Loss of Blood as a Factor in Death from Acute Portal Obstruction

Abstract

Sudden occlusion of the portal vein is followed very rapidly by shock and death within a few hours. The reason has never been explained. The blood pressure falls within a few minutes and soon drops to a shock level and continues downward until exitus. A decrease in the thrombocyte count and in clotting time has been recorded recently. 1 With the idea that a toxemia similar to that assumed to occur in low intestinal obstruction and strangulation might be present, we examined the lymph from the thoracic duct, the systemic blood and the portal blood from animals before and after portal ligation. By injecting the material into guinea pigs no differences in toxicity were observed.

Sufficient blood may have been lost from the general circulation into the engorged mesenteric veins and intestinal capillaries in dogs with obstruction of the portal vein to account for the rapid death. To investigate this both cats and dogs were used. Pairs of the same age, weight and sex were selected as far as possible and starved for 24 hours. The same anesthetic was employed and similar laparotomy at the same time was performed in each pair of animals. A ligature was placed around the lower rectum in each to prevent escape of intestinal contents. The portal vein was isolated in each and was tied in one. As soon as the one with ligation died the control was killed. The entire gastro-intestinal tract of each from the cardia to the anus was removed in toto including the spleen and with avoidance of the loss of fluid from them. The results are shown in Table I and are expressed in terms of weight of intestinal tract as percentage of the body weight.