To Örebro University

Background & aims: Postoperative metabolism is characterised by insulin resistance and a negative whole-body nitrogen balance. Preoperative carbohydrate treatment reduces insulin resistance in the first day after surgery. We hypothesised that preoperative oral carbohydrate treatment attenuates insulin resistance and improves whole-body nitrogen balance 3 days after surgery.

Methods: Fourteen patients undergoing total hip replacement were double-blindly randomised to preoperative oral carbohydrate treatment (12.5%, 800 + 400 ml, n = 8) or placebo (n = 6). Glucose kinetics (6,6-D2-glucose), substrate utilisation (indirect calorimetry) and insulin sensitivity (hyperinsulinaemic-euglycaemic clamp) were measured preoperatively and on the third day after surgery. Nitrogen losses were monitored for 3 days after surgery. Values are mean (SEM). Analysis of variance (ANOVA) statistics were used.

Results: Endogenous glucose release during insulin infusion increased after surgery in the placebo group. Preoperative carbohydrate treatment, as compared to placebo, significantly attenuated postoperative endogenous glucose release (0.69 (0.07) vs. 1.21 (0.13)mg kg(-1) x min(-1), P < 0.01), while whole-body glucose disposal and nitrogen balance were similar between groups.

Conclusions: While insulin resistance in the first day after surgery has previously been characterised by reduced glucose disposal, enhanced endogenous glucose release was the main component of postoperative insulin resistance on the third postoperative day. Preoperative carbohydrate treatment attenuated endogenous glucose release on the third postoperative day.