Correspondence 287 Editor’s note Moreover such concerns would not appear to apply to the use of intrathecal bupivacaine.2 REFERENCES 1. Hampl K, Pargger H, Schneider M, Gut J, Drewe J, Drasner K. The incidence of transient radicular irritation after spinal anesthesiais similar with 5% and 2% lidocaine. Anesth Analg, in press.
Electrocardiographicchangesduring cesareansection: a review We read with great interest the review article of Dr Burton et al (International Journal of Obstetric Anesthesia 1996; 5: 47-53) regarding electrocardiographic changesduring caesareansection, and wish to report a recent case where ECG changes occurred with a rise in cardiac enzymes suggestingmyocardial infarction. A 28-year-old primigravid Asian lady with no cardiac problems and no risk factors for coronary artery disease underwent an emergency caesarean section for fetal distress, following induction of labour for intrauterine growth retardation. Ringer’s lactate solution 1 L was infused intravenously before performing spinal anaesthesiaat the third lumbar interspacewith a mixture of hyperbaric 0.5% bupivacaine 2 ml and 0.5 mg diamorphine. Preoperative blood pressure was 117/73 mmHg and systolic arterial pressurewas maintained above 90 mmHg throughout the caesarean section with incremental boluses of ephedrine up to a total of 30 mg. Supplemental oxygen was given via a facemask. ECG monitoring (CM, lead configuration) during the procedure showed marked ST segment elevation after the start of surgery but before delivery and persisted throughout the operation, although the patient remained asymptomatic. Otherwise the operation was uneventful with minimal blood loss. Postoperatively she was transferred to the Coronary Care Unit where 12 lead ECG showed widespread ST segment depression which resolved within the next 24 h. However, there was minor R wave amplitude reduction. The creatinine kinase MB rose to a maximum of 142 iu/L (upper limit of normal 25 iu/L) 12 h after surgery. The patient was reviewedby the consultant cardiologist who performed an echocardiogram at 4 days and an exercise test at 4 weeks postoperatively, both of which were normal. He concluded that the patient had sustained a minor myocardial infarction as a consequence of coronary artery spasm but did not feel coronary angiography was indicated. The patient has remained well over the past 6 months.
2. Hampl K, Schneider M, Ummenhofer W. Drewe J. Transient neurologic symptoms after spinal anesthesia.Anesth Analg 1995: 81: 1148-1153.
Kenneth Drasner, MD Associate Professor of Anesthesia University of California, San Francisco San Francisco. USA
Although we agreewith Dr Burton et al that there is a lack of apparent morbidity associated with ST depression during caesareansection, we feel that ST segmentelevation warrants postoperative observation in a coronary care unit and a cardiology opinion should be sought. Dr R. M. Venn, MBBS Dr G. Dissanayake,MD FFA Dr J. F. Sneddon, MA MRCP Dr L. S. St John-Jones,MBBCh FFA Anaesthetic Department, Crawley Hospital, West Sussex, UK In reply We thank Dr Venn and colleaguesfor their interest in our article.’The casethey report is interesting, particularly becausetheir patient had ST elevation during cesareansection, which may be more premonitory of myocardial infarction than ST depression. The bulk of the literature we revieweddealt with ST depression. One diagnosis that merits consideration in this patient is paradoxical air embolus to the coronary circulation.2 An echocardiographic bubble study would determine the presenceof a patent foramen ovale. It is well known that air embolism is a recognizedcomplication of cesareansection, and also that IO-20% of the adult population has a patent foramen ovale. Further, as Goldman et al point out, care must be used in interpreting cardiac enzyme changes in the perioperative period.3We agreewith consultation of a cardiologist to assist in patient management;however, admission to coronary care units should be reserved for patients with clear cut myocardial infarction in evolution, unstable angina, or hemodynamic instability.4 In this case,we believe that an intermediate care bed with ECG monitoring only would suffice. A. Burton, MD Departmentof Anesthesiology,UTMB. Texas,USA W. Camann, MD Department qf Anesthesiu, Brigham and Women’sHospital, Boston, USA