Morbidity in diabetic and nondiabetic patients after abdominal surgery

Morbidity after abdominal surgery was retrospectively investigated in 79 patients with diabetes mellitus and in 79 nondiabetic controls matched for type of surgery (biliary, gastric or colonic), sex, age, body weight and complicating cardiovascular disease. There were 20 complications (including 2 in each of 4 patients) in the diabetic group and 18 (2 patients with 2 complications) among the controls, with no tendency to specific complications in the diabetics. The difference in complication rate was not statistically significant. The mean blood glucose level preoperatively and in the first four postoperative days did not differ significantly between the diabetics with and those without postoperative complications. The risk of overlooking (type II error) a 25% heightened complication rate among the diabetic patients was calculated to be less than 30%, and the risk of overlooking a 50% increase was less than 8%. The authors conclude that elective abdominal surgery in diabetic patients is not burdened by clinically significant increase of postoperative morbidity.