surgery centres to investigate intraoperative routine use of TOE. Results. Thirty-two centres (64%) returned the questionnaire. Although most respondents (25/32; 78%) think TOE is a necessary intraoperative quality control tool, the majority of centres do not use it routinely during standard cardiac surgery (20/32; 62%) or valve surgery (20/32; 62%). Even after reparative valve surgery or in patients with depressed ventricular function, a considerabe number of centres do not adopt TOE (15/32; 47% and 16/32; 50% respectively). The majority of respondents (22/32; 68%) did not identify a specific reason for not performing intraoperative TOE. We divided the respondents into TOE routine users (RU; 12) and non-routine users (NRU; 20). TOE is used many more times yearly in the RU group (RU 1100±737 vs. NRU 273±237; P=0.003) and by dedicated TOE board certified anaesthesiologists (RU 10/12 vs. NRU 7/20; P=0.008). Cardiologist consultation for complicated cases was requested equally in the two groups (RU 8/12 vs. NRU 13/20; P=ns). Conclusions. In spite of its recognized potential and for reasons other than human or material resources, intraoperative TOE is not routinely used in cardiac surgery. Routine TOE is often supported by dedicated anaesthesiologists with TOE board certification. Lack of routine experience with intraoperative TOE interpretation is not supported by routine cardiology consultation. This could potentially lead to misdiagnosis of actual clinical status.

O-17 Evaluation of the coaptation length and coaptation length index after mitral valve repair and correlation with the degree of residual mitral regurgitation Paula Carmona, José Luis Soriano, Ignacio Marqués, Sergio Cánovas, José De Andrés, Rafael G. Fuster, Juán M. León Consorcio Hospital General Valencia, Valencia, Spain Introduction. Mitral valve (MV) reconstruction has become the treatment of choice for mitral insufficiency. Intraoperative echocardiographic information about the valve morphology after repair is limited. The aim of the study was to evaluate intraoperative echocardiographic measurements, coaptation length (CL) and coaptation length index (CLI) after mitral valve repair and its correlation with the degree of residual mitral regurgitation (MR). Method. All consecutives mitral valve repairs performed in patients with moderate or severe MR were included. Carpentier’s classification was used to classified mitral valve insufficiency. Transoesophageal echocardiography views for measurements were four chamber, two chamber, long axis views and transgastric fish mouth view. We measured mitral valve short axis dimension (MVd) at end systole, the whole length of the anterior leaflet during diastolic phase (Ad) and the length of uncoapted-free portion of the anterior leaflet at endsystole (Ac). CL was defined as: Ad-Ac and CLI as: Ad-Ac/MVd. Statistical analysis used Student´s t-test for paired data and Spearman’s rank correlation. Results. To abstract date 19 patients were enrolled in the study. One was excluded due to poor quality images. Preoperative MR classification was type I in 3, type II in 12 and type III in 3 patients. Mitral valve repair alone was performed in 12 cases, with associated CABG in 3 and associated surgery on a different valve in 3. Residual MR using a scale from 0 to 4 was 0/4 in 10 patients, 1/4 in 7 and 2/4 in 1. CL and CLI increased significantly intraoperatively after repair (P<0.05). There were differences in the CL between the patients with residual MR. (No statistically significant correlation). Table 1. CL/CLI 4 ch (mm) CL/CLI 2 ch (mm) CL/CLI Long axis (mm) *P<0.05

Pre-repair

Post-repair

3.0(2.4)*/ 0.1(0.06)* 2.5(2.1)* 0.1(0.05)*

9.4(2.9)*/ 0.2(0.1)* 7.1(2.4)*/ 0.2(0.05)*

Residual MR 0/4 10.1(2.00)/ 0.2(0.07) 7.3(2.03)/ 0.2 (0.04)

Residual MR 1/4 7.9(3.2)/ 0.2 (0.1) 6.1(2.7)/ 0.2 (0.06)

4.6(3.6)*/ 0.12(0.1)*

8.8(2.5)*/ 0.2(0.06)*

8.71(2.43)/ 0.2(0.04)

8.7(3.4)/ 0.2(0.09)

Conclusion. To abstract date, the sample size was small and therefore there was no statistically significant correlation between post-repair CL or CLI and the degree of residual MR. We could appreciate however, detectable echocardiographic differences between groups.

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O-18 Cost-effectiveness analysis of modified transoesophageal echocardiography to assess the distal ascending aorta before incision in cardiac surgery patients 1

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Arno Nierich , Bas van Zaane , Hendrik Koffijberg , Karel 3 Moons 1

Department of Anaesthesia and Intensive Care, Isala Clinics, 2 Zwolle, Netherlands, Division of Perioperative Care and Emergency Medicine, University Medical Centre, Utrecht, 3 Netherlands, Julius Centre for Health Sciences and Primary Care, University Medical Centre, Utrecht, Netherlands Introduction. Post-operative stroke in on-pump cardiac surgery is often caused by emboli from the atherosclerotic ascending aorta after manipulation. Knowing the presence and extent of atherosclerosis prior to sternotomy allows changes in surgical strategy to reduce or avoid manipulation of the ascending aorta. We assessed the cost-effectiveness of applying modified transoesophageal echocardiography instead of manual palpation for the detection of atherosclerosis in the ascending aorta. Method. A Markov decision-analytical model was developed and used to assess differences in costs and health effects between the two strategies. The incremental cost-effectiveness ratio was calculated for subgroups of patients, aged 55, 65 and 75 years, and separately for men and women. Conservative as well as observed prevalence rates of atherosclerosis were defined per age category. Probabilistic sensitivity analysis was used to determine the robustness of the results. Results. The A-View strategy consistently resulted in more adapted procedures and, consequently, in a lower risk of stroke and a slightly higher number of life-years. The incremental costs for the A-View decreased with patient age whereas incremental effects increased with patient age. The incremental costseffectiveness ratio (ICER) ranged from €4,937/QALY for 55year-old men to €-6,191/QALY for 75-year-old women. Conclusions. The A-View strategy in cardiac surgery is highly likely to reduce costs and increase health benefits in patients older than 65 years. In subgroups of patients in which the AView strategy is more expensive than the manual palpation strategy, the additional costs will likely be small compared with the additional health benefits. Cost-effectiveness will still be acceptable. O-19 Transapical aortic valve implantation guided and assessed by transoesophageal echocardiography Marian Kukucka1, Axel Unbehaun2, Alexander Mladenow1, 2 1 Miralem Pasic , Hermann Kuppe 1

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Institute of Anesthesiology, Institute of Cardiothoracic Surgery, German Heart Institute Berlin, Berlin, Germany Introduction. Transapical aortic valve implantation is monitored by continuous fluoroscopic imaging. We performed simultaneously TOE monitoring of the procedure and assessed the possibility of TOE being used as the sole imaging guide for the procedure. Method. We studied 161 patients (age 78.9r9.0 years) .The mean logistic EuroSCORE for the whole group was 38.3 r 19.7%. The procedural steps were assessed by TOE: 1) positioning of the venous wire in the RA, 2) pigtail catheter positioning in the ascending aorta, 3) apex puncture and passing the wire through the aortic valve, 4) insertion of the 14-

Fr sheath, 5) placement of a stiff guide wire and positioning it in the descending aorta, 6) balloon valvuloplasty of the native aortic valve, 7) introduction of the 26-Fr delivery system 8) valve deployment, 9) recovery of global heart function, 10) assessment of the valve function), 10) coronary flow, 11) exclusion of new regional wall motion abnormalities, and 12) precise diagnosis of aortic regurgitation with Doppler and contrast echocardiography. Results. The procedure could be guided and monitored by TOE in 10 of 12 steps. Fluoroscopy was always indispensable for valve deployment. Ejection fraction improved immediately postprocedure (52r12 vs. 63r16, P=0.0001). Relative improvement in EF in the group with pre-procedural severe reduced EF (<35%) was more pronounced compared to the patients with EF t35% pre-procedure (P=0.000001). The 30 day mortality in this group was 5%. The mean transvalvular gradient (23 mm valves) was 6.4r2.4 mmHg and for the 26 mm valves 6.2r3.35 mmHg (P=0.76). The mean aortic valve area in the patients receiving 23 mm valve was 1.69r0.49 cm2 and in patients received 26 2 mm valve was 2.05r0.47 cm (P=0.001). Conclusions. TOE-guided valve implantation was possible in 10 of 12 procedural steps. TOE was necessary for monitoring and assessment of the procedure. O-20 Impact of age, left ventricular ejection fraction and gender on the left ventricular end-diastolic area in patients undergoing elective CABG Giovanna Lurati-Buse, Corsin Poltera, Miodrag Filipovic, Daniel Bolliger, Manfred Seeberger University Hospital of Basel, Basel, Switzerland Introduction. The objective of our investigation was to consider the impact of patient-related factors on the indexed left ventricular end-diastolic area (LVEDAI) measured by transoesophageal echocardiography (TOE) after anaesthesia induction, in patients undergoing elective coronary artery bypass graft (CABG) surgery. Method. Studies reporting on LVEDAI after induction of anaesthesia for CABG surgery were identified by electronic search of the MEDLINE database until 2006 and by manual search of 5 anaesthesiology and cardiology journals from 1990 to 2006. After selection according to predefined criteria, we contacted the authors of the included papers for raw data of the individual patients to generate a new study population. Patients' pooling was conducted only after we had visually checked the LVEDAI values of the different studies for inhomogeneity. We then calculated the impact of age, gender and left ventricular ejection fraction (EF) on LVEDAI by uni- and multivariate linear regression in the new study population. Results. Nine of the 638 papers identified by the electronic search and 3 studies identified by manual search reported LVEDAI after induction of anaesthesia in elective CABG patients. We obtained raw data for the generation of a new study population from the authors of 6 studies. Thus, the study population consisted in 223 patients, 184 men (83%), aged 64±10 years (mean ±standard deviation) and with an EF 61±16%. The LVEDAI was 9.3±3.0. The univariate analysis showed weak significant correlation between LVEDAI and both age and EF but not with gender. After multivariate correction, the ȕ values were 0.051 (95% confidence interval [CI] 0.01 to 0.092, P=0.015) for age and -0.059 (95% CI -0.082 to -0.037, P<0.001) for EF. Conclusion. The LVEDAI measured by TOE after anaesthesia induction is significantly but very weakly correlated with age and preoperative EF in patients undergoing elective CABG.

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O-21 Do anaesthesia and positive pressure ventilation have an impact on left ventricular end-diastolic dimensions measured by echocardiography? Giovanna Lurati-Buse, Corsin Poltera, Miodrag Filipovic, Daniel Bolliger, Manfred Seeberger University Hospital of Basel, Basel, Switzerland Introduction. The aim of our investigation was to consider the impact of anaesthesia and positive pressure ventilation (PPV) on left ventricular (LV) end-diastolic (ED) area (EDA) after anaesthesia induction in patients undergoing coronary artery bypass graft (CABG) surgery. Method. Studies reporting LV EDA after induction of anaesthesia for coronary artery bypass surgery were identified by electronic search of the MEDLINE database until 2006 and by manual search of 5 anaesthesiology and cardiology journals from 1990 to 2006. After selection according to predefined criteria, we contacted the authors of the included papers for raw data of the individual patients to generate a new study population. Patients' pooling was conducted only after we had

visually checked the LV EDA values of the different studies for inhomogeneity. These data were compared to published reference values obtained in awake, spontaneously breathing patients with CAD. Results. The searches identified 12 suitable papers. We obtained raw data for the generation of a new study population of anaesthetized patients from the authors of 6 studies. We found one transthoracic echocardiographic study reporting LV ED dimensions in spontaneously breathing CAD patients. It included only patients with an ejection fraction >45% and it reported LV ED diameters (LV EDD) only. We thus restricted comparison to CABG patients fulfilling the same criteria and approximated LV EDD in the new CABG study population of 199 patients by 2¥ LVEDA/ʌ. Mean±SD of LVEDD was 4.5±0.6 in the CABG patients and 5.1±0.5 in the awake CAD patients. As we could not obtain raw data of the CAD patients, we did not perform significance testing. Conclusion. Studies on the impact of anaesthesia and positive pressure ventilation on LV end-diastolic dimensions are sparse. Based on our study, we can only speculate that normal values in anaesthetized CAD patients might not differ from those found in awake patients. Studies are needed to determine normal values of LV EDA / EDD in anaesthetized and mechanically ventilated patients with CAD.

Oral Session IV – Glucose Management O-22 Tight glucose control after cardiac surgery: temporal blood glucose analysis reveals the risks of iatrogenic hypoglycaemia 1

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Giuseppe D'Ancona , Lucia Sacchi , Federico Bertuzzi , 2 1 1 Riccardo Bellazzi , Antonio Arcadipane , Gianluca Santise , 1 1 1 Sergio Sciacca , Marco Turrisi , Michele Pilato 1

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ISMETT, Palermo, Italy, University of Pavia, Pavia, Italy, 3 Ospedale Niguarda, Milano, Italy Introduction. The clinical effects of tight glucose control in cardiac surgery patients should be evaluated using temporal blood glucose parameters that summarize glycaemia fluctuations and trends during hospitalization. Method. A protocol including insulin drip and 5% dextrose infusion was adopted to achieve target ICU glucose levels between 4.4-6.9 mmol/L in a consecutive series of adult cardiac surgery candidates. Hourly ICU glucose levels were prospectively recorded. Glycaemia standard deviation, percentage of time spent with glycaemia >6.9 mmol/L, area under the curve (AUC) for glycaemia >6.9 mmol/L, lability index, presence and number of hypoglycaemic (<3.85 mmol/L) episodes were recorded and analysed together with demographic, major comorbidity, and surgical data. Determinants for M/M were chased by means of multivariate analysis. Results. Data from 596 patients were analysed. There was a univariate correlation between mortality and glucose standard deviation, liability index, and hypoglycaemia occurrence. At multivariate analysis none of the temporal blood glucose analysis data seemed to impact upon hospital mortality apart for occurrence of hypoglycaemia (P=0.02; OR=9) that was second only to obesity (P=0.008; OR=13) followed by liver dysfunction (P=0.02; OR=8). Glycaemia data were not independently correlated to any of the recorded major morbidities. To clarify the determinants of hypoglycaemia, a second multivariate model was built. Diabetes (P=0.0001; OR= 23) and chronic renal failure (P=0.01; OR=25) were the sole determinants for hypoglycaemia. Conclusion. A timely temporal analysis of blood glucose levels after heart surgery has revealed that iatrogenic hypoglycaemia secondary to tight glucose control results in higher perioperative

mortality risks. On the contrary, failure to maintain glycaemia <6.9 mmol/L through time does not impact on mortality and morbidity. Particular caution in glycaemia monitoring and higher glycaemia targets should be advised in the perioperative management of patients with diabetes and renal failure as both conditions independently increase the risk of hypoglycaemia occurrence. O-23 Tight glucose control after cardiac surgery: iatrogenic hypoglycaemia is an independent predictor for renal failure and perioperative mortality Giuseppe D'Ancona1, Federico Bertuzzi2, Francesco Pirone1, 1 1 1 Vincenzo Stringi , Gianluca Santise , Sergio Sciacca , Antonio 1 1 1 1 Arcadipane , Michele Pilato , Marco Turrisi , Domenico Biondo 1

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ISMETT, Palermo, Italy, Ospedale Niguarda, Milano, Italy

Introduction. Recent evidence suggests that iatrogenic hypoglycaemia resulting from tight glucose control may increase ICU morbidity and mortality (M/M). The aim of this study was to test this hypothesis in a cohort of cardiac surgery patients. Method. A protocol including insulin drip and 5% dextrose infusion was adopted to achieve target ICU glucose levels between 4.4-6.9 mmol/L in 655 consecutive cardiac surgery patients. Hourly ICU glucose levels were prospectively recorded. The analysis focused on the impact on morbidity and mortality of average glucose level, glucose standard deviation and glucose minimum and maximum levels during ICU stay. Results. Median age was 67 yr. 126 (19.2%) patients had diabetes, 68 (10.4%) depressed LVEF, 30 (4.6%) impaired renal function, and 7 (1.1%) were on dialysis. MV surgery was performed in 297 (45%) patients, AV surgery in 319 (48%), TV surgery in 9 (1.4%), aortic surgery in 30 (4.5%), combined valve procedures in 34 (5.2%), and associated CABG in 148 (22.6%). Mean ICU glucose level was 7.0±0.66 mmol/L, mean ICU glucose standard deviation was 1.44±0.66 mmol/L, and in 100 (15%) patients at least one episode of hypoglycaemia (<3.56 mmol/L) occurred. At multivariate analysis, patient ICU glucose average level, maximum glucose level, and glucose standard deviation were

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not independently correlated to M/M data. Glucose ICU minimum level was inversely correlated to mortality (P=0.03; OR=0.9), perioperative renal impairment (P=0.03; OR=0.9), and requirement for post-operative dialysis (P=0.01; OR=0.9) (the lower the glucose level the higher the mortality/renal impairment/dialysis risk). Receiver operating characteristic plots clearly showed maximal specificity and sensitivity for ICU glucose cut-offs values of 3.7 mmol/L (for mortality), 4.2 mmol/L (for dialysis), and 4.4 mmol/L (for renal impairment). Conclusion. In our experience, tight glucose control in patients undergoing routine heart surgery should be reconsidered and target glucose levels should be re-discussed. In particular, the risks of hypoglycaemia may offset the benefits of tight normoglycaemia and increase mortality rate and specific morbidities such as renal failure. O-24 Audit of the effect of long term glucose control on length of stay in cardiac surgery patients Thomas Varughese, Palanikumar Saravanan, Andrew Knowles Lancashire Cardiac Centre, Victoria Hospital, Blackpool, United Kingdom Introduction. Preoperative HbA1c level is predictive of adverse events after cardiac surgery and is associated with reduced longterm survival [1]. We undertook a prospective survey to find out whether HbA1c levels correlated with hospital stay and mortality after cardiac surgery in our practice. Method. We collected data prospectively on 100 diabetic patients presenting for cardiac surgery over a period of nine months from October 2007 to July 2008. Approval for the study was obtained from the Clinical Audit department. Venous blood obtained during the time of insertion of the central venous line was used for HbA1c testing. The outcomes compared were the ICU stay, postoperative stay, total length of stay in the hospital and mortality. Preoperative glucose control was considered to be excellent if HbA1c level was less than 7 and to be poor if the level was more than 9 according to our local guidelines. Results. Preoperative glucose control as measured by HbA1c was unsatisfactory in 52% of patients and poor in 10% of patients. There was no difference in ICU stay, postoperative stay and total length of hospital stay with different HbA1c levels (HbA1c<7, HbA1c 7-9, HbA1c >9) (Table 1). Patients with Type 1 diabetes had unsatisfactory glucose control and longer postoperative and hospital stay. Patients with diet controlled diabetes had longer hospital stay and 2 patients died. Table 1. Postoperative and total length of hospital stay (days). HbA1c <7 HbA1c 7 - 9 HbA1c >9 Diet Type 1 Type 2

Postoperative Stay Mean Median 9.3 6 11 7 7.8 7.5 8.8 7.0 18.4 7.0 8.6 7.0

Total Length of Stay Mean Median 16.5 8.5 19.4 10 14 10 17.9 11.5 33.7 12.5 14.0 9.0

Discussion. Our study is limited by the small number and further large studies will be required to determine the influence of the type of diabetes, treatment and the glucose control in outcome measures. References. 1 Halkos ME, Lattouf OM, Puskas JD, et al. Elevated preoperative hemoglobin A1c level is associated with reduced long term survival after coronary artery bypass surgery. Ann Thorac Surg 2008; 86: 1431-1437.

