Influence of anesthetic agent on survival following hemorrhage.

One hundred and twenty-eight Sprague-Dawley rats were each anesthetized with one of four anaesthetics and subjected to a standard hemorrhage protocol to determine the effects of anesthetics on survival following hemorrhage. The anesthetics studied were: halothane, 1.26 vol per cent; fluroxene, 4.5 vol per cent; pentobarbital, 50 mg/kg ip; ketamine, 125 mg/kg, im. Mean arterial pressure was conrolled at 40 torr during 60 minutes of hemorrhage. Cumulative survival rates were determined at the end of hemorrhage and 24 hr, 48 hr, 72 hr, and 7 days after hemorrhage. Twenty-four-hour survival rates were: halothane, 50.0 per cent; fluroxene, 56.3 per cent; pentobarbital, 59.4 per cent; ketamine, 84.4 per cent. Seven-day survival rates were: halothane, 46.9 per cent; fluroxene, 18.7 per cent; pentobarbital, 53.1 per cent; ketamine; 81.3 per cent. Survival rates were significantly higher (P less than 0.05) in animals anesthetized with ketamine compared with survival rates associated with the other anesthetics. Long-term (72-hr and seven-day) survival rates were significantly (P less than 0.05) lower in animals anesthetized with fluroxene. Microscopic examination of livers and small intestines revealed significantly fewer (P less than 0.05) athologic changes in the splanchnic organs of hemorrhaged rats anesthetized with ketamine compared with animals anesthetized with the other drugs.