Decreased glucose utilization during prolonged anaesthesia and surgery

We studied the influence of prolonged anaesthesia and surgery on glucose metabolism by means of the euglycaemic insulin clamp method in eight patients who underwent prolonged surgery. Eleven patients who underwent surgery of short duration served as a control group. Plasma concentrations of catabolic hormones were measured simultaneously. Glucose utilization during prolonged anaesthesia, (PA) group, was lower than that in the control group (P less than 0.01) (glucose utilization 7.59 +/- 0.73 mg.kg-1.hr-1 in the control group vs 4.03 +/- 0.71 mg.kg-1.hr-1 in PA group respectively). There were no significant differences in plasma catecholamine and glucagon concentrations between the PA and control groups. Plasma-free fatty acid levels increased significantly in the PA group before the euglycaemic insulin clamp (free fatty acid level: 0.496 +/- 0.053 mmol.L-1 in the control group, vs 0.834 +/- 0.103 mmol.L-1 in the PA group at the pre-clamp period, P less than 0.01). Tissue resistance to exogenous insulin increased during prolonged anaesthesia and surgery although there were no significant changes in plasma catabolic hormone levels.