O-25 Analysis of cytokines secretion and clinical outcome in diabetic patients undergoing surgical myocardial revascularization Mario Bernardo1, Angelo Eramo1, Vincenzo Bernardo2, Riccardo 2 2 1 Barchetta , Mauro Falco , G. Emanuele Di Marzio , Alessandro 1 F. Sabato 1

Dep. of Anaesthesia & Intensive Care, University of Rome “Tor 2 Vergata”;, Rome, Italy, Dep. Cardiovascular Pathology, European Hospital, Rome, Italy Introduction. Diabetes mellitus is an important cardiovascular risk factor and a frequent co-morbidity in patients undergoing coronary artery bypass (CABG) [1]. We investigated the influence of cytokines network on clinical outcome and renal, hepatic and myocardial dysfunction in diabetic patients. Method. After local ethical approval, we enrolled 8 patients with diabetes mellitus type II (DM) and 8 patients without DM (Contr) undergoing CABG and extracorporeal circulation (ECC). Blood samples were collected to evaluate TNF-Į, p55R, IL-6, IL-8, IL1ȕ, IL-12, IL-10, IL-4, IL-6r, INFȖ, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), cardiac, renal and hepatic markers in both groups before anaesthesia (T0), after anaesthesia before ECC (T1), 6 h after ECC (T2), after 24 h (T3) and after 96 h (T4) from anaesthesia induction. We considered as clinical outcome: length of stay in the intensive care unit (ICU), hospitalization, renal, hepatic and myocardial function markers alterations. Data (mean ± SD) were analysed using t-test (P<0.05) and linear correlation (r >0.5). Results. DM patients showed increased CRP levels at T3 and T4 (P<0.05). At T0, IL-4 was lower in DM than control group (DM 0.15±0.23 pg/ml vs. Contr 0.64±0.43 pg/ml; P<0.05). ICU stay and hospitalization were longer in the DM group (ICU stay: 1.5 days vs. 1 day; hospitalization: 7.38 d vs. 4 d, P<0.05). Only for DM patients at T0, a correlation was present between TNF-Į and hospitalization (r = 0.76) and between p55R and ESR, CRP (r =0.75). Evaluating the whole population, at T0, IL-12 correlates with hospitalization (r = 0.65) and ICU stay (r = 0.63) whereas at T4, DM IL-12 is associated with augmented hepatic enzymes and TNF-Į with cardiac necrosis markers (r = 0.74). At T4, p55R values were associated with altered renal function, measured as >50% creatininaemia and blood urea baseline increase (DM: r = 0.73; Contr: r = 0.88). Conclusions. Despite this small population, these preliminary data showed in diabetic patients undergoing CABG, an important correlation between preoperative TNF-Į and IL-12 with hospitalized patients and a relationship between cytokines and organ function markers. References. 1. Carson JL, Scholz PM, Chen AY, et al. Diabetes mellitus increases short-term mortality and morbidity in patients undergoing coronary artery bypass surgery. J Am Coll Cardiol 2002; 40: 418-423. O-26 Haemoglobin-A1c as a predictor for infection post coronary bypass surgery Walid Abukhudair, Kamel Othman Ali, Abdulla Ashmeg King Fahad Armed Forces Hospitals, Jeddah, Saudi Arabia Introduction. The aim was to determine the prevalence of elevated haemoglobin-A1c (HbA1c) levels, a marker of glycaemic control, in patients presenting for coronary artery bypass surgery, to assess whether uncontrolled diabetes (high

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HbA1c) was a risk factor for infections and to consider if good preoperative glycaemic control (HbA1c levels <7%) was associated with decreased postoperative infections. Method. We carried out a retrospective observational study of our data base from January 2006 to December 2008, of 712 patients who underwent CABG ± valve surgery. Among them, 478 patients (67%) were diabetic and 234 (33%) were nondiabetic. Primary outcomes were infection complications, including pneumonia, wound infection, urinary tract infection, or sepsis. Bivariant analysis was used first to determine the association of each independent variable (age, race, diabetic, elective vs. emergent procedure and HbA1c levels) with outcome. Factors

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significant at P<05 were used in a multivariable logistic regression model. Results. In the multivariable model, age, operation length, infection types, emergency/urgent cases and HbA1c levels were significantly associated with postoperative infections. An HbA1c level of less than 7% was significantly associated with decreased infection complications with an adjusted odds ratio of 2.13 (95% confidence interval, 1.23-3.70); P=007. Conclusion. Good preoperative glycaemic control (HbA1c levels <7%) was associated with a decrease in infection complications post CABG.

Oral Session V – Haemostasis & Transfusion O-27

O-28

Effects of impaired primary haemostasis on postoperative bleeding in patients undergoing aortic valve replacement

Coagulation-fibrinolysis changes and TAFI activation during off-pump coronary artery bypass grafting: effect of two different heparin dosages

Daniel Bolliger, Manfred Seeberger, Salome Dell-Kuster, Michael Gregor, Patrick Meier, Urs Zenklusen, Esther Seeberger, Miodrag Filipovic University Hospital Basel, Basel, Switzerland Introduction. Acquired von Willebrand (vW) syndrome type IIA and alterations in platelet function may impair primary haemostasis in patients with severe aortic stenosis [1]. We hypothesized that patients undergoing aortic valve replacement who have impaired primary haemostasis will have increased postoperative bleeding. Method. With written informed consent we included 30 consecutive patients with severe aortic stenosis defined as 2 valve orifice area <1.0 cm in this preliminary analysis. We performed vW factor multimer analysis and measured plasma vW factor antigen and collagen binding capacity by ELISA. In addition, we performed platelet function analysis by impedance aggregometry. In all patients, postsurgical blood loss from mediastinal drainages was documented after 3, 6, 12 and 24 hours. Results. Mean age in the enrolled patients (15 male and 15 female) was 74 ± 9 years (range from 58 to 88). Loss of the largest multimers was present in 25 (81%) patients, decreased von Willebrand factor collagen-binding activity in 15 patients (50%), and global platelet function abnormality assessed by TRAP test in 9 (30%) patients. In all but one patient (97%), at least one of these disorders was present. Cumulative postsurgical blood loss was 120 ± 150 ml (mean ± SD) after 3 hours, 210 ± 215 ml after 6 hours, 300 ± 285 ml after 12 hours, and 425 ± 315 ml after 24 hours. Blood loss of more than 1000 ml after the first 24 hours was found in two patients (6%) with loss of the largest vW multimers but normal platelet function. No patient required re-exploration for massive bleeding. Conclusion. Although preoperative disorders of the primary haemostasis including acquired vW syndrome type IIA and impaired platelet function are common in patients with severe aortic stenosis, the postoperative bleeding volume was small and the incidence of postoperative massive bleeding low. These data suggest that reasons other than impaired primary haemostasis must be excluded in massive postoperative bleeding after aortic valve replacement. References. 1. Vincentelli A, Susan S, Le Tourmeau T, et al. Acquired von Willebrand syndrome in aortic stenosis. N Engl J Med 2003; 349: 343-349.

Domenico Paparella1, Giovanni Rubino2, Giuseppe Scrascia1, 2 1 Maria Arbues , Antonella Galeone , Luigi de Luca Tupputi 1 3 1 Schinosa , Nicola Semeraro , Mario Colucci 1

2

Division of Cardiac Surgery, Department of Anesthesia, Department of Biomedical Sciences, University of Bari, Bari, Italy 3

Introduction. To date, no study has tested the effect of different heparin dosages on the haemostatic changes during off-pump CABG (OPCAB), although a wide variety of empirical anticoagulation protocols are being applied. We tested the effect of two different heparin dosages on the activation of the haemostatic system in patients undergoing OPCAB procedures. Method. Forty-two patients eligible for OPCAB procedures were assigned in a randomized fashion to: Low Dose Heparin (150 IU/kg) or High Dose Heparin (300 IU/kg). Prothrombin fragment 1+2 (PF-1,2), plasmin/alpha2-plasmin inhibitor complex (PAP), D-dimer, soluble tissue factor (TF), tissue factor pathway inhibitor (TFP), total TAFI (thrombin activatable fibrinolysis inhibitor) and activated TAFI were assayed by specific ELISAs at 6 different timepoints, before, during and after surgery. Platelet function was evaluated by means of an in vitro bleeding time test (PFA-100). Results. OPCAB was accompanied by significant changes of all plasma biomarkers but soluble tissue factor, indicative of systemic activation of coagulation and fibrinolysis. All haemostatic changes were similar in the two heparin groups, even perioperatively, when the difference in anticoagulation was maximal (PF-1.2: P<0.001 within groups; P = 0.49 between groups. PAP: P<0.001 within groups; P = 0.65 between groups. TF: P<0.001 within groups; P = 0.40 between groups. TFPI: P<0.001 within groups; P = 0.21 between groups. TAFIa: P<0.001 within groups; P = 0.21 between groups. D-dimers: P<0.001 within groups; P = 0.55 between groups). Multiple regression analysis indicated that prothrombin F1+2 but not plasmin/alpha2-plasmin inhibitor complex was independently associated with TAFIa level. PFA-100 values did not change significantly after OPCAB. Conclusion. Both early and late haemostatic changes, including TAFI activation, are similarly affected in the low and high heparin groups, suggesting that the increase in heparin dosage is not accompanied by a better control of clotting activation during OPCAB.

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O-29 The effects of balanced solutions on blood coagulation: an in vitro study using thromboelastometry 1

1

2

Alexey Schramko , Ann-Christine Lindroos , Tomohisha Niiya , 1 1 Raili Suojaranta-Ylinen , Tomi Niemi 1

2

Helsinki University Hospital, Helsinki, Finland, Sapporo Medical University School of Medicine, Sapporo, Japan

Introduction. The slow degradable balanced hydroxyethyl starch (HES) solutions may disturb blood coagulation less than unbalanced HES. The aim of this study was to investigate in vitro effects of the totally balanced fluid concept on coagulation. We combined balanced or unbalanced colloid with balanced or unbalanced crystalloid and assessed whole blood coagulation with thromboelastometry. Method. Venous blood was collected from 12 volunteers in a crossover study. Various combinations of balanced and unbalanced colloids (6% HES 130/0.4 and 4% gelatin) and crystalloids (balanced or non-balanced Ringer’s acetate) with ratio of 1:1 were added to citrated whole blood samples to induce 20 vol.% and 40 vol.% haemodilution. The undiluted and diluted blood samples were analysed with thromboelastometry (ROTEM£) using two activators, tissue thromboplastin without (ExTEM£) or with cytochalasin (FibTEM£). Results. Initiation of coagulation and fibrin formation were delayed at 20 vol.% and 40 vol.% haemodilution in all samples. ® In ExTEM analysis, maximum clot firmness (MCF) was decreased and clot formation time (CFT) prolonged after 40 vol.% haemodilution with balanced Ringer/unbalanced HES combination more than in corresponding gelatin haemodilution. In 40 vol.% haemodilution with unbalanced Ringer/gelatin ® solutions, MCF in FibTEM analysis was significantly stronger than in the Ringer/HES-combinations. Conclusions. The combination of totally balanced colloid and crystalloid solutions has similar coagulation effects to respective unbalanced solutions in vitro. Our finding implies that the totally balanced volume replacement concept offers no additional advantage in acutely bleeding patients with decreased coagulation capacity. The more important factor is the characteristic of the colloid solution. References. 1. Boldt J, Wolf M, Mengistu A. A new plasma-adapted hydroxyethyl starch preparation: in vitro coagulation studies using thromboelastography and whole blood aggregometry. Anesth Analg 2007; 104: 425-430. O-30 Increased use of fibrinogen is associated with reduced postoperative bleeding and transfusion of allogeneic blood products Lars Folkersen, Michael Hinrichs, Carl-Johan Jakobsen Aarhus University Hospital, Skejby, Aarhus, Denmark Introduction. Postoperative bleeding and the subsequent transfusion of allogeneic blood products remain a dilemma of concern in cardiac surgery. The purpose of the study was to evaluate whether introduction of augmented blood coagulation monitoring (ROTEM®) [1] together with a treatment algorithm could reduce the use of allogeneic blood products. Method. A historical prospective study of 1,746 consecutive cardiac surgery patients was carried out. Patients were grouped into 4 six month periods: 1.-2008 (Control); 2.-2008 (discussion new initiative); 1.-2009 (new approach implemented); 2.-2009 (monitoring and algorithm fully implemented. The major

collected parameters were use of fibrinogen together with postoperative drainage, transfusion of blood products and reoperations. Results. Eighteen patients were excluded due to severe peroperative bleeding (13 requiring more than 10 units of allogeneic SAGM blood) and 5 peroperative deaths, leaving 1,733 patients in the study. The number of patients receiving blood and blood products decreased from 31.8% to 29.5% (not statistically significant). The table demonstrates that average volumes of transfused SAGM, plasma and platelets were statistically significantly lower together with significant lower postoperative drainage. Use of fibrinogen increased significantly 2 from 2.8% to 13.5% (P<0.0001, Ȥ -test). Table 1. Postoperative drainage and transfusions Type SAGM Plasma Platelets Drainage

1-2008 324 ± 918 307 ± 829 128 ± 322 852 ± 997

2-2009 133 ± 314 154 ± 388 81 ± 204 708 ± 684

P <0.0001 0.0008 0.0156 0.0183

Discussion. Our results demonstrate a strong association between fibrinogen administration and reduced postoperative bleeding and transfusion. However, the high frequency of fibrinogen administration stresses the need for an evaluation of ® the ROTEM monitoring and associated treatment algorithm. Reference. 1. Görlinger K, et al: Perioperative coagulation management and control of platelet transfusion by point-of-care platelet function analysis. Transfus Med Hemother 2007; 34: 396-411. O-31 Mechanical cell salvage and off-pump coronary artery bypass grafting surgery: a systematic review and metaanalysis Adler Ma, Andrew Smith, Peter Alston, William Brindle, Gillian Burton, Ilinda Manelius, Stuart Gallacher, Fong Cheng Hong, Weiyang Ho University of Edinburgh, Edinburgh, United Kingdom Introduction. Mechanical cell salvage (MCS) reduces blood loss and transfusion in on-pump coronary artery bypass grafting (CABG) surgery [1]. However, blood loss and transfusion is less in off-pump compared to on-pump CABG surgery and so MCS may be of less clinical value in this setting [2]. The aim of this study was to undertake a systematic review and meta-analyses to determine the effectiveness and safety of MCS in patients undergoing off-pump CABG surgery. Method. Systematic review of the literature identified four randomized controlled trials (RCTs). The RCTs were subjected to meta-analyses for the following outcomes: postoperative blood loss, allogeneic transfusions and thromboembolic complications. Results. There was insufficient data for inclusion of all RCTs in each meta-analysis. Blood loss data were presented in differing formats that did not permit meta-analysis. MCS was associated with no reduction in the individual components of transfusion, namely red cells, fresh frozen plasma or platelets. However, when pooled, MCS significantly reduced the overall risk of allogeneic blood component transfusion (risk ratio 0.75; 95% CI 0.60-0.93; P=0.01). No association between MCS and thromboembolic complications was found. Population sizes of all meta-analyses were small ranging from 120 to 169. Conclusions. Although MCS was associated with less overall transfusion, it was not associated with any reduction in the transfusion of the individual blood components. Type II statistical error as a result of the small population sizes, may explain these findings. Appropriately powered RCT is required

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to determine the clinical effectiveness and safety of MCS in offpump CABG surgery. References. 1. McGill N, O’Shaughnessy D, Pickering R, et al. Mechanical methods of reducing blood transfusion in cardiac surgery: randomised controlled trial. BMJ 2002; 324: 1299-1305. 2. Carless PA, Henry DA, Moxey AJ, et al. Cell salvage for minimising perioperative allogeneic blood transfusion. Cochrane Database Syst Rev 2006; 4: CD001888. O-32 Tranexamic acid is associated with less blood transfusion in off-pump coronary artery bypass grafting surgery: a systematic review and meta-analysis William Brindle, Peter Alston, Gillian Burton, Stuart Gallacher, Weiyang Ho, Fong Cheng Hong, Adler Ma, Ilinda Manelius, Andrew Smith University of Edinburgh, Edinburgh, United Kingdom Introduction. Tranexamic acid reduces blood loss and transfusion in on-pump coronary artery bypass grafting (CABG) surgery [1]. However, blood loss and transfusion is reduced in off-pump compared to on-pump CABG surgery and so the clinical value of tranexamic acid may be less in this setting. The aim of this study was to undertake a systematic review and meta-analysis to determine the effectiveness and safety of tranexamic acid in off-pump CABG surgery. Method. Systematic review identified eight randomized controlled trials (RCTs). The RCTs were subjected to metaanalysis for the following outcomes: 24-hour blood loss, postoperative allogeneic transfusions and thromboembolic complications. Results. A lack of appropriate data limited meta-analysis on blood loss. Tranexamic acid was associated with a significantly less 24 h blood loss (mean difference -259; 95% CI -468 – -51 mL; P=0.01). Tranexamic acid significantly reduced the overall risk of allogeneic blood component transfusion (risk ratio 0.47; 95% CI 0.33-0.66; P<0.0001) and packed red blood cell transfusions (risk ratio 0.51; 95% CI 0.36-0.71; P=0.0001). No association was found between tranexamic acid and MI, stroke or pulmonary embolism. Population sizes of meta-analyses ranged from 466 to 544. Conclusions. Tranexamic acid reduces blood loss and transfusion following off-pump CABG surgery. No association with adverse events was found with tranexamic acid but our meta-analysis had too small a sample size to detect rare but clinically significant thromboembolic events. An appropriately powered RCT is required to determine the clinical effectiveness and safety of tranexamic acid in off-pump CABG surgery. References. 1. Henry DA, Carless PA, Moxey AJ, et al. Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion. Cochrane Database Syst Rev 2007; 4: CD001886. O-33 Clinical utility of platelet function testing in patients undergoing routine cardiac bypass graft surgery M Reece, Alan Ashworth, E Salviz, A Hastings, R Luddington, S Nair, Martin Besser, Andrew Klein Papworth Hospital, Cambridge, United Kingdom Introduction. Post-op bleeding in cardiac surgery is multifactorial, with platelet dysfunction frequently cited as the cause. Therefore, platelet concentrate is often transfused

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despite a normal numerical count. A new point of care testing device, Multi Electrode Analyser (MEA) has been developed. We carried out a prospective observational study comparing platelet function with blood transfusion. Method. Patients undergoing elective coronary artery bypass graft (CABG) surgery were included in the study. At four timepoints (induction, 20 min on cardiopulmonary bypass (CPB), chest closure and ITU arrival), blood samples were drawn. A full blood count was made and MEA was performed immediately after sampling. Results. Forty five patients were included in the study, of whom 28.9% were transfused allogeneic blood. There were no reexplorations or deaths. All MEA indices were significantly reduced from baseline (97.5 ±25) after institution of CPB (55 ± 23, P=0.001). The MEA indices were significantly lower in the transfused (65.3 ± 18.2) versus the non-transfused patients (89.0 ± 38.6) at chest closure (P=0.009). At this time, there was no significant difference in the platelet count (125 ± 40 versus 115 ± 38, P=0.43). No patient who received a blood transfusion had MEA >100. Discussion. In this study, MEA demonstrated reduced platelet function 20 minutes after institution of CPB. In addition, there was a significant difference in mean MEA parameters at chest closure between patients who were subsequently transfused compared to those who were not. This difference was not associated with a difference in mean platelet count. MEA has potential for use as part of postoperative blood conservation algorithms. We now propose to carry out a prospective study in a larger cohort. O-34 Multiplate platelet function analysis to quantify platelet inhibition in patients treated with anti-platelet agents undergoing cardiac surgery Andrew Richardson, Angela Wright, Maria Filippaki, Ravi Gill Southampton University Hospitals NHS Trust, Southampton, Hampshire, United Kingdom Introduction. Patients awaiting cardiac surgery are often maintained on anti-platelet medications. Multiplate whole blood aggregometry (WBA) examines platelet aggregation by measuring changes in impedance between two electric wires immersed in blood, occurring after a platelet agonist is added to the blood sample [1]. We assessed whether it can detect clinically significant platelet inhibition in patients on aspirin and clopidogrel undergoing cardiac surgery. Method. A service evaluation was performed. Type and urgency of surgery, type and duration of cardiopulmonary bypass, antiplatelet therapy, Multiplate platelet function test results, baseline and perioperative coagulation characteristics, transfusion requirements and post-operative bleeding were analysed retrospectively for 45 cardiac surgical patients. Results. Thirty five patients were identified who had taken aspirin, 17 of whom had also received clopidogrel within 5 days prior to surgery. Four patients were subsequently removed due to abnormal thrombin receptor activating peptide-6 test. With aspirin alone, 8/14 showed inhibition on the arachidonic acid pathway (AA-ASPI test). 6/8 (75%) of these patients required intra-operative platelet transfusion compared to 3/6 (50%) of those showing no inhibition. With both aspirin and clopidogrel 15/17 (88%) displayed inhibition on either the AA or ADP pathway. 12/15 who were inhibited on either pathway required platelets (8/15 intra-operatively), compared to 0/2 displaying no inhibition.

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Discussion. Multiplate testing may help to identify patients with actual rather than assumed platelet inhibition and may be useful to predict perioperative platelet transfusion requirements in patients undergoing cardiac surgery.

Reference. 1. Tóth O, Calatzis A, Penz S, et al. Multiple electrode aggregometry: a new device to measure platelet aggregation in whole blood. Thromb Haemost 2006; 96: 781-788.

