253 Dr. Lister says in his article, if the liberation of thrombokinase predisposed to the condition, then such operations as IIalstead’s amputation of the breast or nephrectomy should show a high rate of incidence," but this is not so, as in these operations, although thrombokinase is liberated, as it is in all operations. the other factor, stasis of the blood in the large veins. is not present, or at least not in the same degree as when an abdominal incision hasbeen made. As proving the importance of this. substance, thrombokinase, as a factor in the formation of clotting, there is an old but interesting experiment. If blood is drawn off from the centre of a large bloodvessel by means of a needle and syringe, greatcare being exercised to prevent any possible contamination of the blood with any substance not normally present in the blood itself, the blood so obtained will not clot at all. It will in fact go bad and decompose eventually without clotting. Dr. Lister’s paper, has I believe, helped very much in clearing up some of the debatable points in the difficult problem of post-operative thrombosis and embolism, and demonstrates how useful the statistical methods can be when properly carried out. Our knowledge is still very deficient, and further light is badly wanted on the physiological and experimental side of the problem, especially in relation to the exact mechanism of intravascular clotting, and a more exact knowledge of the physiology of the condition might, and probably would, go a long way to solvethe surgeon’s problem of how to prevent his patients PULMONARY EMBOLISM FOLLOWING getting pulmonary embolism after operations. It OPERATION. is a subject for regret that in these days the To the Editor of THE LANCET. physiologist and the surgeon are not in closer touch. In the present state of our knowledge I doubt if SIR.—Dr. W. A. Lister’s statistical study of there are any means known to us of either preventing, post-operative pulmonary embolism (THE LANCET, or dealing with, the condition, which are of any value. Jan. 15th, p. 111). is a most valuable contribution to movement and massage are doubtful expedients, our very limited knowledge of this difficult, but most as I believe that quite often the clot forms either on important problem. I am gratified to find that the operating table, or before the patient is round from Ur. Lister’s figures tend to confirm several of the the anaesthetic, and under such circumstances these conclusions.’ which I arrived at in 1921, but which are measures will do harm rather than good. It is full still not generally admitted. Perhaps the most time that we did know how to prevent the condition important of these is that sepsis is not a factor of as it is accountable for quite a considerable number of importance. A great many surgeons still believe disasters, and the general impression among surgeons that sepsis in some form is the main factor in the is that it is becoming more frequent as a complication production of thrombosis after operation. These of abdominal operations. figures, which are much more complete than any I am. Sir. vours faithfully. hitherto produced, give very strong evidence that J. P. LOCKHART-MUMMERY, F.R.C.S. sepsis cannot be considered an important factor. ’, Hyde Park-place, W., Jan. 22nd, 1927. Dr. Lister also confirms rny conclusion that venous stasis in the large venous trunks of the abdomen is the main factor, and his argument that this stasis OBESITY AND TEMPERAMENT. tends to be produced as a secondary result of an To the Editor of The LANCET. abdominal incision is sound. His contention is that the pain caused by any movement of the abdominal SIR,—After reading of the Italian Premiere wall tends to laxnper the action of the diaphragm, alleged dislike for obese people, I thought it might which is necessary for maintaining the flow of blood be of interest to the temperamental characteranalyse through the great abdominal veins. I suggest that istics displayed by the fat and the lean as met with the presence of a tight bandage round the abdomen in general practice. Though there may be exceptions, is also a factor of importance in hampering the the metabolic processes in the adipose are usually excursions of the abdominal wall. slower than in the lean, and this probably accounts The difliculty in accepting this theory of venous for the good nature and easy going character usually stasis is, as I pointed out five years ago, that experi- displayed by fat people. The slim figure demanded mental evidence shows that venous stasis alone cannot by modern fashion has led to innumerable cases of produce intravascular clotting. The ligature of a dieting among obese women, and I have noted vein in two places, so as to produce complete stasis of how a previously contented, cheerful and placid the contained blood, does not result in the formation individual has. on attaining a marked reduction in of a thrombus within that vein, even in two weeks. her weight, become irritable, sullen, and often Some other factor must therefore be present before definitely bad tempered. I admit that with moderate stasis is able to produce intravascular clotting. reduction in weight in cases where the obesity has I suggested that a substance present in all tissues, been marked activity of both body and mind is but normally not present in blood—namely. usually increased, but if the reducing process has thrombokinase, is the factor. This substance is been carried too far; pronounced lassitude with nervous liberated whenever tissues are injured, as by an irritability occurs. Like the Caesar who preferred operation or fracture of a bone, or even normal fat men around him complaining that "Yon Cassius. If stasis in the veins coincides with the hath a lean and hungry look," I think most of us childbirth. liberation of thrombokinase owing to an injury, have learnt to expect and discover geniality and then both the factors necessary for the production sociability among those with a leaning to adipusity. of a thrombus are present and a clot may form. T am- Sir. vours faithfully. ALFRED A. MASSER. M.B., Ch.B 1 Proc. Roy. Soc. Med., Surg. Sect., 1921-22. Penistone, Jan. 10th, 1927. bucket. The fluid measured 40 pints and was quite clear. It was my intention, then, to give her spinal analgesia, but she was so deeply narcotised that I extended my incision considerably without even further local analgesia and started to strip it. To rny surprise I found I was not in the abdominal cavity. The cyst was extraperitoneal and all the abdominal contents were packed away into the The cyst wall was upper part of the abdomen. gradually stripped off ; no pedicle was found. A large drainage-tube was pushed through close to the centre of the crest of the ilium and the abdominal wall sutured. Free sanious oozing took place through the tube which was shortened day by day and removed on the sixth. The intestines gradually The woman came back into their normal position. made an uneventful recovery and went home on the seventeenth day. This was, I suppose. a pelvic cyst which gradually stripped up the peritoneum as it extended upwards. I should be glad to hear any suggestion as to its possible origin. To me it was remarkable to be able to perform an extensive operation under a single injection of morphia and hyoscine. T am. Sir. vours faithfully. F. J. W. PORTER. Karachi, Dec. 30th, 1926. Major, R.A.M.C. (retd.).