Twenty-six hepatic resections were performed using vascular clamping lasting more than one hour. The average duration of continuous normothermic ischemia was 67.0 +/- 7.5 minutes (plus or minus standard error of the mean) (range of 60 to 85 minutes). Vascular occlusion consisted of simple portal triad clamping in 14 patients and of hepatic vascular exclusion in 12. Extensive hepatectomy was performed upon more than 80 percent of the patients. One postoperative death was recorded. Extensive complications occurred in eight patients, including one case of hepatic failure. Postoperative changes in hepatic function tests were mild and transient. The rate of postoperative complications was higher in the group of patients with chronic hepatic disease (77.8 versus 11.8 percent, p < 0.005). Prolonged hepatic ischemia should not be considered a risk factor in patients with normal livers, whereas morbidity and mortality rates are seriously affected by the presence of chronic hepatic disease.