Oral Session VI – Cardiac Surgery in the Elderly O-35 Cardiac surgery in patients 80 years and over: a predictive model for outcome Francesca Cislaghi, Anna Maria Condemi, Alberto Corona Cardioanaesthesia Department, Luigi Sacco Hospital, University of Milano, Milano, Italy Introduction. With the progressive aging of western populations, cardiac surgeons are increasingly faced with elderly patients. Method. On all the patients, aged •80 yr, admitted to our postoperative ICU since January 1994 through December 2009, we collected demographic profiles, operative data and outcomes. A logistic regression model was set up to assess predictors of hospital outcome. Results. A total of 498 patients (4.8%), 53.5% males and with a median (IQR) age of 83 (82-85) were admitted. Table 1. The outcome predictors. Age (yrs) Gender (F/M) IDDM (no/yes) COPD (no/yes) Chronic renal failure (no/yes) Hypertension (no/yes) Arteriopathy (no/yes) Ejection fraction (no/yes) CABG (yes/no) Valve replacement (yes/no) Combined operations (yes/no) Emergency surgery (yes/no) Cardiopulmonary-by-pass-time (‘) Aortic cross clamp time (‘) Red blood cell transfusions (#) Fresh frozen plasma (#) Mechanical ventilation (h)

ODD-Ratio 1.26 0.59 0.90 0.81 0.78 0.89 0.75 0.75 0.91 0.22 1.91 10.1 1.55 1.25 1.31 1.34 1.11

95% IC (0.8-1.6) (0.2-04) (0.4-2.6) (0.3-2.3) (0.3-1.8) (0.4-1.9) (0.2-1.6) (0.2-1.6) (0.8-1.1) (0.1-1.1) (0.4-8.9) (3.5-11) (1.1-1.9) (1.1-1.7) (1.2-2.5) (1.1-2.2) (0.8-1.2)

P 0.230 0.100 0.990 0.720 0.564 0.656 0.776 0.776 0.181 0.060 0.423 0.000 0.010 0.020 0.030 0.032 0.785

Conclusions. Emergency surgery, number of red blood cells and fresh frozen plasma transfusion units, together with longer aortic cross-clamp and cardiopulmonary by-pass times, are the strongest predictors of hospital outcome in the elderly patients undergoing heart surgery. O-36 Survival of patients aged 80 or more undergoing cardiac anaesthesia Francesca Cislaghi, Anna Maria Condemi, Alberto Corona Cardioanaesthesia Department - Luigi Sacco Hospital University of Milano, Milano, Italy Introduction. The advancing age of the population in the western world, together with improvements in surgical techniques and postoperative care have resulted in an increasing number of very elderly patients undergoing cardiac operations. Method. On all the patients, aged at least 80 years or more, admitted to our post-operative ICU since January 1994 through December 2009, we collected demographic profiles, operative

data and short and long-term outcomes. SPSS 13.1 was used for statistical analysis and P<0.05 was considered the level of significance. Results. A total of 498 patients (4.8%), 53.5% males and with a median (interquartile range, IQR) age of 83 (82-85) were admitted to our post-operative ICU over the study period. IDDM was recorded in 19.6% of the population, COPD in 13.8%, hypertension in 64.5%, chronic renal failure in 21.7% and arteriopathy in 37.9%. Of the total population, 51.6% with a median (IQR) pre-operative Cardiac Risk Score of 7 (5-8) underwent a coronary-artery by-pass grafting (CABG) surgery, whereas 20.7% with a preoperative median (IQR) NYHA of 3 (2.25-3) needed a valve replacement (VR) and 16.1% combined (CABG + VR) operations. Moreover, 11.6% underwent other types of cardiac and aortic surgery. Overall median (IQR) postoperative mechanical ventilation (MV) length was 15 (10.75-22) h. while no statistically significant difference was recorded in terms of MV duration among the four surgical groups. Overall recorded mortality rate was 10%, with 7.7% for CABG and 12.6% for VR (P=0.388). Kaplan Meier curves showed no differences in survival likelihood at 28th (Log Rank=0.404, th th P=0.817) 60 (Log Rank=0.707, P=0.702) and 90 (Log Rank=0.742, P=0.690) days after surgery among the different surgical groups. Conclusions. The outcome after heart surgery for octogenarians is excellent; the operative risk is acceptable and the late survival rate is good. Therefore, cardiac surgery should not be withheld on the basis of age alone. O-37 Transarterial or transapical approach for transcatheter aortic valve implant (TAVI): differences in population and outcomes Luca Salvi, Paolo Maniglia, Glauco Juliano, Cristina Beverini, Erminio Sisillo Dept. of Anaesthesia & ICU. IRCCS Centro Cardiologico Monzino, Milano, Italy Introduction. During a period of 20 months, trans-catheter aortic valve implant (TAVI) was attempted in 101 patients (pts). Transarterial or transapical approach was chosen on the basis of angiographic, CAT scanning and echocardiographic data. Method. We retrospectively reviewed our database for differences in patients’ demographic and preoperative characteristics as well as outcomes. Data are presented as mean ± SD or relative frequencies; two-tailed Fisher’s exact test or t-test was used for comparison between groups. A value of P”0.05 was considered significant. Results. Transarterial (a) (n=48) and transapical (A) (n=53) patients were different for body weight: 71±15 vs. 62±9 kg (P=0.000), previous PCI: 14% vs. 33% (P=0.03), previous cardiac surgery: 12% vs. 39% (P=0.002) and mitral regurgitation • grade 2: 18% vs. 37% (P=0.04), respectively for (a) and (A). Differences in outcome included 30-days survival: 44 vs. 53 pts. (P=0.047), length of stay in the ICU: 1.5±0.7 vs. 3.2±2 days (P=0.000), and in the hospital: 7.3±4.1 vs. 11.2±9.3 days (P=0.01), new episodes of atrial fibrillation: 2 vs. 12 (P=0.007)

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and rate of vascular complications: 8 vs. 0 (P=0.000), respectively for (a) and (A). Discussion. Differences in the selection of the pts can lead to different outcomes after (a) or (A) TAVI and have recently been assessed [1]. At our institution, a surgical team trained in catheter skills decides for the best option and is able to perform both approaches; furthermore all the pts are operated on in a dedicated hybrid room within the theatre and with the assistance of the anaesthetist caring for the pts during surgery and in the ICU. This uniform behaviour, therefore, can avoid bias created by performer (cardiologist vs. surgeon), hospital site (cath. lab. vs. theatre) and anaesthesia technique (general vs. local). Reference. 1. Bleiziffer S, Ruge H, Mazzitelli D et al. Survival after transapical and transfemoral aortic valve implantation: Talking about two different patient populations. J Thorac Cardiovasc Surg 2009; 138: 1073-1080. O-38 Percutaneous versus surgical aortic valve replacement: improved outcome and reduced need for intensive care in octogenarians Hannah Wilson, Niranjan Jayasheela, Sujatha Kesavan, Andreas Baumbach, Mark Turner, Stephen Linter, Ian Ryder Bristol Heart Institute, Bristol, United Kingdom Introduction. Transcatheter aortic valve implantation (TAVI) is an alternative to surgical aortic valve replacement (SAVR) in high risk octogenarians [1]. Method. We reviewed ICU and Coronary Care Unit (CCU) charts of 27 consecutive TAVI patients over 80 years old from Jan. 08 to Nov. 09. Comparative data was obtained from the cardiac surgical (PATS) database for 77 consecutive first time SAVR patients aged over 80 from 1996 to 2009. Results. Postoperatively, 59% of the TAVI patients were managed on ICU and 41% went directly to CCU. For SAVR, mean ventilation time was 2 days. TAVI mean ventilation time was 5 hours. Median ICU stay for TAVI was 1 day while SAVR was 11 days. Mean ICU costs were £617 per TAVI patient compared to £11,495 for SAVR [2]. Inotropes Intra-aortic balloon pump Pulmonary artery catheter CVA- permanent deficit Tracheostomy ± reintubation and ventilation CVVH In hospital death

TAVI % (Number) 7 (2) 0 0 3.7 (1) 0

SAVR % (Number) 45.5 (35) 2.6 (2) 2.6 (2) 2.6 (2) 7.8 (6)

0 0

2.6 (2) 6.5 (5)

Discussion. TAVI reduces requirements for post operative ICU with potentially significant cost savings. ICU may be avoided altogether in many patients. References. 1. Kapadia SR, Tuzcu EM. Transcatheter aortic valve implantation. Curr Treat Options Cardiovasc Med. 2009; 11(6): 467-475. 2. http://www.dh.gov.uk/prod_consum_dh/groups/dh_digitalassets/ documents/digitalasset/dh_098951.xls: NHS Reference costs 2007-8.

O-39 Octogenarians and younger patients for cardiac surgery: comparison of risk factors and outcome Bishnu Panigrahi, Sanjay Goel, Kanwar Aditya Baloria, Nandini Selot Max Heart and Vascular Institute, Delhi, India Introduction. An ever increasing need for cardiac surgery in the elderly demands constant re-evaluation of risk factors that may be peculiar for this subset of the population. Method. We retrospectively analysed 2,390 patients undergoing cardiac surgery over a period of 4 years. Of these 2,390, 170 patients were octogenarians (age >80 year). We compared the perioperative risk factors between the octogenarians and younger patients. Also we studied the effect of these risk factors on the mortality among the two groups. Results. We found comparable mortality among the octogenarians and younger age groups (7% and 6% respectively). At multivariate analysis, peripheral vascular disease (OR 3.58), atrial fibrillation (OR 6.09), postoperative neurological dysfunction (OR 4.68), urgent surgery (OR 1.92) and high EuroSCORE (>6, (OR 2.04) were independent predictors for mortality among the octogenarians. They also had a significantly higher incidence of hypertension, diabetes mellitus, NYHA III/IV, peripheral vascular disease, cerebrovascular disease, left main disease, atrial fibrillation, acute renal dysfunction, and perioperative MI. 78% of patients in the octogenarian group had undergone CABG alone (58%) or CABG with valve surgery (21%). Table. Multivariate predictors for complications and mortality in Octogenarians. Multivariate Predictors AF Renal dysfunction Periop- MI Neurological dysfunction Urgent surgery EuroSCORE >6 Peripheral vascular disease

Complications (Odds ratio) 2.1 2.3 11.2 4.7 NS NS 4.1

Mortality (Odds ratio) 6.09 NS NS 4.60 1.92 2.02 3.58

Conclusion. Despite increased morbidity among the octogenarians, mortality was similar compared to the younger patients. This could be due to improved surgical technique, anaesthetic technique, monitoring and intensive care. Surprisingly, we found a slightly higher mortality in younger age group. This is because 71% of patients among younger age group had undergone valve surgery with a higher mortality. References. 1. Schmidtler FW, Tischler I, Lieber M, et al. Cardiac surgery for octogenarians - a suitable procedure? Twelve-year operative and post-hospital mortality in 641 patients over 80 years of age. Thorac Cardiovasc Surg 2008; 56: 14-19. 2. Stamou SC, Dangas G, Dullum MK, et al. Beating heart surgery in octogenarians: perioperative outcome and comparison with younger age groups. Ann Thorac Surg 2000; 69: 1140-1145.

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Oral Session VII – Cerebral Monitoring & Protection O-40

O-41

Effects of sevoflurane on cerebral blood flow velocity, oxygen extraction and dynamic autoregulation during cardiopulmonary bypass

Cerebral oxygen saturation measured by near-infraredspectroscopy does not reliably detect the cerebral status Werner Baulig, Daniel Borer

Björn Reinsfelt, Sven-Erik Ricksten, Anne Westerlind Sahlgrenska University Hospital, Göteborg, Sweden Introduction. Sevoflurane (Sevo) is a commonly used anaesthetic agent during cardiopulmonary bypass (CPB). Previous results on the effects of Sevo on autoregulation of cerebral blood flow (CBF) in man are controversial. We investigated the effects of Sevo-induced burst suppression on cerebral blood flow velocity (CBFV), cerebral oxygen extraction (COE) and dynamic autoregulation during moderate hypothermic CPB. Method. Sixteen patients undergoing elective cardiac surgery were included. The patients were anaesthetized with fentanyl, nitrous oxide and droperidol prior to and during CPB. During CPB with stable hypothermia (34OC) mean arterial blood pressure (MAP), CBFV, right jugular bulb oxygen saturation (SjO2), jugular venous pressure (JVP) and EEG were continuously measured. Autoregulation i.e. cerebral perfusion pressure (CPP=MAP-JVP) vs. CBFV or COE (SaO2-SjO2/SaO2) were evaluated by stepwise changes in MAP from 40-80 mmHg before (control) and during Sevo which was delivered via the pump oxygenator in concentrations to induce burst suppression EEG (range 4-6 bursts/minute) [1]. Effects of Sevo on the relationship between CPP and CBFV or COE compared to control were tested using paired t-test statistics. Results. Sevo significantly reduced CBFV (Fig) (P<0.05), and COE (P<0.05) by 21% and 19% respectively. Dynamic pressure-flow autoregulation was impaired compared to control (P<0.05). Values are mean ± SEM

University Hospital Zurich, Institute of Anaesthesiology, Zurich, Switzerland Introduction. The aim of this study was to evaluate bilateral near-infrared-spectroscopy in detecting cerebral ischaemia during aortic arch surgery in emergency patients suffering a Standford type A aortic dissection. Method. During the period of 2007 to 2008 patients with acute Stanford type A aortic dissection were included. Before induction of anaesthesia two sensors of the INVOS 5100 and a BIS sensor with four elements were attached on the forehead bilaterally. Regional oxygen saturation (rSO2) of left and right forehead, BIS, cardiac index, mean arterial pressure, pulse rate, arterial oxygen saturation, mixed venous oxygen saturation, haematocrit, blood temperature were detected continuously o during surgery. Patients were cooled to 20 C.. Antegrade cerebral perfusion was performed by perfusing the right carotid artery using a bypass connected to the right brachial artery. Simple regression analysis of absolute and relative values of rSO2 was performed. Results. There were 11 adult patients (age 38 - 79 years). Nine patients fully recovered after the procedure, two patients suffered severe neurological deficit and one of them died. rSO2 on the left side was significantly reduced in all patients compared to rSO2 on the right side. Decreased temperature resulted in significantly decreased rSO2 values. Additionally relative rSO2 were significantly influenced by cardiac index and mixed venous oxygen saturation. No significant differences in changes of the rSO2 were found between patients with or without neurological deficit. The recovery time of the BIS was considerably prolonged in those patients who suffered neurological deficit (fig 1). Fig 1. rSO2 of the left and right forehead and BIS values during aortic root surgery in one patient who suffered a severe neurological deficit.

Discussion. Burst suppression doses of Sevo decreased both CBFV and COE during moderately hypothermic CPB, indicating loss of metabolic autoregulation of CBF. Dynamic pressure flowautoregulation was impaired by Sevo. A direct cerebral vasodilatory action of Sevo could explain these findings. Reference. 1. Reinsfelt B, Wester,ind A, Houltz E, et al. The effects of isoflurane-induced electroencephalographic burst suppression on cerebral blood flow velocity and cerebral oxygen extraction during cardiopulmonary bypass. Anest Analg 2003; 97: 1246-1250.

Conclusion. Neither absolute nor relative rSO2 measurements could indicate the presence of significant disturbances of cerebral perfusion during aortic root surgery.

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O-42 A national survey of the policy for delirium in UK Cardiothoracic Intensive Care Units (CICU) and introduction of a ‘Delirium Bundle’ to a CICU Coralie Carle, Inese Kutovaja, Helen Saunders Lancashire Heart Centre, Blackpool, United Kingdom Introduction. Delirium has an incidence of 11-52% in CICU patients and is associated with increased mortality, hospital readmissions and long-term patients’ inability to concentrate. A confusion assessment method for ICU (CAM-ICU) has been validated as a screening tool to identify delirious patients. We conducted a national survey of delirium policy in all CICUs and reviewed the incidence and management of delirium in our own CICU. We subsequently designed and introduced a ‘Delirium Bundle’, incorporating the CAM-ICU, to our CICU. Method. All the UK CICUs were contacted and asked: 1. Do you routinely screen your patients for delirium? 2. Do you have any guidelines for the treatment of delirium? We then, with hospital ethics committee approval, carried out delirium screening using CAM-ICU on our CICU patients. Results. Of the 38 UK CICUs contacted: one unit (2.6%) routinely screened their patients for delirium; four units (10.5%) were in the process of introducing delirium screening; seven units (18.4%) had a delirium management guideline in place and a further five units (16.1%) were in the process of developing a guideline. On our unit, we carried out 48 CAM-ICU assessments on a total of 30 patients. 29.5% of these CAM-ICU assessments were positive for delirium. In total 20% of patients screened were positive for delirium. Discussion. When designing our ‘Delirium Bundle’ we targeted three key areas: prevention, diagnosis and management. Following an eight-week campaign (posters, small group teaching, PowerPoint presentations) to educate and raise awareness of the ‘Delirium Bundle’, it was formally introduced to the CICU. Its introduction was supported by a further poster campaign and individual bedside refresher teaching. At present our unit is actively trying to reduce the causes of delirium, is screening all patients for delirium using the CAM-ICU and where appropriate, is following the new treatment guideline. O-43 Effect of N-acetylcysteine on neuron specific enolase levels in jugular bulb blood after cardiopulmonary bypass Engin Husnu Ugur, Nihan Yapici, Turkan Coruh, Zeliha Tuncel, Sinem Yigit Ugur, Zuhal Aykac Siyami Ersek M.D Cardiovascular & Thoracic Surgery Research Hospital, Istanbul/Kadikoy, Turkey

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general anaesthesia, T2: after CPB, and postoperatively in the sixth hour) from the jugular bulb catheter which was placed in the internal jugular vein retrograde before surgery. The serum samples were assayed for NSE levels by using ECLIA (Electrochemiluminescence Immunoassay). Results. Serum NSE levels were significantly increased after th CPB and decreased postoperatively at the 6 hour in both groups. Between the C and N groups the NSE levels at TO, T1, T2 time intervals were not significantly difference. Discussion. These findings suggested that NAC did not have a neuroprotective and anti-inflammatory effect in patients undergoing CABG. As the blood sampling was drawn in early periods after CPB, the NSE levels of the late period after CPB should also be investigated. O-44 Predictors of decreased cerebral oxygenation during onpump cardiac surgery Tatiana Klypa, Alexander Shepelyuk Hospital ʋ 119, Moscow, Russian Federation Introduction. Cerebral complications are still challenging problems in cardiac surgery, being the cause of a 5th of deaths, an increase in ICU and hospital stay and increased cost of treatment. Method. 461 patients undergoing on-pump cardiac surgery in 2007-2009 were included (59±1 yr, NYHA 3, 4±0.3, CPB 98±2 min, cross-clamp time 60±13 min (mean±SEM)) and were divided into 2 groups, Group 1 with decrease in cerebral oxygenation (CO) below 45% (n=152) during CPB and Group 2 without CO decrease (n=309). Groups were similar in age, type of operation, CPB and cross-clamp time, the initial state, anaesthetic and CPB technique. There were 3 types of cardioplegia, Calafiori technique, crystalloid and Custodiol. All patients had invasive monitoring of haemodynamics, noninvasive cerebral oxygenation (infrared spectrometry, Somanetics) and depth of anaesthesia. Data of preoperative examination was also analysed. Student’s t-test was used; P<0.05 was considered significant. Results. 13% patients of Group 1 and 3% of Group 2 had postoperative cerebral complications (P<0.05). Patients of Group 1 had initially lower (P<0.05) Hb (133±3 and 141±2 g/L), more frequent internal carotid stenosis (>50%) - 18±3 and 10±2% respectively (P<0.05), also differences of Hb and ɊɋɈ2 during CPB (table). There was no difference in arterial pressure, central venous pressure, lactate, blood glucose or partial pressure and transport of oxygen. Groups 1 and 2 underwent cardioplegia: by the Calafiori technique - 57% and 72% (P<0.05), crystalloid - 34% and 15% (P<0.05) or Custodiol – 10% and 13 %, respectively. 30 min CPB

Introduction. This study investigated the neuroprotective and anti-inflammatory effect of N-acetylcysteine (NAC) on cardiopulmonary bypass (CPB) patients by measuring the neuron specific enolase (NSE) levels in the jugular bulb blood. Method. Forty patients undergoing coronary artery bypass grafting (CABG) were randomly divided into a study group (N) (n=20), given 100 mg/kg bolus NAC (0.9% isotonic NaCl, 250 mL in 30 min, iv.) and 20 mg kg-1 h-1 NAC (0.9% isotonic NaCl 500 mL, iv.) after induction of general anaesthesia, and a control group (C) (n=20) given a saline bolus (250 mL in 30 min, iv.) and a 100 ml/h iv. infusion. Serum samples were collected at defined time intervals (TO: before CPB, T1: after the induction of

Gr 1 Gr 2

60 min CPB

Hb

Ht

ɊɋɈ2

Hb

Ht

ɊɋɈ2

88±1.2 94.1±0.9̅

25.7±0.4 28.1±0.2̅

25.4±0.3 27±0.7̅

84.4±2.3 93.7±1.6̅

25.6±0.4 28.3±0.3

24.6±0.5 25.8±0.4̅

Conclusions. Intraoperative decrease of cerebral oxygenation below 45% is a predictor of cerebral complications. Patients with a preoperative level of Hb less than 130 g/L and internal carotid artery stenoses more than 50% are at risk of cerebral complications. Among patients in a risk group it is necessary to avoid undue haemodilution and hypocapnia during CPB. Calafiori cardioplegia may be preferable in this group.

