Increased intestinal permeability: implications for thoracoabdominal aneurysm repair.

Coagulopathy and massive bleeding plays a major role in the mortality of thoraco-abdominal aneurysm repair. Increasing supraceliac aortic cross-clamp time from 0 to 90 minutes increases the degree of disseminated intravascular coagulation, which occurs as a result of occlusion and reperfusion of the superior mesenteric artery. The purpose of this study was to investigate the mechanism of the superior mesenteric artery reperfusion disseminated intravascular coagulation. Twenty dogs were divided into four groups: cross-clamp time of 30 minutes; cross-clamp time of 60 minutes; cross-clamp time of 90 minutes; and control. Permeability was determined by lactulose/mannitol absorption. The venous effluent was sampled for endotoxin, potassium, bacteria, and pH every hour and urine was collected for six hours. Lactulose absorption was significantly higher in all of the experimental groups. There was increased permeability in the 60 and 90 minute groups which correlated significantly with time. Venous endotoxin, potassium, and blood cultures for bacteria did not change significantly. The pH was significantly lower every hour for six hours in the 90 minute group. These data suggest that intestinal permeability is increased with supraceliac aortic clamping and can be kept to a minimum for clamp times of under one hour.