Enzymatic and hemodynamic changes after short term hepatic outflow occlusion in the dog

In normal mongrel dogs, outflow occlusion of 15 or 30 minutes duration was produced by clamping both the suprahepatic and suprarenal portions of the vena cava. One dog died immediately after release of occlusion; two dogs died from recurrent hypotension between six and 24 hours postoperatively. The other five dogs survived for three days, at which time an autopsy was done. During outflow occlusion, the blood pressure fell in all dogs, as did the central venous pressure. The pulse rate decreased during, and after, occlusion but toward a tendency of gradual recovery. A significant drop in pH and base excess of arterial blood was seen after occlusion. Although a steady, but not substantial, increase in hemoglobin and hematocrit values was noted, there were no remarkable changes in the blood coagulation system. Significant increases in serum glutamic-oxalacetic transaminase, glutamic-pyruvic-transaminase, lactic dehydrogenase, acid phosphatase and beta-glucuronidase activities were observed from immediately after release of occlusion, but alkaline phosphatase values increased much later than did these. Thus, hepatic outflow occlusion, even if it is short, seems to be dangerous in the dog, since it produces hypotension, metabolic acidosis and diffuse damage as well as disruption of the parenchyma of the liver.