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Oral Session VIII – Drugs & Fluids O-45 Target-oriented inotropic support after myocardial revascularization with prolonged aorta cross-clamping 1

Lev Krichevskiy , Vladislav Rybakov

2

1

Research Institution of General Reanimatology, Moscow, 2 Russian Federation, Filatov's Hospital N15, Moscow, Russian Federation Introduction. Inotropic therapy may be necessary after prolonged aorta cross-clamping (ACC). Left ventricular fractional area change (FAC) is the usable echocardiographic parameter [1]. We evaluated FAC as a possible target parameter for the inotropic support after prolonged ACC. Method. After informed consent 63 patients (pts) undergoing coronary surgery with ACC time more than 70 (102±25) min were randomized into two groups. In group 1 (32 pts) standard haemodynamic management after cardiopulmonary bypass (CPB) was used. If the cardiac index (CI) was less than 2.5 -1 -2 litre·min ·m when right atrial pressure (RAP) or pulmonary artery wedge pressure (PAWP) was more than 15 mmHg, inotropic support was started or doses of cardiotonics were extended. In group 2 (31 pts) the post-CPB inotropic therapy was oriented on the FAC value of >50%. The inotropic support was finished in both groups in the stable haemodynamic status without FAC control. P<0.05 was considered significant. Data are given as mean± standard deviation. Results. Post-CPB haemodynamic data are presented in the table. Post-CPB parameters closure) FAC, % CI litre·min-1·m-2 PAWP mmHg RAP mmHg

(sternum

Dopamine (dobutamine) Pg·kg-1·min-1

Group 1

Group 2

P

47±14 2.6±0.9 13±3.8 8±3.3 3.3±2.2

58±12 3.3±1.1 9.6±2.9 6.5±2.6 5.7±2.3

0.032 0.014 0.003 0.101 0.001

Postoperative duration of inotropic support in group 2 (8.2±3.8 hours) was significantly shorter than in group 1 (19.4±17.6 hours) (P=0.028). Discussion. FAC is the effective target parameter for inotropic support after prolonged ACC. Target-oriented inotropic support results in acceleration of the rate of postoperative haemodynamic recovery. Reference. 1. Odell DH, Cahalan MK. Assessment of left ventricular global and segmental systolic function with transesophageal echocardiography. Anesthesiol Clin 2006; 24: 755-762. O-46 Norepinephrine causes a pressure-dependent volume decrease in clinical vasodilatory shock

plasma

Andreas Nygren, Bengt Redfors, Anders Thorén, Sven-Erik Ricksten Sahlgrenska University Hospiltal, Gothenburg, Sweden Introduction. Recent experimental studies have shown that a norepinephrine-induced increase in blood pressure induces a loss of plasma volume, particularly under increased microvascular permeability. We studied the effects of norepinephrine-induced variations in mean arterial pressure

(MAP) on plasma volume changes and systemic haemodynamics in patients with vasodilatory shock. Method. Twenty-one mechanically ventilated patients who required norepinephrine to maintain MAP •70mmHg because of septic/postcardiotomy vasodilatory shock were included. Norepinephrine dose was randomly titrated to target MAPs of 60, 75 and 90mmHg. At each target MAP, data on systemic haemodynamics, haematocrit, arterial and mixed venous oxygen content and urine flow were measured. Changes in plasma volume were calculated as: 100 x (Hctpre/Hctpost – 1)/(1Hctpre), where Hctpre and Hctpost are haematocrits before and after intervention. Results. Norepinephrine doses to obtain target MAPs of 60, 75 -1 and 90mmHg were 0.20±0.18, 0.29±0.18 and 0.42±0.31 μg kg -1 min , respectively. From 60 to 90mmHg, increases in cardiac index (15%), systemic oxygen delivery index (25%), central venous pressure (CVP) (20%) and pulmonary artery occlusion pressure (33%) were seen, while intrapulmonary shunt fraction was unaffected by norepinehrine. Plasma volume decreased by 6.5% and 9.4% (P<0.0001) when blood pressure was increased from 60 to 75 and 90mmHg, respectively. MAP (P<0.02) independently predicted the decrease in plasma volume with norepinephrine but not CVP (P=0.19), cardiac index (P=0.73), norepinephrine dose (P=0.58) or urine flow (P=0.64). Conclusions. Norepinephrine causes a pressure-dependent decrease in plasma volume in patients with vasodilatory shock most likely caused by transcapillary fluid extravasation. O-47 Preoperative levosimendan administration: what is the vascular payment during anaesthesia? Boris Akselrod, Nina Trekova, Irina Tolstova, Armen Bunatian NRCS, Moscow, Russian Federation Introduction. The purpose of the study was to evaluate the influence of preoperative levosimendan administration on the vascular system during operation. Method. Twenty one patients with dilated cardiomyopathy were randomized into 2 groups. In Gr. 1 (n=11) levosimendan (Simdax®,Orion) was administered in dose 0.05-0.1 mg kg-1·min1 during 24 h. Infusion was stopped 36-48 h. before operation. Gr. 2 (n=10) was the control group. Mitral valve replacement was performed and tricuspid regurgitation was corrected. In both groups haemodynamics were assessed using the transpulmonary thermodilution method (PiCCO, Pulsion). The microcirculation was evaluated by wavelet transformation of the laser Doppler flowmetry. Laser signal from the index finger, arterial pressure, peripheral and core temperatures were simultaneously recorded. Results. The recorded haemodynamic data showed a good cardiotonic effect of preoperative administration of levosimendan. Stroke volume index was more in Gr. 1 during the main stage of operation. Baseline mean arterial pressure and system vascular resistance index, after induction of anaesthesia and at the end of operation were significantly lower in Gr. 1. Global end-diastolic volume index was also less in Gr. 2 1 after induction of anaesthesia (626±89.5 mL/m vs. 710±96.7 2 2 mL/m , P=0.053) and at the end of operation (825±93.6 mL/m 2 vs. 920±102.4 mL/m , P=0.039). However hypotension and norepinephrine doses between the two groups did not differ. Mean volume of intravenous infusion during induction of anaesthesia was more in Gr. 1: 3.4±1.10 mL/kg versus 2.5±0.85 mL/kg (P=0.051). In Gr. 1 total perfusion at all stages of operation was considerably greater then in Gr. 2 reflecting the

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positive influence of levosimendan on the microcirculation. During cardiopulmonary bypass, total perfusion was greater in Gr. 1 then Gr. 2 at 30 min (19.8±8.23 perfusion unit (p.u.) vs. 8.7±5.50 p.u., P=0.002) and at 60 min (13.9±6.51 p.u. vs. 8.3±4.34 p.u., P=0.033). Conclusion. This method of preoperative levosimendan administration resulted in a mild decrease of preload and afterload during anaesthesia that required more volume loading. Preoperative application of levosimendan increased the peripheral microcirculation during operation.

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O-48

Introduction. Levosimendan is a calcium sensitizer inotropic drug and vasodilator that is used for the treatment of heart failure. Previous studies showed its preconditioning effect in cardiac surgery [1]. We aimed to compare the effect of levosimendan and milrinone administered before cardiopulmonary bypass (CPB) on myocardial damage and haemodynamics in high risk patients after cardiac surgery. Method. This was a retrospective single centre study. 21 patient with a preoperative left ventricle ejection fraction ”35% treated either with levosimendan (n = 7) or milrinone (n = 14) were investigated. Infusion of either drug was started before CPB and continued for 12 h. Cardiac index (CI), mixed venous O2 saturation (SvO2), level of lactate, N-terminal pro b-type natriuretic peptide (NT-proBNP) and troponin I were recorded at time points: 1, starting infusion; 2, after 12 h; 3, after 24 h. Comparisons were based on Mann-Whitney U test. Values are expressed as median and range. P<0.05 was deemed to be significant. Results. Demographic, preoperative clinical, EuroSCORE, type of surgery, duration of CPB and aortic cross-clamp, haemodynamics, NT-proBNP and troponin I measured at time point 1 did not differ significantly between levosimendan and milrinone treated patients. Cardiac index improved significantly at time points 2 and 3 compared to time point 1 within both patient groups (P<0.01). Higher CI at time point 3 (3.5 [3.0-3.8] -1 -2 vs. 2.5 [2.4-2.8] litre min m ; P=0.039) and lower concentration of troponin I at time point 2 (3.15 [1.5-12.3] vs. 10.4 [9.2-23.2] -1 Pg L , P=0.043) was found in the milrinone group compared to levosimendan treated patients. Discussion. Pre-treatment with milrinone led to a higher cardiac index and lower troponin I concentration after cardiac surgery compared to levosimendan treated patients. Reference. 1. Tritapepe L, De Santis V, Vitale D, et al. Preconditioning effects of levosimendan in coronary artery bypass grafting–a pilot study. Br J Anaesth 2006; 96: 694-700.

Perioperative haemodynamic effect of preoperative levosimendan in patients with depressed left ventricular function Fabio Sangalli, Tulika Narang, Elisa Bertoli, Chiara Buccino, Leonello Avalli, Roberto Fumagalli Dipartimento di Medicina Perioperatoria e Terapia Intensiva, Monza, Italy Introduction. The aim was to investigate the perioperative haemodynamic effect of preoperative levosimendan in adult cardiac surgical patients with depressed left ventricular function. Method. We enrolled 16 patients with LVEF ”30% scheduled for elective cardiac surgery. Patients were admitted to the ICU the day before surgery, and received an arterial, a central venous, and a pulmonary arterial catheter. After baseline haemodynamic evaluation, a continuous infusion of levosimendan at a fixed rate of 0.1 ȝg kg-1 min-1 was started and continued for 24 h. Haemodynamic parameters were reassessed before CPB (about 20 h after the beginning of levosimendan infusion), after CPB discontinuation, 24 h thereafter and just before removal of the PAC. Inotropes usage, ICU length of stay, and outcome were recorded. Results. Patients mean age was 71±6.5 yr, with a EuroSCORE of 8.2±1.6 (additive) and 11.7±6.4% (logistic). All patients underwent CABG, plus valvular surgery in 6 patients. ICU LOS rd was 3.5±2.2 days. One patient needed an IAB on the 3 postoperative day, and the same patient eventually died from th septic shock on the 12 postoperative day. MAP (mmHg) HR (bpm) CVP (mmHg) WP (mmHg) CO (L/min) SvO2 (%)

Baseline

Pre-CPB

Post-CPB

24 h post-CPB

PAC rem.

85±14 72±10* 5±5 14±7 4.3±0.9* 67.9±8.5

77±12 78±13* 4±4 11±5 5.0±1.1 70.4±6.4

70±9 89±11 11±3* 14±3 5.6±1.2 71.7±5.2

79±9 88±13 8±3 13±3 5.6±1.0 70.6±7.7

78±11 92±15 7±3 13±3 5.1±1.1 69.6±4.3

*ANOVA, P<0.05

Conclusion. In our high risk study population, where levosimendan was added to the standard treatment, we observed a markedly lower mortality (1/16, 6.25%) than predicted by the EuroSCORE, and only one patient needed IAB insertion for haemodynamic support. The contribution of levosimendan to this favourable outcome still needs to be ascertained with a control group.

Pre-treatment with milrinone is superior to levosimendan in improving haemodynamics of patients with impaired left ventricle undergoing cardiac surgery Mindaugas Balciunas, Irina Misiuriene, Robertas Samalavicius Vilnius University Lithuania

Hospital

Santariskiu

Klinikos,

Vilnius,

O-50 Goal-directed fluid management during off-pump coronary artery bypass grafting: is it worth doing? Irina Tolstova, Andrew Yavorovskiy, Boris Akselrod, Nina Trekova, Armen Bunatian Russian National Research Centre of Surgery, Moscow, Russian Federation Introduction. The aim of the study was to determine the efficiency of goal-directed fluid management based on a personal optimal level of global end-diastolic volume index (GEDI) during OPCAB. Method. Forty seven patients scheduled for OPCAB were randomized into 2 groups. In both groups the stroke volume index (SVI) and GEDI were assessed using the transpulmonary thermodilution method (PiCCO, Pulsion). Patients of Gp.I (n=20) received standard volume management, based on routine parameters such as HR, MAP, CVP, urine output and visual

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estimation of the heart. In Gp.II (n=27) in addition to the routine parameters the passive legs raising test was carried out before the induction of anaesthesia. This test was used to indentify the patients who would benefit from fluid loading. Volume challenge was given based on the data received and it was continued up to the moment when the highest possible SVI was reached due to the increase of preload. The achieved value of GEDI was considered as a personal optimum and used as a target value to guide goal-directed therapy throughout the surgery. Results. Mean volume of fluid management in Gp.I was 29.2±4.7 ml/kg, in Gp.II – 37.3±5.2 ml/kg (P<0.001). The received haemodynamic data showed that MAP, SVI and GEDI were significantly greater in Gp.II at most stages of surgery. Dopamine was required less in Gp.II (18% vs. 47%, P<0.05), fewer doses of dopamine were administered in Gp.II (4.1±0.1 -1 -1 vs. 5.6±0.7 μg kg min P<0.001) and the duration of catecholamine dependence was also shorter in Gp.II (11.9±2.1 vs. 13.7±1.9 hours, P<0.05). In three patients of Gp.I (15%) and in two patients of Gp.II (7.4%) haemodynamic disturbances during compression and displacement of the heart led to the urgent start of CPB. There was no significant difference in myocardial ischaemia, duration of mechanical ventilation, postoperative complications and duration of ICU stay. Conclusion. Goal-directed fluid management based on personal optimal level of preload improves haemodynamics, and reduces and shortens cardiotonic support during off-pump coronary artery bypass grafting. O-51 Efficacy and safety of a solution containing half molar sodium lactate infusion on haemodynamic status and fluid balance compared to hydroxylethyl starch 6% during cardiac surgery Cindy Boom, Adi Parmana, Leverve Xavier, Poernomo, Chairil Gani, Syamsul Hadi, Maizul Anwar

Herdono

National Cardiovascular Indonesia

Jakarta,

Center

Harapan

Kita,

Introduction. Controlling haemodynamic status and fluid balance is the mainstay of managing cardiac surgery patients. Patients with reduced myocardial performance may not tolerate the large volume of therapy, therefore small volume administration which can improve haemodynamic performance and maintain adequate fluid balance may be beneficial. This study was aimed to evaluate the efficacy and safety of a solution containing half molar sodium lactate in maintaining haemodynamic stability and fluid balance during CABG surgery compared to HES 6%. Method. In this prospective randomized study, patients were assigned to receive either hypertonic sodium lactate (HSL group: n=47) or hydroxyethyl starch (HES group: n=53). HSL or HES 6% solutions were administered as first loading 3 mL kg BW-1 h-1 after induction followed by a continuous infusion of 1.5 -1 -1 mL kg BW h during surgery and a second loading of 1.5 mL -1 -1 kg BW h following protamine administration. Result. MAP, HR, CVP and PAW exhibited similar evolution in each time of assessment in both groups. Increased cardiac index (CI) was significantly higher in the HSL group (P<0.05). SVRI and PVRI were significantly lower in the HSL group. Wedge pressure was decreased in the HSL group (P<0.05). Total volume infused was insignificantly lower in the HSL group

(2452±705 vs. 2643±692 mL; P>0.05). Urine output was insignificantly higher in the HSL group (2224±953 vs. 2096±1048; P>0.05). Drainage volume was similar in both groups, therefore total fluid loss was higher in HSL group (2931±1240 vs. 2698±1099). The end result was a significantly negative fluid balance in the HSL group. Concomitant drugs use were lower in the HSL group. No adverse events were observed in either group. Conclusion. Infusion of HSL was clearly advantageous in cardiac surgery patients since a superior haemodynamic improvement was obtained with less frequent use of inotropes. There was a higher urine output with lower volume infused in this group, which consequently give a negative fluid balance. O-52 Single high dose sufentanil exerts no haemodynamic effects in patients with ischaemic heart disease Rajesh Bhavar, Jacob R Greisen, Anne E Vester, Lars Folkersen, Erik Sloth, Carl-Johan Jakobsen Aarhus University Hospital, Skejby, Aarhus, Denmark Introduction. Despite sedation, opiates are known to preserve most haemodynamic parameters. However, the impact of a single high dose of sufentanil in patients with ischaemic heart disease is less well described and further new echocardiographic modalities may give a better impression of the effect on cardiac function and circulation. Method. Twenty-five patients were included and acted as their own control. Measurements consisted of invasive haemodynamic monitoring and echocardiographic measurements as in previous studies [1,2]. After establishing haemodynamic monitoring, all patients received a single bolus of sufentanil 2 μg kg-1. Results. The data showed almost no response to the high sufentanil dose. Variable Cardiac Index Stroke volume index Mean arterial pressure Heart rate Peripheral saturation Central venous oxygenation Global Speckle strain (%) Tissue Tracking score index (mm) TD peak systolic velocity (s) E /E’ Ratio E’/A’ Ratio E’ -TD early diastolic velocity (s) A’- TD atrial diastolic velocity (s)

Before 3.04 ± 0.85 48.8 ± 17.1 104 ± 13 64 ± 10 98.3 ± 1.7 73.6 ± 7.0 15.5 ± 3.8 10.4 ± 2.6 4.8 ± 1.1 14.5 ± 6.0 0.92 ± 0.26 5.78 ± 1.56 6.45 ± 1.36

After 3.00 ± 0.64 48.1 ± 15.0 100 ± 17 65 ± 11 99.6 ± 0.7 77.3 ± 6.9 15.3 ± 3.3 10.5 ± 2.8 5.2 ± 1.5 17.3 ± 13.2 0.79 ± 0.32 5.14 ± 1.56 6.75 ± 1.36

P value 0.645 0.631 0.058 0.749 0.001 0.009 0.754 0.863 0.127 0.453 0.019 0.044 0.422

Discussion. The differences in saturations may be fully accredited to the anaesthetic effect as seen with most sedatives and high dose analgesics. The findings of significant lower E”/A” ratio indicating impaired diastolic function call for further studies. Reference. . 1 Jakobsen CJ, Nygaard E, Norrild K, et al. High thoracic epidural analgesia improves left ventricular function in patients with ischemic heart disease. Acta Anaesthiol Scand 2009; 53: 559-564. 2. Larsen JR, Torp P, Norrild K, et al. Propofol reduces tissueDoppler markers of left ventricle function: a transthoracic echocardiographic study. Br J Anaesth 2007; 98: 183-88.

