Disseminated intravascular coagulation as a result of supraceliac clamping: implications for thoracoabdominal aneurysm repair.

Massive coagulopathy and bleeding continues to play a major role in the operative mortality and perioperative multi-system failure of patients requiring elective thoracoabdominal aneurysm repair. It was the purpose of this study to determine the coagulation defect that occurs with supraceliac aortic clamping and the effects of increasing aortic cross-clamp time (AXCT) on the coagulation system and its recovery. Through a standard thoracoabdominal incision, 16 mongrel dogs had their aortas cross-clamped simultaneously just above the diaphragm and at the aortic bifurcation. Animals were divided into four groups of four animals each; sham operation, 30 minute AXCT, 60 minute AXCT, and 90 minute AXCT. Central venous blood was sampled prior to aortic cross clamping (AXC), during AXC and 1 hour, 2 hours, 5 hours, 7 hours, 12 hours, and 24 hours after the clamp was removed. All samples were assayed for platelets, fibrinogen, fibrin split products, prothrombin time (PT) and partial thromboplastin time (PTT). Platelets and fibrinogen decreased as PT and PTT increased with increasing AXCT consistent with disseminated intravascular coagulation (DIC) (P less than .001). Fibrin split products were positive in the 90 minute AXCT group only. The drop in platelets was greater for increasing AXCT and continued to fall in the 30, 60 and 90 minute AXCT groups at 24 hours (p less than .001). Fibrinogen dropped to the lowest levels between two and twelve hours after AXC and returned to normal at twenty-four hours in the 60 and 90 minute AXCT groups (p less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)