Lipid fuel metabolism after abdominal surgery

The work investigated fuel interrelationships in surgical patients infused with saline (Group I) or glucose (Group II) (13 patients in each group) on the day of surgery and subsequently maintained solely on saline until the fifth postoperative day. Blood concentrations of non-esterified fatty acids (NEFA) and ketone bodies were markedly increased in response to surgical stress on the day of surgery only in patients who were not administered carbohydrate. Increased concentrations of lactate and glucose were observed on the day of surgery in patients infused with either saline or glucose. As both fatty acid and ketone body concentrations were decreased by glucose infusion, impaired glucose utilization immediately after surgery is not a simple consequence of increased oxidation of lipid fuels. Glucose and lactate concentrations declined after the day of surgery. Despite a progressive fall in plasma non-esterified fatty acid concentrations from the first to fifth post-operative days, blood ketone body concentrations were strikingly elevated in both groups of patients. The findings emphasize the role of the liver in post-operative fatty acid turnover.