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Oral Session IX – Thoracic Anaesthesia O-53

O-54

Prospective, randomized study of the effects of nondependent lung high frequency positive pressure ventilation on right ventricular function during thoracotomy

Measurements of postoperative airway tissue oxygenation in lung transplantation patients

1

2

3

Mohamed El-Tahan , Reda Hamad , Mona Al Ahmadey , Ehab 3 3 Abou El-Makarem , Alaa Khidr 1

2

King Faisal University, Al Khobar, Saudi Arabia, Prince Sultan 3 Cardiac Centre, Riyadh, Saudi Arabia, Mansoura University, Mansoura, Egypt Introduction. The application of volume-controlled high frequency positive pressure ventilation (HFPPV) to the nondependent lung (NL) during one lung ventilation (OLV) for thoracotomy may provide preservation of right ventricular (RV) function, adequate oxygenation and optimum surgical conditions. Method. After local ethics committee approval and informed consent, 40 patients scheduled for elective thoracotomy were studied. OLV was initiated after pleurotomy, using a tidal volume -1 (VT) 8 mL•kg , inspiratory to expiratory [I: E] ratio 1:2.5 and respiratory rate (R.R) adjusted to achieve a PaCO2 4.5-6 kPa. After 30 min the HFPPV [NL-HFPPV] was applied to the NL for -1 a further 60 min using VT 3 mL•kg , I:E ratio <0.3 and R.R 60/min. The perioperative changes in stroke volume (SVI), pulmonary vascular resistance (PVRI), RV stroke work (RVSWI), and end-diastolic volume (RVEDVI) indices and ejection fraction (REF), oxygen delivery (DO2) and uptake (VO2), shunt fraction (Qs: Qt) were recorded before any surgical manipulation of the lung. Results. The use of NL-HFPPV was associated with lower -2 PVRI, RVSWI [6.2 ± 1.34 vs. 17.6 ± 2.81 g m•m ], RVEDVI [92 -2 ± 27.41 vs. 187 ± 15.24 mL•m ], VO2, and Qs:Qt values and higher SVI, REF [39.9 ± 6.32 vs. 19.8 ± 1.72%] and DO2 values, compared with OLV (P<0.01). There were no recorded events of perioperative hypoxaemia, respiratory or cardiovascular failure. Discussion. We concluded that the use of NL-HFPPV is a safe option and offers improved RV function during thoracic procedures compared with OLV.

Pieter Van der Starre, Gundeep Dhillon, Ramachandra Sista, David Weill, Mark Nicoll Stanford University, Stanford, CA, United States Introduction. Airway tissue hypoxia leading to fibrosis has been a major problem following lung transplantation [1]. Posttransplant airway blood flow depends uniquely on pulmonary artery flow. Recently tissue oximetry became available, using visible light spectoscropy (VLS) [2]. Method. Four healthy surgical patients and 12 single-lung transplantation patients (8 IPF, 4 COPD) 6 months postoperatively were included after IRB approval. Written informed consent was obtained. Using bronchoscopy, an oximetry probe was inserted into the airways and tissue oxygenation was bilaterally measured at different levels. FiO2 was kept at <30%. Results. Mean tissue oxygenation levels were similar in both healthy volunteers (63.7 ± 1.7%) as in the native lung of transplantation patients (65.2 ± 6.7%). In the transplanted lung the values (59.9 ± 4.0%) were significantly lower below the surgical anastomosis (P<0.05). No complications were observed from the instrumentation. Discussion. The results of this study show that tissue oximetry is able to detect levels of ischaemia in airway tissue following lung transplantation. VLS measures oxygenation at the capillary level. Earlier studies showed different values of tissue oxygenation in various organs, like buccal mucosa, bowel mucosa, kidneys, etc [2]. This is the first study showing the normal values of tissue oxygenation at different levels of the airway. Ischaemia of the airway may lead to inflammation, fibrosis and eventually to chronic rejection, known as bronchiolitis obliterans, after lung transplantation. Pulmonary artery blood flow increases in the transplanted lung, shunted away from the native lung, but bronchial arteries are not routinely reconnected. Future studies might be able to show that the detected ischaemia could be prevented by re-establishing bronchial artery blood flow. References. 1. Lukraz H, Goddard M, McNeil K, et al. Microvascular changes in small airways predispose to obliterative bronchiolitis after lung transplantation. J Heart Lung Transplant 2004; 23: 527531. 2. Benaron DA, Parachikov IH, Friedland S, et al. Continuous, noninvasive, and localized microvascular tissue oximetry using visible light spectroscopy. Anesthesiology 2004; 100: 1469-1475. O-55 Does intrathecal diamorphine improve pain relief after thoracic surgery? Gregory McAnulty, Jeremy Cashman, Caroline Keighley-Elstub, Melissa Mellis St George's Hospital, London, United Kingdom Introduction. Intrathecal opioid without local anaesthetic (LA) may be as effective as thoracic epidural analgesia with LA alone whilst avoiding potential complications [1]. We audited the efficacy of intrathecal diamorphine (ITD) as an addition to a

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standard multimodal regimen (morphine patient-controlled analgesia [PCA], LA blocks, oral analgesics) for thoracic surgery. Method. We matched 167 patients who received peroperative lumbar ITD (300 Pg via 25g needle) in addition to a standard analgesic regimen with 167 ‘historical‘ controls according to age, sex and type of operation. The two groups were subdivided into those who underwent open thoracotomy or video-assisted thorascopic surgery (VATS). The acute pain team visited all patients daily and recorded demographic data, pain score, total PCA dose, duration of PCA and any adverse events. Statistical analysis was with Fisher’s exact and Mann-Whitney U tests. Results. Overall ITD enhanced analgesic efficacy in terms of mean [SD] time (h) using PCA (33.8 [19.6] vs. 39.4 [20.2]; P=0.005) and proportion of patients needing PCA for >24 h (23% vs. 36%; P=0.011). VATS patients who received ITD had a lower mean cumulative dose (mg) of PCA morphine (48.7 [58.1] vs. 64.6 [77.9]; P=0.029), a shorter total mean time (h) using PCA (30.2 [18.7] vs. 38.2 [21.8]; P=0.008) and fewer required PCA for >24 h (27% vs. 42%; P=0.040). There was no respiratory depression. Individual adverse events (pruritis, hallucinations, nightmares, headache, hypotension, urinary retention) were not significantly more common in either group, but when combined achieved significance with ITD (P=0.037). Conclusion. Addition of ITD to a multimodal analgesic regimen enhances analgesia following thoracic surgery with a low incidence of complications. References. 1. Meylan N, Elia N, Lysakowski C, et al. Benefit and risk of intrathecal morphine without local anaesthetic in patients undergoing major surgery: meta-analysis of randomized trials. Br J Anaesth 2009; 102: 156-167. O-56 Effects of one-lung ventilation on right ventricular function during thoracic surgery Isabelle Fonteyne, Stefaan Bouchez, Patrick Wouters, Laszlo Szegedi Department of Anaesthesiology, Ghent University Hospital, Gent, Belgium Introduction. There are no prospective randomized studies regarding the effects of one-lung ventilation (OLV) on right heart function. We have assessed with transoesophageal echocardiography (TOE), the heart function in general and particularly, with Tissue Doppler Imaging (TDI) at the tricuspid valve, the right heart function during two-lung ventilation (TLV) and OLV. Method. After IRB approval, written and informed consent, 10 ASA II-III patients scheduled for elective right thoracotomy were studied. An epidural catheter was inserted at mid-thoracic level, but not loaded. Induction and maintenance of general anaesthesia were standardized. Monitoring consisted of five lead ECG, pulse-oximeter, NIBP, radial artery catheter and a pulmonary artery catheter. Ventilator parameters with 50% oxygen in air were maintained constant. Lung separation was achieved with a left-sided double lumen tube. A TOE probe was inserted. The study was performed before surgery, in the supine position. After 15 minutes of TLV haemodynamic parameters were recorded, arterial and mixed venous blood gas samples were drawn, and TOE measurements made. The right lung was then excluded from ventilation. After 15 minutes of OLV, the

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measurements were repeated. Data were analysed with Student’s paired t-test [P<0.05, mean (SD)]. Results. The left ventricular ejection fraction [62.6 (6.1) vs. 56.0 (5.7)%] and shortening area decreased during OLV as compared to TLV. The right ventricular end-diastolic area increased, as well as the fractional area contraction. The tricuspid annular plane systolic excursion augmented (TAPSE) [1.9 (0.2) vs. 2.1 (0.3) cm] and the TDI at the tricuspid valve decreased [5.7 (1.5) vs. 4.9 (1.7)]. Only traces of tricuspid valve insufficiency were noted. Cardiac output, heart rate and mixed venous saturation remained constant. Discussion. We conclude that there is an adaptive, homeometric autoregulation of heart function with impaired left diastolic filling. Further studies are needed to assess the effects of longer OLV. O-57 Efficacy of intravenous paracetamol on postoperative analgesia after video-assisted thoracic surgery Alev Cınar1, Fatma Nur Kaya1, Belgin Yavascaoglu1, Suna 1 2 1 1 Goren , Sami Bayram , Elif Basagan-Mogol , Atilla Kaya 1

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Department of Anaesthesiology and Reanimation, Department 1 of Thoracic Surgery, Uludag University, School of Medicine, Bursa, Turkey Introduction. Video-assisted thoracic surgery (VATS), which is less invasive then conventional thoracotomy, causes less pain and better preservation of pulmonary function [1]. However, patients can still experience considerable pain following VATS. We aimed to assess the efficacy of intravenous paracetamol administration on postoperative analgesia after thoracoscopic surgery. Method. After ethic committee approval and informed consent, 40 patients with ASA I-II were randomly assigned to receive intravenous administration of either 1 g paracetamol or 100 ml saline before induction of anaesthesia and then every 6 h postoperatively for 24 h. Results. Postoperative pain scores were similar in the two groups.

Postop. morphine consumption 2h 4h 8h 12 h 24 h Time to first analgesic requirement (min) Time to first mobilization (h) Time to hospital discharge (h) Nausea/vomiting (n) Patient/nurse satisfaction = excellent (n) * P <0.05, ** P <0.01, *** P <0.001

Paracetamol Group(n=20)

Saline Group(n=20)

4.8r0.7* 6.1r0.9* 7.2r1.2*** 8.1r1.4*** 9.3r1.9*** 8.2±4.3* 4.4±2.1** 25.7±5.1** 3**/1** 11***/10**

12.1r2.3 17.3r3.6 24.2r5.2 32.3r8.9 37.1r9.7 4.7±2.5 6.9±2.5 31.7±6.8 14/12 0/0

Conclusion. The use of paracetamol reduced the postoperative morphine requirements and increased patient and nurse satisfaction with fewer side effects. This approach may also contribute to earlier postoperative mobilization after VATS. Reference. 1. Nagahiro I, Andou A, Aoe M, et al. Pulmonary function, postoperative pain, and serum cytokine level after lobectomy: a comparison of VATS and conventional procedure. Ann Thorac Surg 2001; 72: 362-365.

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Oral Session X – Postoperative Care & Organ Function O-58

O-59

Long-term survival and preoperative predictors of prolonged intensive care stay after major cardiac surgery

The comparison of dexmedetomidine and propofol for postoperative sedation in fast-track cardiac anaesthesia

Jose M Barrio, Fco. Javier Hortal, Javier Otero

Zeynep Pestilci Toz, Demet Sergin, Isik Alper, Seden Kocabas, Sezgin Ulukaya, Fatma Zekiye Askar

HGU. Gregorio Marañon, Madrid, Spain Introduction. The purpose of this study was to ascertain the long-term outcome after hospital discharge and to identify preoperative predictors of very long stay after major cardiac surgery. Method. We performed a retrospective study on a total of 3,055 consecutive patients who underwent major cardiac surgery to identify preoperative predictors of long stay after surgery. We excluded patients who died in the first 24 hours postoperatively (105; 3.4%) and heart transplant patients (112; 3.6%). A total of 2,838 patients were included in the study. A period exceeding 14 days, corresponding to the 90th percentile was selected as the threshold for a prolonged ICU stay. 291 (10%) patients who fulfilled this criterion were studied for survival analysis. Preoperative variables significantly associated with outcome were included in a multivariate logistic regression analysis. Kaplan-Meier estimates of long-term survival were determined. Results. Significant preoperative risk factors for prolonged stay in the ICU were: NYHA IV (OR: 1.84 IC 1.18-2.8), previous cardiac surgery, urgent cardiac surgery (OR: 2.13 IC 1.31-3.4), high additive EuroSCORE (OR: 32 IC 235-443), pulmonary disease (OR: 14 IC 1.02-1.97), preoperative creatinine >133 Pmol/L (1.5 mg/dl) (OR:1.99 IC 1.38-2.88), mixed coronary and valve surgery or surgery on ascending aorta) (OR: 181 IC 131250) and diabetes mellitus (OR: 1.42 IC 1.07-1.88). 122 of 291 (41.9%) patients died in hospital, 46 (15.8) died during the follow-up period. The 60 months survival for the study population is presented as a Kaplan-Meier survival plot.

Ege University Medical School Anaesthesiology Reanimation Department, Bornova, Izmir, Turkey

and

Introduction. The aim of this study was to compare the effects of dexmedetomidine and propofol on postoperative sedation, haemodynamic and respiratory parameters and satisfaction of patients undergoing coronary artery bypass grafting surgery. Method. Forty two patients (aged 40-75 years, ASA II-III, EF >40%) undergoing elective CABG were included in this prospective, double-blind, randomized clinical study. After anaesthesia induction with etomidate, fentanyl and rocuronium; maintenance of anaesthesia was provided by 1 mg kg-1 h-1 -1 -1 propofol, 0.5 μg kg h fentanyl and desflurane in 50% oxygen in air. Additional analgesia requirements were achieved with 1 μg/kg fentanyl boluses, and neuromuscular blocking agent requirements were achieved with 0.1-0.15 mg/kg rocuronium. Randomization to either dexmedetomidine group (n=21) or propofol group (n=21), via a random-number table, occurred in the operating room before sternal closure. After termination of fentanyl infusion, propofol was titrated to doses within the range -1 -1 of 0.2-0.7 mg kg h (propofol group) or propofol infusion was terminated and dexmedetomidine was started between the -1 -1 range of 0.2-0.7 μg kg h (dexmedetomidine group). Desflurane was discontinued after sternal closure. The postoperative sedation level was assessed using the Ramsey sedation scale and pain was assessed using a visual analogue scale (VAS). Patients were extubated after adequate clinical conditions were achieved. Postoperative haemodynamic parameters, pain, sedation level, respiratory parameters, chest drainage and patient satisfaction were assessed until extubation. Results. The times to weaning (65r42 vs. 104r70 min.) and extubation (207r57 vs. 249r68 min.) were shorter in the dexmedetomidine group compared with the propofol group (P<0.05), but ICU length of stay, analgesic requirement, chest drainage, haemodynamic parameters and side effects were found to be similar between groups. Conclusions. In patients undergoing coronary artery bypass grafting surgery, dexmedetomidine provides faster weaning and extubation conditions, but has no effect on postoperative sedation, haemodynamic and respiratory parameters and patient satisfaction when compared with propofol. O-60 A specialized anaesthesiological postanaesthetic care unit improves fast-track management in cardiac surgery Dirk Haentschel, Christoph Cech, Markus Scholz, Diana Mathioudakis, Jörg Seeburger, Jörg Ender

Conclusion. Most of prolonged UCI stay patients die soon after hospital discharge and long term survival is relatively poor. It is possible to identify preoperative risk factors for this complication after major cardiac surgery.

University Leipzig, Leipzig, Saxony, Germany Introduction. Fast-track treatment seems to be the global standard of care in cardiac anaesthesia [1]. Most fast track concepts imply treatment in the intensive care unit (ICU) and not in a specialized post anaesthetic care unit (PACU). In this study we compared fast track treatment in a PACU vs. treatment in the ICU.

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Method. After approval by the local ethics committee and written informed consent, patients undergoing elective cardiac surgery were included in this prospective, randomized study at the end of the operation when they were judged eligible for fasttrack-treatment by the anaesthesiologist and the surgeon. Subsequently they were randomized for postoperative treatment either in the ICU or PACU using the sealed envelope technique. Time to extubation (ET), length of stay (LOS) in PACU, ICU, intermediate care unit (IMC) and total hospital stay (LOSHOS) as well as postoperative complications were evaluated. Values are expressed as median and standard deviation. Results. In total 200 patients could be included in the study. For demographic data and type of operation see table 1. Time to extubation (ET) was 1.5 h in the PACU vs. 7.9 h in the ICU group (P<0.001). Length of stay in PACU was 3.3 h vs. 17.25 h in the ICU (P<0.001). Total hospital stay was 9.9 days in the PACU group vs. 10.7 d in the ICU group (P=0.13). The 30 days mortality was 0 in the PACU group vs. 3 in the ICU group. There were no significant differences in postoperative complications.

PACU n=100 64.5 ±11.8 64/36 2.46 ±2.0 63 ±11.5 2.0 ±0.8 43 25 32

P value

ICU n=100 66.0 ±10.8 78/22 2.34 ±1.6 60 ±11.2 2.0 ±0.7 47 29 24

Ravish Jeeji, Debbie Danitish, Lakshmi Srinivasan, Martyn Traves

0.61 0.042 0.99 0.3 0.65 n.s. n.s. n.s.

North Staffordshire University Hospital, Stoke- on -Trent, United Kingdom

Conclusion. The better physician to patient ratio in the PACU (3:1 vs. 12:1 in ICU) leads to significantly shorter extubation time and length of stay in ICU while maintaining patients’ safety. Reference. 1. Silbert BS, Myles PS. Is fast-track cardiac anesthesia now the global standard of care? Anesth Analg 2009; 108(3): 689691. O-61 The clinical value of routine chest radiographs in the first 24 hours after cardiac surgery 1

3

4

Martijn Tolsma , Anke Kroner , Cristy van den Hombergh , 2 2 2 Homme Dijkstra , Tom Rijpstra , Mohammed Bentala , Marcus 3 2 Schultz , Nardo van der Meer 1

O-62 Single dose gentamicin for gram negative prophylaxis for cardiac surgery: are we achieving adequate levels?

Table 1. Demographic data, performed operations Age (a) Gender (male/female) EuroSCORE Ejection fraction (%) NYHA CABG AV Replacement MV-Repair/Replacement

Results. Two hundred and fourteen successive patients were included. The majority of the patients underwent coronary arterial bypass grafting (60%), heart valve surgery (21%), or a combination of these (14%). In total 534 CXRs were performed (2.5 per patient). Abnormalities were found in 179 CXRs (33.5%). The overall therapeutic efficacy was 2.4%. For 32 (10%) of the 321 admission or drain removal CXRs, clinical indications were stated by the physician beforehand. Eighty-two abnormalities were found on these CXRs performed routinely, compared to 14 abnormalities on those clinically indicated. If these CXRs would not have been performed routinely, 68 abnormalities would have been missed. However, only 5 of them (7%) led to an intervention. Conclusion. Partial elimination of CXRs in the first 24 hours after cardiac surgery seems safe and cost-effective in the majority of patients. Only a limited number of identified patients benefit by the application of a routine CXR protocol.

2

Sint Antonius Hospital, Nieuwegein, Netherlands, Amphia 3 Hospital, Breda, Netherlands, Academic Medical Center, 4 Amsterdam, Netherlands, Academic Hospital Maastricht, Maastricht, Netherlands Introduction. Chest radiographs (CXRs) are obtained frequently in the intensive care unit (ICU). Whether these CXRs should be performed routinely or on clinical indication only is still debated. The aim of our study was to investigate whether (partial) elimination of routine CXRs is safe and cost-effective in a population of post-cardiothoracic surgery patients. Method. We prospectively included all consecutive cardiothoracic patients who underwent cardiac surgery during a two month period. 2 or 3 CXRs were performed in the first 24 hours of ICU stay. Following ICU admission and after drain removal, a clinical examination was performed before a CXR was obtained. All CXR abnormalities were noted and it was also noted whether they led to a change in therapy. For the admission CXR and the drain removal CXR, a comparison was made between all these CXRs performed routinely and those which were clinically indicated by the physician.

Introduction. Most cardiac units use gentamicin for gram negative prophylaxis. A single dose is preferred by most units. Our unit policy is to administer a second dose 12 hours after initial dosage to cover loss in the CPB circuit and large blood losses. There is no evidence to support this practice, even though this practice is backed by a local antimicrobial policy. Our study was to find whether the practice of giving a second dose is supported by the nomogram for gentamicin dosing (Urban and Craig nomogram) Method. Data was collected prospectively. Blood was taken for gentamicin levels before a second dose was administered. Results. Data from 129 patients was analysed. The majority of patients were males (68%) and underwent elective procedure (68%). Pre-op GFR ranged from 14 to 200 ml/min (estimated by Cockcroft - Gault equation). Measured trough level ranged from 0.4 to 17.4 mg/ml. All except one patient had trough levels within a normal range of 0.5 to 1 mg/ml, recommended for treatment of established infection. 39% of patients had a trough level of 2 mg/ml or more. As per present recommendation, a dose should be omitted if the level is 2 mg/ml or more (dosing interval more than 24 hours). A linear relationship existed between GFR and trough level, but not with length of cardiopulmonary bypass time. Trough level of 2.0 mg/ml or more was found in 85% of patients with GFR less than 60 ml/min. Conclusion. A single dose of 3 mg/kg gentamicin is adequate for 24 hour prophylaxis. A lower dosage may be adequate in patients with a low GFR Reference. 1. Zelenitsky SA, Ariano RE, Harding GK, et al. Antibiotic pharmacodynamics in surgical prophylaxis: an association between antibiotic concentrations and efficacy. Antimicrob Agents Chemother 2002; 46: 3026-3030.

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O-63 Perioperative inflammatory, coagulative and fibrinolytic state in patients having an operation for acute Type A aortic dissection 1

1

Domenico Paparella , Giuseppe Scrascia , Pietro Giorgio 1 1 1 Malvindi , Antonella Galeone , Giuseppe Visicchio , Andreas 1 1 2 2 Paramythiotis , Sara Freni , Maria Arbues , Giovanni Rubino , 2 1 Tommaso Fiore , Luigi de Luca Tupputi Schinosa 1

Division of Cardiac Surgery, Dipartimento dell'Emergenza e 2 Trapianti di Organi (D.E.T.O.), Division of Anesthesiology, Dipartimento dell'Emergenza e Trapianti di Organi (D.E.T.O.), University of Bari, Bari, Italy Introduction. Coagulopathy and organ dysfunction causing excessive bleeding are some of the reasons of higher morbidity and mortality observed in aortic dissection surgery. We prospectively evaluated the activation of inflammation, coagulation system and fibrinolysis in patients undergoing emergency surgery for aortic dissection. Method. Nineteen patients having an operation for acute Type A aortic dissection were enrolled. A group of 19 patients undergoing an elective CABG operation with cardiopulmonary bypass (CPB) served as a control group. Interleukin-6 (IL-6), prothrombin fragment 1.2 (PF 1.2) and plasmin-antiplasmin complex (PAP) were measured to verify the inflammatory state, thrombin generation and fibrinolysis activation respectively. Blood samples were obtained preoperatively (T0), 30 minutes after CPB initiation (T1), 15 minutes after aortic declamping (T2), 2 hours (T3), 24 hours (T4) and 5 days (T5) postoperatively. Results. The dissection group patients had longer CPB and cross-clamp time (P<0.0001) and longer ICU and hospital stay. They had a higher rate of blood transfusion and acute renal failure. Hospital mortality occurred in 5 patients (26.3%) and 1 patient (5.3%) in the dissection and CABG groups respectively. All markers were extremely activated preoperatively in the dissection group compared to control (IL-6: 135.01 ± 226.47 vs. 6.1 ± 5.7 ng/ml, P<0.0001. PF 1.2: 1007.78 ± 515.27 vs. 314.2 ± 356.1, P<0.0001. PAP: 1602.58 ± 1182.2 vs. 154.7 ± 253.4, P<0.0001). Such findings were confirmed postoperatively, at T2: (IL-6: 1325.99 ± 825.35 vs. 305.6 ± 494, P<0.0001. PF 1.2: 4937.72 ± 8826.94 vs. 862.5 ± 340,.1, P<0.0001. PAP: 3041.32 ± 2131.81 vs. 1189.5 ± 613.1, P=0.01). Discussion. Acute aortic dissection generates intense blood activation before the operation. This contributes, together with complex and prolonged surgery, for massive thrombin generation, fibrinolysis and IL-6 release during and after the operation. The observed increased incidence of morbidity and mortality in dissection patients may be influenced by such a haematologic state. O-64 Remote ischaemic preconditioning in patients undergoing off-pump coronary bypass grafting: prospective study and preliminary results Karol Krawczyk, Zbigniew Rybicki Wojskowy Instytut Medyczny, Warsaw, Poland Introduction. Ischaemic preconditioning has been analysed as an important cardioprotective phenomenon for many years. The same protection could also occur if the preconditioning ischaemic manoeuvre was applied distant from myocardium, making remote Ischaemic preconditioning (RIPC) beneficial for

patients undergoing cardiac surgery [1]. The aim of this study was to assess whether RIPC reduces myocardial injury in offpump coronary artery bypass surgery (OPCABG). Method. By December 2009 14 adults undergoing elective OPCABG were randomly assigned to either an RIPC group (n=8) or to a control group (n=6). RIPC was applied after induction of anaesthesia and consisted of three 5-min cycles of right upper limb ischaemia, induced by a manual cuff-inflator placed on the right upper arm and inflated to 200 mm Hg, with intervening reperfusion periods of 3 min when the cuff was deflated. Myocardial cell damage was assessed by serum troponin I (cTnI), creatine kinase MB (CKMB) and heart-type fatty acid-binding proteins (h-FAB) measured preoperatively and at 6, 12, 24 h postoperatively. Results. In the RIPC group h-FAB at 6 h after surgery (mean (SD) 9.75 (6.71) ng ml-1) was significantly lower (P<0.05) than in -1 the control group (18.38 (18.38) ng ml ). Also CKMB 6 h -1 postoperatively in the RIPC group (8.50 (3.02) U L ) was significantly lower (P<0.05) than in the control group (15.00 -1 (6.07) U L ). CKMB values at 12 and 24 h were lower (P=0.05). There was no significant difference between groups in postoperative cTnI and h-FAB values at 12 and 24 h after surgery. Discussion. We aim to provide clinical evidence, suggesting that the RIPC phenomenon represents a simple, inexpensive, easily applied cardioprotective method during OPCABG. Reference. 1. Cheung MM, Kharbanda RK, Konstantinov IE, et al. Randomized controlled trial of the effects of remote ischemic preconditioning on children undergoing cardiac surgery: first clinical application in humans. J Am Coll Cardiol 2006; 47: 2277-2282. O-65 The effect of administration of the flu vaccine on the immune response to venesection Niall McGonigle1, Marilyn Armstrong2, Ashling Brennan1, Peter 1 1 Elliott , William McBride 1

2

The Royal Victoria Hospital, Belfast, United Kingdom, The Queen's University of Belfast, Belfast, United Kingdom

Introduction. The ability of the immune system to regenerate immune potential cells after blood loss is important in both post surgical and trauma outcomes. Recently, there has been mass flu vaccination, and we wished to determine if this intervention modulates the immune response to blood loss in healthy volunteers. Method. Twenty healthy volunteers, age and sex matched, were randomized to receive the flu vaccine or placebo three days prior to venesection of 280 mL of blood. Analysis of whole blood, using flow cytometry, for peripheral blood mononuclear cells (PBMCs), antigen presenting dendritic cells (DCs) and lymphocytic T cells (T cells) was performed at the time points: A (immediately prior to vaccination/placebo), B (3 days later, immediately prior to venesection), C (4 days after venesection) and D (11 days after venesection). + Results. The numbers of circulating CD14 CD16 monocytes had a tendency to be reduced in the placebo patients at time C, which was not demonstrated in the vaccinated volunteers. The numbers of circulating antigen presenting DCs, fundamental to the innate immune response, and immunocompetent T cells were not altered as a result of flu vaccination. Conclusions. Administration of the flu vaccine prior to planned venesection does not alter immunocompetent cell numbers and therefore may not alter levels as the result of blood loss during surgery or trauma.

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Oral Session XI – Risk Factors & Outcome O-66

O-67

The preoperative State-Anxiety score of patients before cardiac surgery negatively correlates with 3rd postoperative day quality of recovery score

A physiological risk profile in comparison with the additive EuroSCORE for risk stratification in high risk cardiac surgery patients

Galina Leyvi, Olivia Nelson, Michelle Pasamba

Matthias Heringlake1, Jan Käbler1, Ingrid Anderson1, Christof 1 1 3 1 Garbers , Hermann Heinze , Leif Dibbelt , Julika Schön , Klaus1 4 2 Ulrich Berger , Frank Eberhardt , Thorsten Hanke

Montefiore MC/AECOM, Bronx, United States Introduction. Patients often experience anxiety before undergoing major surgery (state-anxiety). Some are personally susceptible to anxiety (trait-anxiety). It has been shown that a high anxiety score has been associated with an increased risk of nonfatal myocardial infarction or death after being diagnosed with coronary artery disease [1]. We examined the effects of preoperative anxiety on the recovery of cardiac surgery patients. Method. We assess preoperative anxiety by State-Trait Anxiety Inventory Scale (STAIS) and patients’ outcome by the Quality of Recovery Score (QoR-40). The QoR-40 is a valued measure of the quality of recovery after surgery and anaesthesia [2]. In cardiac surgery patients, a poor postoperative QoR-40 score predicted a poor quality of life for 3 months following surgery [3]. The STAIS questionnaire consists of 20 State-Anxiety (S-A) and 20 Trait-Anxiety (T-A) questions, which were administered to 20 patients in the OR holding area before cardiac surgery. The Quality of Recovery Score (QoR-40) consists of 40 questions which were administered on the 3rd post-operative day. Correlation was sought between S-A/T-A and QoR-40, as well as patients’ ages, duration of surgery, anaesthesia and CPB time. Results. The patients’ ages were 55 ± 14 years, duration of surgery 302 ± 62 min and cardiopulmonary bypass 121 ± 43 min. The score values were S-A: 39 ± 13.9, T-A: 33 ± 10.5, QoR-40: 159 ± 17.6. There was negative correlation between the S-AI and the QoR-40 score with r = - 0.55 (P=0.05). The other variables did not correlate with the QoR-40 score. Conclusion. The State-Anxiety score has a negative correlation with the 3rd postoperative day recovery score, which means that a higher preoperative anxiety level predicted poorer recovery in 3 days and maybe in 3 months. References. 1. Shibeshi WA, Young-Xu Y, Blatt CM. Anxiety worsens prognosis in patients with coronary artery disease. J Am Coll Cardiol 2007; 49: 2021-2027. 2. Myles PS, Weitkamp B, Jones K, et al. Validity and reliability of a postoperative quality of recovery score: the QoR-40. Brit J Anaesth 2000; 84: 11-15. 3. Myles PS, Viira D, Hunt JD. Quality of life at three years after cardiac surgery: relationship with preoperative status and quality of recovery. Anaesth Intensive Care 2006; 34: 176183.

1

Department of Anesthesiology, University of Lübeck, Lübeck, 2 Germany, Department of Cardiac and Thoracic Vascular 3 Surgery, University of Lübeck, Lübeck, Germany, Department of Clinical Chemistry, University of Lübeck, Lübeck, Germany, 4 Department of Cardiology, Hospital Köln-Kalk, Köln, Germany Introduction. The usefulness of the European system for cardiac operative risk evaluation (EuroSCORE) in high risk cardiac surgery patients (EuroSCORE >8) has been questioned. The present study was designed to determine if a physiological risk profile, combining N-terminal pro B-type natriuretic peptide (NTproBNP), high sensitive troponin-T (hsTNT), and cerebral oxygen saturation (ScO2) determined by Near-InfraredSpectroscopy, is suitable for risk stratification in a heterogeneous cohort of cardiac surgery patients in comparison with the EuroSCORE. Method. 984 consecutive patients (491 isolated and 177 combined CABG, and 316 NO-CABG patients) undergoing onpump cardiac surgery were studied. ScO2, hsTNT, and NTproBNP, and additive EuroSCORE, were determined preoperatively. Receiver operating characteristic (ROC) plot analyses were used to determine the cut-off values for 30-day mortality for hsTNT and ScO2. The physiological risk profile (PRP) was calculated as the sum of an established mortality cut-off value for NTproBNP (>1869 pg/mL), hsTNT (>30 pg/mL), and ScO2 (<54%) [1 point for each value in the adverse range times a factor of surgical priority (elective=1, urgent=2, emergency=3)]. ROC analyses were used to compare PRP and EuroSCORE for the whole group and according to different quartiles of the EuroSCORE (median 2, 5, 7, 10) Results. 30-day mortality was 3.4%. The Receiver-operating area-under-the-curve (AUC) for 30-day mortality of the EuroSCORE and the PRP in the whole group were 0.82 (0.79 to 0.84) and 0.84 (0.82 to 0.87) (P=n.s.). In the high risk quartile (EuroSCORE 9 – 19 (median 10) the AUC of the PRP (0.81 (0.74 to 0.86) was significantly (P=0.001) higher than the AUC of the EuroSCORE (0.62 (0.55 to 0.69). This was not the case in the lower EuroSCORE quartiles. Conclusions. A physiological risk profile using cut-off values for hsTNT, NTproBNP, and ScO2 is superior to the additive EuroSCORE for the prediction of 30-day mortality in high risk cardiac surgery patients with a EuroSCORE >8. O-68 Prediction of the occurrence of postoperative atrial fibrillation after on-pump cardiac surgery by postoperative BNP concentrations Giovanna Lurati-Buse, Jorge Kasper, Esther Seeberger, Regina Schumann, Manfred Seeberger, Miodrag Filipovic University Hospital of Basel, Basel, Switzerland Introduction. The aim was to explore the association between postoperative BNP concentrations and new atrial fibrillation (AF) after cardiac surgery.

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Method. Consecutive patients without any history of AF undergoing on-pump cardiac surgery at the University Hospital of Basel between April 2007 and November 2008 were included. BNP concentrations were measured on the first postoperative day at 6 a.m. The endpoint was the occurrence of new AF prompting the administration of amiodarone and/or ibutilid during the stay in the intensive care unit (ICU). We calculated a multivariable logistic regression with new AF as dependent variable and BNP concentration, age in 10 years intervals, ejection fraction (EF) and severe mitral valve disease as predefined independent variables. We calculated an additional model including BNP dichotomized at a cut-off value defined by ROC curve. Results. We included 815 patients; 608 (74.6%) were men and 409 (50.2%) underwent isolated CABG. The mean age was 67±11 years. EF was >50% in 504 patients (61.8%), 30-50% in 268 patients (33%), and <30% in 36 (4.4%) patients. A total of 178 (21.8%) patients presented with severe mitral valve disease. In 770 (94.5%) BNP concentrations were available, with a median BNP 448.4 pg/mL (interquartile range 285.8780.9). We registered the occurrence of 129 new AF during ICU stay. The unadjusted odds ratio (OR) for the association between BNP and new AF was 1.055 (95% confidence interval 1.026-1.083, P<0.001) per 100 pg/mL increase. After adjustment with age, preoperative EF, and severe mitral valve disease, the OR for the association between BNP and new AF was 1.033 (1.003-1.064, P=0.031) per 100 pg/mL increase. The unadjusted OR for the association between BNP t542 pg/mL and new AF was 2.044 (1.396-1.2.993, P<0.001). After adjustment, the OR for the association between BNP t542 pg/mL and new AF was 1.506 (0.996-2.276, P=0.052) Conclusions. BNP concentration at 6 a.m on the first postoperative day is an independent predictor of new atrial fibrillation requiring antiarrythmic therapy during ICU stay after on-pump cardiac surgery.

Discussion. Both PCI and CABG offer reasonable long-term survival in end-stage renal disease patients, nowadays. An increased need for coronary re-intervention observed in patients after PCI could possibly be attributed to incomplete interventions on diseased vessels during initial PCI. However, improved graftsurvival in comparison to stent-survival can also be responsible for the observed difference. Reference. 1. Nevis IF, Matthew A, Novick RJ, et al. Optimal method of coronary revascularization in patients receiving dialysis: systematic review. Clin J Am Soc Nephrol. 2009; 4: 369-378. O-70 Preoperative cardiac troponin I to assess mid-term risks of coronary bypass operations in patients with recent myocardial infarction

O-69 Long-term survival and need for coronary re-intervention in end-stage renal disease patients treated with PCI in comparison to CABG Katarzyna Klajbor1, Romuald Lango1, Rafal Pawlaczyk2, Maciej 1 2 2 Kowalik , Piotr Siondalski , Jan Rogowski 1

coronary re-intervention was 1069 days (SD: 923) after PCI and 2128 days (SD: 1075) after CABG (P<0.001). Re-interventionfree survival is presented in Fig.1. 20% of patients underwent renal transplantation during the follow-up.

Domenico Paparella1, Giuseppe Scrascia1, Maria Arbues2, 2 1 1 Giovanni Rubino , Vito Margari , Manuela Conte , Luigi de Luca 1 Tupputi Schinosa 1

Division of Cardiac Surgery, University of Bari, Bari, Italy

2

Department of Anesthesia,

2

Department of Cardiac Anaesthesiology, Department of Cardiac and Vascular Surgery, Medical University of Gdansk, Gdansk, Poland Introduction. End-stage renal disease in patients with ischaemic heart disease represents an import risk factor for accelerated progress of coronary atherosclerosis. In end-stage renal disease patients after percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) an increased rate of coronary re-intervention, due to either graft or stent dysfunction, or de-novo narrowing of a previously patent artery is observed. Despite higher peri-procedural mortality in CABG patients, lack of difference in long-term mortality between PCI and CABG was reported [1]. Method. We retrospectively analysed files of 184 patients with end-stage renal disease, who were submitted to PCI or CABG between 1999 and 2009. End-points of our study were mortality and coronary re-intervention. Results. 74% of patients were treated with haemodialysis and 26% with peritoneal dialysis. Mean age of patients was 62 years (range: 22-81; SD: 11.2). 116 patients (63%) were submitted to PCI and 68 (37%) underwent CABG. Long-term survival in the PCI group was 79% which was not significantly different from 84% observed in the CABG group (P=0.3). Mean time until

Introduction. The optimal timing for coronary artery bypass grafting (CABG) in patients with recent acute myocardial infarction (AMI) is unclear. Cardiac troponin I (cTnI) is a widely accepted biomarker of myocardial damage. The objective of this study was to determine whether preoperative cTnI values may be used to determine risk stratification for CABG operations in patients with recent AMI. Method. One hundred and eighty four patients who suffered a recent AMI (onset <21 days) undergoing non-urgent CABG operations were evaluated. They were divided in two groups according to their preoperative cTnI values: cTnI ”0.15 ng/mL Group (117 patients) and cTnI >0.15 ng/mL Group (67 patients). A logistic regression model was used to assess the associations between study variables and events. Time from AMI to operation was evaluated in order to define preoperative cTnI variation. Results. cTnI values tended to decrease when the interval between AMI and operation increased. Preoperative cTnI values were significantly associated with a higher incidence of major postoperative complications (low cardiac output syndrome, IABP necessity, mechanical ventilation >72 hours, acute renal failure, in-hospital mortality). Perioperative myocardial damage was more pronounced in cTnI >0.15 ng/mL Group patients. Multivariate analysis revealed cTnI >0.15 ng/mL as an

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independent predictor for six-month mortality (Odds Ratio=3.7, P=0.043). Conclusions. Preoperative cTnI >0.15 ng/mL in patients with a recent AMI undergoing CABG is associated with higher postoperative myocardial damage and is a strong determinant of postoperative morbidity and mortality within the six-month period.

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O-72 Postoperative cardiac risk in patients with coronary stents: comparison between bare metal stents and drug eluting stents Jose Molina, Itxaso Merino, Guillermina Fita, Adriana Hervías, Irene Rovira

O-71 Hospital Clinic, Barcelona, Spain Is fixed, moderately elevated pulmonary vascular resistance still an independent risk factor in heart transplantation? Åsa Charlott Haraldsson, Hans Lidén, Oscar Kolsrud, Lars Wilund Sahlgrenska University Hosptal, Gothenburg, Sweden Introduction. Pulmonary vascular resistance (PVR) >2.5 Wood units (WU), as one of the parameters defining primary or secondary pulmonary hypertension (PH), is an established risk factor for mortality in heart transplantation due to the subsequent, right heart failure of the graft that may ensue. Therefore, a test of potential reversibility of PH with intravenous or inhaled vasodilators is warranted in the evaluation of candidates. Elevated PVR, non-responsive to dilation, is considered as fixed. Method. Heart transplant recipients at our institution 1988-2007 (n=362) were reviewed. Right heart catheterization, with dilatation, was performed (n=137) and this subset of patients were included into two groups with respect to pre-transplant, dilated PVR: <3 WU (n=114) and >3 WU (n=23). One-year survival after heart transplantation was reviewed, using Coxregression analysis, also with respect to the following variables: pre-transplant dilated PVR, recipient age and sex, diagnosis, CMV-status, ischaemic time, donor sex and age. Results. The mean PVR in the group non-responsive to dilatation was 3.7± 0.7 WU and in the group responsive to dilatation, 2.0±0.6. There was no significant difference in 1-year survival between groups with respect to pre-transplant dilated PVR. The one parameter investigated in this study found to be an independent risk factor for increased 1-year mortality was CMV-status recipient-donor mismatch (P=0.034). Conclusions. This retrospective review of heart transplant recipients with pre-transplant, moderately elevated PVR, responsive or non-responsive to dilation to <3 WU, revealed no difference in 1-year survival, CMV-mismatch appears to be a parameter of greater importance. The result of this study warrants further investigation of the cut-of level of elevated PVR that represents an increased risk in the concept of heart transplantation, especially with regard to prevailing modern therapeutic approaches to the treatment of graft right heart failure.

Introduction. Patients with bare metal coronary stents (BMS) or drug eluting coronary stents (DES) constitute a high risk population for developing postoperative cardiac morbidity and mortality. Moreover, the perioperative withdrawal of dual antiplatelet drug therapy and a short period of time from stent placement to surgery (less than 1 month for BMS and less than 12 months for DES) are two major risk factors for suffering cardiac adverse events. Method. The aim of this prospective observational study was to assess outcome differences between patients with BMS and DES undergoing surgery. The primary endpoints included major adverse cardiac events (death, acute coronary syndrome (ACS) and stent thrombosis) and bleeding events during the hospitalization and during 3 months follow up. Information about the discontinuation of antiplatelet drug therapy and the interval of time from stent placement to surgery, were analysed as secondary endpoints. Results. A total of 126 patients (94 with BMS and 32 with DES) were included in this study from March 2007 to September 2009. Bleeding ACS events BMS DES

5.31% 6.25%

Death

10.90% 6.09% 6.80% 0%

Stent thrombosis 0% 0%

Discontinued Interval time < antiplatelet recommended therapy *10.60% 9.5% *40.625% 3.12%

There were no statistical differences between BMS and DES in any of the studied variables, except for timing of surgery after stent placement. We found a significantly higher number of cases in DES group, in which surgery was performed before the recommended interval of time (12 months after stent placement) (P<0.05). Conclusions. In our study there were no differences in postoperative cardiac complications between patients with BMS and DES, even although the number of cases in which surgery was not postponed the recommended time interval, was significantly higher in the DES group. The higher rate of maintenance of antiplatelet drug therapy could have been a protective factor in the DES group . O-73 Factors associated with postoperative infection after paediatric cardiac surgery Andrea Székely1, Tamás Breuer2, Roland Tóth2, Attila Tóth2, 1 2 2 Daniel Lex , Erzsébet Sápi , András Szatmári , Zsuzsanna 1 Cserép 1

Semmelweis University, Department of Anesthesiology, 2 Budapest, Hungary, Gottsegen György Hungarian Institute of Cardiology Pediatric Heart Center, Budapest, Hungary Introduction. As survival has been improved after paediatric cardiac surgery, focus has shifted to reducing the morbidity. The aim of our study was to determine the prevalence, characteristics, and risk factors for infections in this population.

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Method. We have retrospectively analysed the data of 1,665 operated paediatric patients from 2004 to 2008. Patient demographics, co-morbidities, details of surgery, transfusion requirement, inotropic infusions, laboratory parameters and positive organism cultures during hospital stay were recorded. End points were occurrence of positive organism cultures and infection. Results. From the study population 276 (16.6%) patients had positive organism cultures and 260 patients (12.6%) had infection. Positive bloodstream, bronchial and vascular catheter associated cultures were obtained in 123 (7.4%), 46 (2.8%) and 154 (9.2%) patients, respectively. Table 1. shows the multivariable logistic regression model (C-index 0.87)

Preoperative Infection Preoperative positive nose-throat culture Pulmonary hypertension Operation time (min) Red blood cells intraoperative (ml/kg) Fresh frozen plasma intraoperative (ml/kg) Postoperative reoperation Positive culture plus mechanical ventilation Insulin Postop blood glucose maximum (mmol/L) Postop blood glucose mean (mmol/L) Base excess (mmol/L)

AOR 2.26 2.05 1.87 1.00 1.01 0.99

95.0% C.I. 1.17 4.36 1.14 3.68 1.16 3.01 1.00 1.00 1.00 1.01 0.98 1.00

P 0.015 0.016 0.010 0.001 0.022 0.009

4.80 4.73

2.64 2.83

8.75 7.90

<0.001 <0.001

1.72 1.16 0.75 1.08

1.02 1.04 0.62 1.00

2.91 1.30 0.92 1.15

0.043 0.010 0.005 0.041

AOR, adjusted odds ratio

Conclusions. The main factors associated with postoperative infection were more complex surgery, more transfusion and several laboratory derangements.

Oral Session XII – Effects of Opioids & Neural Blockade O-74 Influence of opioid selection and dosage on postoperative pain and morphine consumption after CABG surgery Jörg Fechner, Harald Ihmsen, Andre Wilkerling, Sebastian Kreißel, Steffi Kröber, Joachim Schmidt, Christian Jeleazcov University of Erlangen Nuremberg, Anesthesiology, Erlangen, Germany

Department

of

Introduction. The selection of remifentanil for intraoperative analgesia may contribute to postoperative pain [1]. Increased postoperative pain may increase the incidence of chronic postoperative pain [2]. The relevance of these findings in surgical patients is less well understood [3]. Therefore we studied the effect of two different intraoperative concentrations of remifentanil and sufentanil on postoperative pain and postoperative opioid consumption in patients undergoing CABG surgery. Method. Fifty six male patients (age 59±8 yrs) scheduled for first time CABG surgery were randomized to receive a TIVA with propofol and a target-controlled infusion with either remifentanil -1 -1 4 ng˜ml (group RL) or 8 ng˜ml (group RH) plasma -1 concentration, or with sufentanil 0.4 ng˜ml (group SL) or 0.8 -1 ng˜ml (group SH) plasma concentration from skin incision to skin closure. Postoperative morphine requirement were assessed, and pain rating (NRS: 0-10) at rest and during movement, and area of hyperalgesia were monitored. The data was analysed by ANOVA. Results. Treatment significantly influenced postoperative pain at day 1, and postoperative morphine consumption (table 1). Morphine consumption was lowest in group SL (P=0.006 compared to RL, P=0.06 compared to SH, Turkey test). Table 1. Morphine requirement (mean±SD) and pain rating (median and range) 0.47±0.16

RH (n=14) 0.38±0.12

0.30±0.09

SH (n=12) 0.43±0.13

0.008

3 (0 - 6) 4 (0 - 6)

2 (0 - 6) 4 (0 - 8)

0 (0 - 3) 2 (0 - 8)

2 (0 - 4) 4 (0 - 8)

0.032 0.037

RL (n=16) Morphine (μg kg-1min-1) NRS rest, day 1 NRS mov, day 1

SL (n=14)

P

Discussion. Intraoperative opioid selection and dosing significantly influences postoperative morphine consumption and pain after CABG surgery.

References. 1. Cabañero D, Celerier E, García-Nogales P, et al. The pronociceptive effects of remifentanil or surgical injury in mice are associated with a decrease in delta-opioid receptor mRNA levels. Pain 2009; 141: 88-96. 2. Fassoulaki A, Melemeni A, Staikou C, et al. Acute postoperative pain predicts chronic pain and long-term analgesic requirements after breast surgery for cancer. Acta Anaesthesiol Belg 2008; 59: 241-248. 3. Fishbain DA, Cole B, Lewis JE, et al. Do opioids induce hyperalgesia in humans? An evidence-based structured review. Pain Med 2009; 10: 829-839. O-75 A survey of post-sternotomy chronic pain following cardiac surgery Alan Ashworth, Coralie Carle, Andrew Roscoe North West Heart Centre, Manchester, United Kingdom Introduction. Persistent chest wall pain following cardiac surgery, termed Post CABG Pain Syndrome (PCPS) in 1989 [1], has an incidence of up to 56% and is an important postoperative complication. Our patients are not forewarned for PCPS. We undertook a survey of 100 CABG patients in order to determine the incidence of PCPS in our population. Method. We obtained local ethics committee approval for this structured questionnaire. One hundred consecutive CABG patients were contacted by telephone eight to ten months after their operation. PCPS was defined using previously published criteria [1]. The pain was qualified in terms of its site, nature, severity, neuropathic component, need for analgesics and effect on sleep and activities of daily living. The data was analysed using Fisher’s exact test with Bonferroni correction for multiple comparisons and unpaired Student’s t-test. A separate questionnaire established the cardiac surgeons’ perceived incidence of PCPS. Results. Completed data sets were available for 79 patients. 46% of patients met the criteria for a diagnosis of PCPS. Analysis revealed statistically significant higher mean pain scores on ICU (P=0.012), the ward (P=0.046) and on discharge (P=0.024) in the patients with PCPS. Subgroup analysis of other previously reported risk factors for PCPS failed to reach statistical significance. The cardiac surgeons estimated the incidence of PCPS to be 0.01 - 5%.

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Discussion. This study reveals a high incidence (46%) of PCPS in our population. Our data shows that increased post-operative pain is a risk factor for developing PCPS. Limitations of this study include selection bias and small sample size. We conclude that PCPS is a significant complication for which patients should be forewarned. We intend to further investigate the link between increased post-operative pain and PCPS. Reference. 1. Mailis A, Chan J, Basinski A, et al. Chest wall pain after aortocoronary bypass using internal mammary artery graft: a new syndrome? Heart Lung 1989; 18: 553-558.

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O-77 High thoracic epidural anaesthesia does not contribute to development of pathological vasodilatation after extracorporeal circulation Jan Kunstyr1, Ferdinand Polak1, Dagmar Lincova2, Michal Lips1, 1 1 1 Michal Porizka , Milos Dobias , Jaroslav Lindner , Martin 1 Stritesky 1

2

General University Hospital, Institute of Pharmacology, 1st Medical Faculty, Charles University, Prague, Czech Republic

O-76 A survey of chronic leg pain following saphenous vein harvesting for coronary artery bypass grafting Coralie Carle, Alan Ashworth, Andrew Roscoe North West Heart Centre, Manchester, United Kingdom Introduction. Chronic pain relating to saphenous vein harvesting for CABG is an important post-operative complication with a reported prevalence of 27% [1]. We undertook a survey of 100 CABG patients in order to determine the incidence of chronic leg pain relating to saphenous vein harvesting in our population. Method. We obtained local ethics committee approval for this structured questionnaire. One hundred consecutive CABG patients, who had undergone open saphenous vein harvesting, were contacted by telephone eight to ten months after their operation. Chronic leg pain was defined as pain arising postoperatively in the location of the surgery and persisting for more than three months. The pain was qualified in terms of its site, nature, severity, neuropathic component, need for analgesics and effect on sleep and activities of daily living. The data was analysed using Fisher’s Exact Test with Bonferroni correction for multiple comparisons and unpaired Student’s ttest. Results. Completed data sets were available for 79 patients. 29% of patients fulfilled the criteria for chronic leg pain. Analysis of previously reported risk factors for chronic pain failed to reach statistical significance. Discussion. This study reveals a high incidence (29%) of chronic leg pain after open saphenous vein harvesting in our population. This is consistent with the literature [1]. Endoscopic saphenous vein harvesting has been shown to reduce postoperative discomfort and has now been adopted by our institution. Limitations of this study include selection bias and small sample size. We conclude that chronic leg pain is a significant complication for which patients should be forewarned. We will repeat this study to determine the effect of changing to endoscopic saphenous vein harvesting on the incidence of chronic leg pain in our population. Reference. 1. Bruce J, Drury N, Poobalan AS, et al. The prevalence of chronic chest and leg pain following cardiac surgery: a historical cohort study. Pain 2003; 104: 265-273.

Introduction. It has been suggested that sympathetic blockade in patients by high thoracic epidural anaesthesia (HTEA) may contribute to the development of pathological vasodilatation after extracorporeal circulation (ECC). Especially patients with low ejection fraction (EF) on ACEI therapy should be more susceptible to this clinical situation. Method. After having signed an informed consent, twenty patients for cardiac surgery and on ACEI therapy with EF less than 35%, were randomly allocated either to the study group or to the control group. The 10 study group patients received HTEA and general anaesthesia. The 10 control group patients received balanced anaesthesia alone. A Swan-Ganz catheter was introduced in each patient. Demographic and perioperative haemodynamic data, vasopressin and cortisol plasma levels, use of inotropes, noradrenaline and terlipressin, mortality, length of stay and complications were recorded. The results were statistically analysed using Fisher’s exact test in four-field tables, Kolmogorov-Smirnov’s test, Mann-Whitney U test and repeated measures ANOVA respectively. Results. Apart from hormone levels, there were no statistically significant differences between the groups in any recorded variables. Vasopressin level was significantly lower in the study group patients before induction of anaesthesia and 24 hours after the surgery, and it was significantly higher in the same patients after aortic declamping. Cortisol level was significantly lower in the study group patients after aortic declamping and 24 hours after the surgery. One patient died in each group. Conclusions. Although previous findings showing lower cortisol and higher vasopressin levels during ECC in HTEA patients were confirmed, this study has also shown that combined HTEA + general anaesthesia does not contribute to a higher frequency of clinically relevant vasodilatory shock during and after ECC. Reference. 1. Treschan TA, Peters J. The vasopressin system: physiology and clinical strategies. Anesthesiology 2006, 105: 599-612. O-78 High thoracic epidural analgesia or the level of sufentanil has no impact on cardiac recovery time parameters Anne E Vester, Erik Sloth, Christian Lindskov, Carl-Johan Jakobsen Aarhus University Hospital, Skejby, Aarhus, Denmark Introduction. In order to use ICU time efficiently many departments are investigating and running different “Fast-track” regimes. One of the standard assumptions is that early extubation may lead to faster discharge, thus different anaesthetic protocols have been evaluated. Method. We examined ICU recovery of sixty patients from a cardiac protection study, randomized to four different anaesthetic regimes (± high thoracic epidural analgesia (HTEA) and ± sevoflurane). Major parameters were ventilation time, and eligible and actual discharge from ICU. The eligible time to

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discharge was based on a previous published method, IDS4 [1]. Extubation was done by the nurses based on objective criteria. Results. As indicated by the table neither HTEA nor moderate doses of sufentanil had any impact on any median time parameters. Multiple regression analyses further revealed that, beside the above, neither age, EuroSCORE nor the use of sevoflurane had any impact on ventilation time. The IDS4 score [1] revealed that HTEA patients postoperatively had lower scores for pain and haemodynamic parameters and higher scores for sedation and nausea. All patients sufentanil level (μg kg-1 h-1)

Ventilation (h)

0.00 0.01 - 1.00 1.01 - 3.00 All patients HTEA or Control Control HTEA

Discharge time ICU (h) Actual

Days in Hospital

Eligible

4.5 4.4 4.7

19.1 8.3 8.1

21.8 21.9 22.3

6.1 5.1 5.7

4.6 4.5

8.1 9.1

21.6 22.3

5.9 5.1

Discussion. The primary findings are as in a previous study, that the difference between eligible and actual discharge from ICU is rather long. Further, our data shows that neither anaesthetic method nor the level of sufentanil has any impact on ventilation time and LOS in ICU. Thus those parameters are guided by other factors. The ventilation time is thus defined by our criteria for extubation, but as scoring was not done before extubation, our data cannot reveal that. LOS in ICU is most likely guided by practical and logistic factors. Reference. 1. Jakobsen C-J, Vestergaard AL, Nygaard M, et al. An ICU discharge model; for research and logistic purpose. TOCTS 2009; 2: 12-17. O-79 Neuraxial blockade in patients undergoing minimally invasive direct coronary artery bypass surgery Leszek Machej1, Dariusz Szurlej1, Andrzej Weglarzy1, Lukasz 2 2 Krzych , Andrzej Bochenek 1

2

Dept of Cardiac Anaesthesia & Intensive Care, Dept. of Cardiac Surgery, Silesian Medical University, Katowice, Poland Introduction. The aim of the study was to assess the total spinal anaesthesia (TSA) effects on the perioperative use of opiates and time of artificial ventilation in patients undergoing minimally invasive direct coronary artery bypass grafting (MIDCAB). Method. The retrospective cohort study was performed in the university teaching hospital. Twenty-four consecutive patients for MIDCAB surgery were divided into TSA group (n=12) receiving an intrathecal injection of 20 mg heavy spinal bupivacaine with 0.5 mg morphine and the control group (n=12) receiving standard high dose fentanyl anaesthesia. Results. The intraoperative dose of fentanyl in TSA group was 0.29 ± 0.01 mg and 2.98 ± 0.66 mg in the control group (P<0.005). All patients were extubated in the ITU settings. Extubation time was 4.09 ± 1.04 hours in the TSA patients and 7.60 ± 2.75 hours in the control group (P<0.005). Morphine requirements in 24 hours after surgery were 0.67 ± 1.61 mg in the TSA group and 8.50 ± 6.26 mg in the control group (P<0.005). No differences in surgical procedure time, postoperative blood loss and fluid requirements were observed. Discussion. The neuraxial blockade can be considered as a safe and effective method of anaesthesia and perioperative analgesia in MIDCAB surgery. The most appropriate dose of subarachnoid medicaments should be evaluated in further prospective studies.

References. 1. Zisman E, Shenderey A, Ammar R, et al. The effects of intrathecal morphine on patients undergoing minimally invasive direct coronary artery bypass surgery. J Cardiothorac Vasc Anesth 2005; 19: 40-43. 2. Falcucci O. Central neuraxial analgesia in cardiac surgery. Mt Sinai J Med 2002; 69: 45-50. O-80 Pretreatment with stellate ganglion blockade ischaemia reduces infarct size in rat hearts Nebahat Bulut1, Ersoz Gonca2, 2 1 Bozdogan , Kazim Karaaslan

Hasan

1

before 1

Kocoglu ,

Omer

2

Medical Faculty, Dept. of Anesthesiology, Faculty of Science, Dept. of Biology, Abant Izzet Baysal University, Bolu, Turkey Introduction. The aim of this study was to investigate the role of stellate ganglion blockade (SGB) as cardio-protection against ischaemia reperfusion injury, and to compare its effects with ischaemic preconditioning. Method. Twenty-one Sprague–Dawley male rats were used in the study after approval from the animal care and use committee of the university. Rats were randomly divided into three groups. In all groups, cardiac ischaemia was achieved for 30 minutes after induction by ligating the left coronary artery followed by a reperfusion period of 120 minutes. Percutaneous ganglion blockade was applied to ‘SGB’ group rats before ischaemia was applied. ‘P’ group rats were subject to ischaemia and then reperfusion periods for 5 minutes before long lasting ischaemia was applied. The control group rats were injected with normal saline before the ischaemia-reperfusion period. The ratio of the area at risk to the total area were compared together with the occurrence of arrhythmia between groups. Results. The score for arrhythmia was significantly lower in both the preconditioning (1.6±0.4) and SGB (1.4±0.4) groups compared to control (3±0.2) group measured in 30 min of ligation, and the duration of arrhythmia was significantly shorter in the preconditioning group (P<0.05). During ischaemia, the incidence of arrhythmia was lowest in the SGB group, but during the reperfusion period the incidence of arrhythmia was highest in the SGB group. The ratio of the area at risk to the total area was similar in all groups, and the infarct size was measured to be significantly smaller in the preconditioning group and SGB group compared to controls (P<0.05)(Table 1). Table 1. The areas under risk and infarct areas (mm2). Group

Stellate Blockade (n=7) Preconditioning (n=7) Control (n=7)

Area at risk/Total area

Infarct size /Area at Risk

53±7 57±3 51±2

40±8* 29±4* 59±5

Conclusions. Left stellate ganglion blockade prior to ischaemiareperfusion procedure leads to lower arrhythmia scores, and reduces infarct size in Langendorff-perfused rat hearts. O-81 Variation in peroperative inotropic therapy in cardiac surgery in Denmark Dorthe Viemose Nielsen, Carl-Johan Jakobsen Department of Anaesthesia and Intensive Care, Aarhus University Hospital, Skejby, Aarhus, Denmark

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Introduction. Peroperative pharmacologic therapy is a critical step in managing low output syndrome after cardiopulmonary bypass. However, no consensus exists regarding choice of inotropes to guide best practice. The aim of the present study was to describe the use of inotropic therapy in cardiac surgery in Denmark, and to relate patient and procedure related factors to choice of inotropic therapy. Method. A retrospective study of 3,828 consecutive patients undergoing CABG or combined valve/CABG surgery between January 2007 and December 2008 using a computerized database from 3 University Hospitals in Denmark, was carried out. Results. The figure demonstrates the marked unadjusted variation in the rate of inotropic use among experienced anaesthesiologists across the 3 heart centres. Predictors of inotrope use will be presented. However the greatest impact was the name of the anaesthesiologist.

Discussion. Based on this study there does not appear to be a standard approach to inotropic use even after adjustment for patient and operation characteristics.

Best Oral Session O-82 Blood pressure restoration with norepinephrine improves renal function and oxygenation in post-cardiac surgery patients with vasodilatory shock and acute kidney injury

further increase in NE, to a MAP of 90 mmHg, does not further improve RBF, GFR or urine flow. References. 1. Bellomo R, Wan L, May C. Vasoactive drugs and acute kidney injury. Crit Care Med 2008; 36(4 Suppl): S179-186. O-83

Bengt Redfors, Gudrun Bragadottir, Kristina Swärd, Johan Sellgren, Sven-Erik Ricksten The Sahlgrenska Academy, Gothenburg, Sweden

University

of

Gothenburg,

Introduction. The use of norepinephrine (NE) in volumeresuscitated vasodilatory shock and acute kidney injury (AKI) remains controversial [1]. There are no data on the effects of NE-induced variations in MAP on renal blood flow (RBF), glomerular filtration rate (GFR), renal oxygen consumption (RVO2) or renal oxygen demand/supply (i.e. renal oxygen extraction, RO2Ex), in patients with AKI and vasodilatory shock. Method. Twelve post-cardiac surgery patients with NEdependent, vasodilatory shock and a serum-creatinine increase >50% were included. NE dose was randomly titrated to target MAP of 60, 75 and 90 mmHg for one hour periods. RBF was measured by retrograde thermodilution of the left renal vein. Arterial and renal vein oxygen content was measured for assessment of RVO2 and RO2Ex. GFR was calculated as the product of renal Cr-EDTA extraction and renal plasma flow. Systemic haemodynamics were measured by a PAC. ANOVA for repeated measurements were followed by Fisher’s PLSD tests, comparing data at 60 and 90 mmHg with those at 75 mmHg. Data are presented as means ± SEM. Results. MAP (mmHg) CI (L·min-1·m-2) RBF (ml·min-1) RVR (units) GFR (ml·min-1) RVO2 (ml·min-1) RO2Ex (%) UF (ml·min-1)

60 mmHg 60.0±0.8*** 2.5±0.1** 442±47 0.13±0.01* 25.3±3.1** 10.4±1.2 17.5±0.9* 1.9±0.3***

75 mmHg 73.5±0.7 2.8±0.2 477±54 0.15±0.01 32.3±3.6 11.0±1.1 16.3±0.9 4.0±0.5

90 mmHg 90.1±1.2*** 3.0±0.2* 442±38 0.18±0.02*** 31.6±3.3 10.8±0.9 16.9±0.9 4.4±0.5

post 75 74.7±0.7 2.8±0.1 456±38 0.15±0.01 30.0±2.2 10.7±1.1 16.6±1.0 4.1±0.6

*P<0.05,**P<0.01, ***P<0.001 vs. 75 mmHg; units = mmHg·ml-1·min-1.

Conclusion. When MAP is restored from 60 to 75 mmHg in patients with AKI and post-cardiac surgery vasodilatory shock, NE increases GFR (25%), urine flow and renal oxygenation. A

Renal blood flow, glomerular filtration rate and renal oxygenation in early acute kidney injury after cardiac surgery Bengt Redfors, Gudrun Bragadottir, Kristina Swärd, Johan Sellgren, Sven-Erik Ricksten The Sahlgrenska Academy, Gothenburg, Sweden

University

of

Gothenburg,

Introduction. Acute kidney injury (AKI) is a frequent complication after cardiac surgery. It is often considered to be due to renal ischaemia [1]. The decrease in glomerular filtration rate (GFR) in AKI should lead to a decrease in renal reabsorptive workload and thereby a decrease in renal oxygen consumption (RVO2). However, there are no data on renal perfusion, filtration and oxygenation in early AKI after cardiac surgery. Method. Twelve patients with AKI and 37 with normal renal function (control) were included. Renal blood flow (RBF) was measured by two independent techniques, retrograde thermodilution of the left renal vein and infusion clearance of PAH. Arterial and renal vein oxygen content were measured for assessments of RVO2 and renal oxygen demand/supply (=renal oxygen extraction, RO2Ex). GFR was calculated as the product of renal Cr-EDTA extraction and renal plasma flow. Sodium + reabsorption (Na -reab) was defined as the difference between filtered and excreted sodium. Systemic haemodynamics were measured by a PAC. Data are presented as means ± SEM and differences tested by Student’s t-test. Results. MAP (mmHg) CI (L·min-1·m-2) SVRI (dyn·s·cm-5·m-2) RBFTD (ml·min-1) RVR (mmHg·ml-1·min-1) GFR (ml·min-1) Na+-reab (mmol·min-1) RVO2 (ml·min-1) RO2Ex -1 Urine flow (ml·min ) O2/Na+-reab (ml·mmol-1)

Control n=37 73.9 r 1.15 2.6 r 0.08 2084 r 71 758 r 40 0.10 r 0.005 74.7 r 4.7 9.7 r 0.7 10.5 r 0.6 0.097 r 0.004 3.73 r 0.39 1.11 ± 0.04

AKI n=12 73.5 r 0.68 2.8 r 0.16 1847 r 88 477 r 54 0.15 r 0.015 32.3 r 3.6 4.0 r 0.44 11.0 r 1.1 0.163 r 0.009 4.04 r 0.48 2.90 ± 0.21

P Value ns ns 0.048 <0.001 0.010 <0.001 <0.001 ns <0.001 ns <0.001

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Conclusion. Renal oxygen supply/demand relationship is severely impaired in AKI after cardiac surgery, despite the decrease in GFR and tubular workload. The results indicate that + this is due to a combination of Na - reabsorption at high oxygen cost and renal vasoconstriction Reference. 1. Rosenberger C, Rosen S, Heyman SN. Renal parenchymal oxygenation and hypoxia adaption in acute kidney injury. Clin Exp Pharmacol Physiol 2006; 33: 980-988.

O-85 Standard immune monitoring versus CD64 quantification for early detection of infection after cardiac surgery Sabrina Righi, Luisa Santambrogio, Anna Monsagrati, Arianna Gatti, Bruno Brando, Giorgio Musazzi, Germano Di Credico, Danilo Radrizzani Civil Hospital of Legnano, Legnano, Italy

O-84 Simultaneous anaesthetic and remote preconditioning during cardiac surgery – a clinical strategy? 1

1

1

Parthee Karuppasamy , Sanjay Chaubey , Jatin Desai , Lindsay 1 2 1 John , Mike Marber , Gudrun Kunst 1

2

King's College Hospital, London, United Kingdom, The Rayne Institute, St Thomas' Hospital, London, United Kingdom Introduction. In the UK perioperative myocardial ischaemia plays a major role in postoperative morbidity and mortality. Therefore, perioperative myocardial protection in patients at risk is of great importance. Anaesthetic preconditioning in patients undergoing coronary artery bypass graft (CABG) surgery can reduce postoperative morbidity and mortality [1]. In addition it was suggested that remote ischaemic preconditioning (RIPC) could reduce the ischaemic marker troponin [2]. We hypothesized that patients benefit from simultaneous remote ischaemic preconditioning and anaesthetic preconditioning, when compared to anaesthetic preconditioning alone. Method. Fifty four patients were prospectively randomized and investigated single blindly. In addition to standardized conventional myocardial protection during CABG surgery, every patient received the volatile anaesthetic isoflurane before bypass. The study was powered at 80%, requiring 25 patients per group for a difference in TnI of 2 ng/mL. 27 patients received three five min. cycles of left upper limb ischaemia (RIPC) after anaesthetic induction, whereas 27 patients had a non-inflated blood pressure cuff around their arm (non-RIPC). The main outcome variable was postoperative troponin I (TnI) measured after 6, 12, 24 and 48 hours. We also analysed brain natriuretic peptide (BNP), creatine kinase (CKMB) and clinical outcome parameters postoperatively. Multilevel models were fitted to the data for statistical analysis. Results. All three markers changed with time. However, our results suggest that there is no statistically significant difference in postoperative TnI, BNP and CKMB between RIPC and nonRIPC. Conclusion. RIPC may not add further myocardial protection on top of a potential benefit by volatile anaesthetics in patients undergoing CABG surgery. References. 1. Landoni G, Biondi-Zoccai GGL, Zangrillo A, et al. Desflurane and sevoflurane in cardiac surgery: a meta-analysis of randomized clinical trials. J Cardioth Vasc Anesth 2007. 21: 502-511. 2. Hausenloy DJ, Mwmaure PK, Venugopal V, et al. Effect of remote ischaemic preconditioning on myocardial injury in patients undergoing coronary artery bypass graft surgery: a randomised controlled trial Lancet 2007; 370: 575-579.

Introduction. Infection is one of the most common complications after cardiac surgery, but is difficult to predict because of the overwhelming inflammatory response (SIRS). Clinical and laboratory monitoring is necessary for its early detection. In the present study we compared standard immune monitoring versus quantification of CD64 on granulocyte cells. Method. From December 2008 to August 2009 we studied 55 patients with fever >38.5°C after cardiac surgery. White blood cell count, C reactive protein (CRP) and CD64 were reported. Statistical analysis with Kruskal-Wallis and Mann Whitney U tests was performed to compare an infection group and a noninfection group. Results and Discussion. Forty nine patients had an infection free hospital course, 7 presented with SIRS criteria and 6 had infections matching the sepsis criteria. Surgical variables are shown in table 1 with comparison between CRP and CD64. Both difference between infection and non-infection groups and between infection and SIRS groups were significant only for CD64. CD64 allows early detection of infection. Table. No infection Infection Patients (no) 49 6 CABG 66.2% 64.8% Cardiopulmonary bypass 87% 84% CRP media (sd) mg/dl 11.04 (6.3) 21 (8.42) CD6 median(sd) ABC =antibody capacity 839 (520.02) 3381 (602.2) Statistical significance CD64 Infection vs. non infection, P 0.0001 SIRS vs. infection, P 0.0027 Statistical significance CRP Infection vs. non infection, P 0.079 SIRS vs. infection, P 0.19

Conclusions. CD64 is a specific marker of infection superior for sensibility and specificity to CRP and helps the clinician towards the appropriate therapy. References. 1. Strohmeyer JC, Blume C, Meisel C, et al. Standardized immune monitoring for the prediction of infections after cardiopulmonary bypass surgery in risk patients Cytometry B Clin Cytom 2003; 53: 54-62. 2. Icardi M, Erickson Y, Kilborn S, et al. CD64 index provides simple and predictive testing for detection and monitoring of sepsis and bacterial infection in hospital patients J Clin Microbiol 2009; 47: 3914-3919.

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O-86 Effectiveness of preoperative single-dose gabapentin on sensory changes and postoperative pain after thoracotomy 1

1

1

Fatma Nur Kaya , Elif Basagan-Mogol , Belgin Yavascaoglu , 1 2 3 Suna Goren , Sibel Gurun , Sami Bayram 1

2

Department of Anaesthesiology and Reanimation, Department 3 of Pharmacology, Department of Thoracic Surgery, Uludag University, School of Medicine, Bursa, Turkey Introduction. Pain occurring in the chest wall following thoracic surgery remains a significant problem, contributing to increased postoperative complications and reduced quality of life after surgery. Persistent dysaesthetic burning pain and aching can occur in up to 50-70% of patients at two months or more after thoracotomy and is generally considered to be neuropathic in origin [1]. Gabapentin binds to the alpha-2-delta subunit of voltage-gated calcium channels and represents a novel class of drug for the treatment of neuropathic and postsurgical pain [2]. The aim of this randomized, double-blind, placebo-controlled study was to evaluate the efficacy of preoperative single-dose gabapentin for the control of post-thoracotomy pain. Method. After ethic committee approval and informed consent, 50 ASA I or III patients undergoing thoracotomy were assigned randomly to receive either 800 mg gabapentin (Group G) or placebo (Group P) orally, 2 h before surgery. Anaesthesia was standardized. Postoperative analgesia was maintained with epidural patient-controlled analgesia using a bupivacaine and fentanyl combination in all patients. Visual analogue scale values and analgesic consumption were evaluated at 2, 4, 8, 16, 24 and 48 h after surgery. The areas of allodynia and pinprick hyperalgesia were measured at 48 h, and days 15 and 30 in the two groups. Independent sample t-test, Mann-Whitney U-test and Wilcoxon’s signed rank test were used to analyse the data statistically. Results. Fentanyl and bupivacaine requirements were lower in group G than group P (P<0.001). The areas of pin-prick hyperalgesia and brush allodynia in group G were smaller than group P, 2 and 15 days and 1 month after surgery (P=0.007 at day 2 for hyperalgesia, P<0.001 for the other variables). Discussion. The results of our study demonstrate that preoperative single-dose gabapentin is effective in reducing postoperative analgesic requirements, hyperalgesia and touch allodynia. References. 1. Rogers ML, Duffy JP. Surgical aspects of chronic postthoracotomy pain. Eur J Cardiothorac Surg 2000; 18: 711716. 2. Gilron I. Gabapentin and pregabalin for chronic neuropathic and early postsurgical pain: current evidence and future directions. Curr Opin Anaesthesiol 2007; 20: 456-472. O-87 Asymptomatic carotid artery stenosis and postoperative cognitive outcome in patients undergoing on-pump coronary artery bypass grafting Ieva Norkiene, Robertas Samalavicius, Irina Misiuriene, Juozas Ivaskevicius Clinic of Anesthesiology and Intensive Care, Vilnius, Faculty of Medicine, Vilnius University, Vilnius, Lithuania Introduction. Postoperative cognitive decline (POCD) is one of the most controversial complications following cardiac surgery. Often taken into account as a natural part of the postoperative period, it affects the recovery period of the patient and

influences quality of life. The aim of our study was to evaluate the incidence of POCD after coronary artery bypass grafting, determine perioperative risk factors and investigate whether asymptomatic carotid artery stenosis, has an impact on postoperative cognition. Method. We collected data of 127 consecutive patients, undergoing on-pump CABG at our institution. Neuropsychological examination consisted of 7 tests (MMSE, Rey auditory verbal test, Trail Making A, B, Digit Span, Cube drawing test). Ultrasound examination of carotid arteries was performed for every patient preoperatively. Results. Early postoperative cognitive decline (POCD) was detected in 46% (n = 59) of patients. Asymptomatic carotid artery stenosis was strongly associated with poor postoperative cognitive outcomes (P=0.0001). Significant reduction in carotid artery lumen of >50% was determined as an independent risk factor for POCD through unvaried analysis (OR 26.9). POCD was associated with age (P=0.04), operation time (P=0.02), low cardiac output perioperativelly (P=0.02), postoperative atrial fibrillation (P=0.01), delirium (P=0.02), mechanical ventilation and ICU time (P=0.01). Table 1. Multivariate logistic regression analysis of risk factors Age >65 years Carotid art. stenosis >50%

Odds Ratio 2.78 26.89

95% confidence interval 1.13 – 6.85 6.44 – 112.34

0.025 <0.001

Operation time >240 min

4.08

1.26 – 13.20

0.019

CMV •360 min

3.33

1.22 – 9.10

0.019

ICU stay •3 days 3.83 1.3 – 11.29 CMV – controlled mechanical ventilation, ICU – intensive care unit.

P

0.015

Discussion. Preoperative carotid artery stenosis of more than 50% is an independent risk factor for development of early postoperative cognitive decline. Reference. 1. Silvestrini M, Paolino I, Vernieri F, et al. Cerebral hemodynamics and cognitive performance in patients with asymptomatic carotid stenosis. Neurology 2009; 72: 1062– 1068. O-88 Cerebral oxygen saturation for risk stratification in cardiac surgery: a prospective pilot study 1

1

1

Matthias Heringlake , Christof Garbers , Ingrid Anderson , Jan 1 1 1 1 Käbler , Hermann Heinze , Julika Schön , Klaus-Ulrich Berger , 2 Thorsten Hanke 1

Department of Anesthesiology, University of Lübeck, Lübeck, 2 Germany, Department of Cardiac and Thoracic Vascular Surgery, Lübeck, Germany

Introduction. Low cerebral oxygen saturation (ScO2), determined by Near-Infrared-Spectroscopy, has been related to increased morbidity after cardiac surgery [1,2]. The present prospective pilot study was designed to determine the usefulness of preoperative ScO2 levels for predicting mortality in a heterogeneous cohort of cardiac surgery patients in comparison with the additive EuroSCORE. Method. 984 patients (491 isolated CABG, 177 combined CABG, and 316 patients undergoing valve or thoracic vascular surgery) undergoing on-pump cardiac surgery were studied. Preoperative ScO2, demographics, relevant surgical data as well as 30- and 90-day mortality were determined. Results. Median EuroSCORE was 5 (range: 0-19). 30 and 90 day mortality were 3.4% and 5.5%. Non-survivors had a lower ScO2 than survivors (P<0.05). Kaplan-Meier statistics revealed that patients with a ScO2 less than 50% absolute had a higher

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mortality (P<0.001). Receiver operating curve analysis revealed an area-under-the-curve (AUC) of 0.69 (95% CI: 0.66 to 0.72; P=0.003) for ScO2 and 0.82 (95% CI: 0.79 to 0.84; P=0.001) for EuroSCORE (P=0.018 for AUC ScO2 vs AUC EuroSCORE). The optimal cut-off value for 30 day mortality was ScO2 <54%. Using this ScO2-value, the optimal cut-off for EuroSCORE (>7), age (>65 years), and duration of surgery (>249 min) as dichotomous variables; stepwise logistic regression revealed that ScO2 (OR: 2.8 (95% CI: 1.3 to 5.9), EuroSCORE (OR: 5.9 (95% CI: 2.5 to 13.7), and age (OR: 3.2 (95% CI: 1.3 to 7.9) were significant (P<0.05) predictors of 30-day mortality. This association was also present in a subgroup of patients older than 65 years. Conclusions. A preoperative ScO2 value below 54% absolute is a significant predictor of 30-day mortality in a heterogeneous cohort of cardiac surgery patients, but has less predictive capacity than the additive EuroSCORE. References. 1. Edmonds HL Jr, Ganzell BL, Austin EH 3rd. Cerebral oximetry for cardiac and vascular surgery. Semin Cardiothorac Vasc Surg 2004: 8: 147-166. 2. Schön et al. Appl Cardiopulm Pathophysiol 2009; 13: 243252. O-89 Fibrinogen reverses the eptifibatide-induced decrease of maximum clot firmness but not impaired platelet aggregation Klaus Görlinger, Günther Oprea, Jürgen Peters, Matthias Hartmann Klinik für Anästhesiologie und Universitätsklinikum Essen, Essen, Germany

Intensivmedizin,

Introduction. Eptifibatide is a reversible GPIIb/IIIa receptor antagonist used to inhibit platelet aggregation in patients with unstable angina or coronary stent implantation. Pharmacological options to reverse eptifibatide`s effect on platelet aggregation and clot firmness have not been described. Since fibrinogen is the main ligand for GPIIb/IIIa receptors, we hypothesized that fibrinogen reverses both eptifibatide-induced inhibition of platelet aggregation and reduction of clot firmness.

Method. Whole blood of 8 healthy volunteers was incubated with eptifibatide (0.015 up to 100 μg/ml) and fibrinogen (0-6.4 g/L) was added to assays. Maximum clot firmness (MCF) was determined by thromboelastometry using tissue factor as activator. Platelet aggregation (presented as area under the curve, AUC, AU x min) was determined by impedance aggregometry after stimulation with TRAP-6. Statistical analysis, means ± SD, by Student`s t-test for independent samples. Results. Eptifibatide (0.2-100 μg/ml) induced a dose-dependent decrease of MCF from 58.6 mm ± 1.5 to 14.0 ± 4.2 (P<0.001), with an ED50 of 12.5 μg/ml. Furthermore, eptifibatide (0.015-2.6 μg/ml) impaired platelet aggregation (779 AUC ± 33 to 48 ± 3, P<0.001), with an ED50 of 0.25 μg/ml. The eptifibatide (12.5 μg/ml) evoked decrease in MCF (32.0 mm ± 4.9) was dosedependently reversed by addition of fibrinogen (72.4 mm ± 10.4, P<0.001). To restore baseline MCF (57.0 mm ± 8.5) 3.2 g/L fibrinogen was necessary, whereas 6.4 g/L resulted in supranormal MCF (72.4 mm ± 10.4, P<0.01). In contrast, fibrinogen (6.4 g/L) had no effect on eptifibatide (0.25 μg/ml) induced inhibition of platelet aggregation (321 AUC ± 84 vs. 286 ± 66, ns). Conclusion. Fibrinogen dose-dependently reverses the eptifibatide-induced decrease in maximum clot firmness but does not restore impaired platelet aggregation. Accordingly, the effect of fibrinogen is not mediated by competitive displacement of eptifibatide by fibrinogen from platelet GPIIb/IIIa receptors but rather is an unspecific effect related to increased fibrin polymnerisation evoked by a higher fibrinogen concentration.