Effects of preoperative and intraoperative glucose administration on glucose use and fat catabolism during laparotomy under sevoflurane anesthesia in fasted rats

Abstract

Preoperative fasting as well as surgical stress significantly modifies metabolisms. Recent studies reported the possible advantageous effects of glucose administration on perioperative metabolisms; however, the underlying mechanisms have not been fully elucidated. Rats were allocated to three groups. During the fasting period, groups A and B were administered water, but group C was administered glucose. During laparotomy and the insulin tolerance test (ITT) under sevoflurane anesthesia, group A was administered saline, but groups B and C were administered glucose. During laparotomy, group C showed higher glucose levels and lower β-hydroxybutyrate (β-OHB) levels than group A, and group B showed more decreases in β-OHB levels than group A without differences in changes in glucose levels. Insulin levels and insulin sensitivity during laparotomy were similar among the three groups. No significant difference in insulin sensitivity was also confirmed in ITT. In conclusion, perioperative glucose administration suppresses lipolysis without affecting insulin secretion and sensitivity.

Keywords: Adipocytokine; Insulin secretion; Insulin sensitivity; Intraoperative glycemic control; β-Hydroxybutyrate.

Fig. 1

The experimental protocol. All rats were fasted for 12 h prior to the experiment. During the fasting period, rats in groups A and B were provided with water, whereas rats in group C were provided with 12.5 % glucose. General anesthesia was induced and maintained using sevoflurane in all rats. After surgical preparation, rats in group A were administered saline intravenously, whereas rats in groups B and C were administered saline with glucose intravenously. A 30-min stabilization period was allowed. Then, all rats underwent laparotomy and the insulin tolerance test. T1 just before induction of anesthesia. T2 just before laparotomy. T3 just after laparotomy (i.e., just before insulin administration). T4 at 15 min after insulin administration

Fig. 2

Changes in blood glucose levels during the expriments. a Shows the increases in blood glucose levels during preparations [Δglucose (preparations)]; there was no significant difference among the three groups (P > 0.05, 1-way ANOVA). b Shows the increases in blood glucose levels during laparotomy [Δglucose (laparotomy)]; there was no significant difference among the three groups (P > 0.05, 1-way ANOVA). c Shows the decreases in blood glucose levels during the insulin tolerance test [Δglucose (ITT)]; there was no significant difference among the three groups (P > 0.05, 1-way ANOVA)

Fig. 3

Changes in blood β-hydroxybutyrate levels during the experiments. a Decreases in blood β-hydroxybutyrate levels during preparations (Δβ-OHB [preparations]); there was no significant difference among the three groups (P > 0.05, 1-way ANOVA). b Decreases in blood β-hydroxybutyrate levels during laparotomy (Δβ-OHB [laparotomy]); there were significant differences between groups A and B (adjusted P = 0.0214, Tukey-Kramer HSD test) and between groups A and C (adjusted P = 0.0048, Tukey-Kramer HSD test), while no significant difference was detected between groups A and C (adjusted P > 0.05, Tukey-Kramer HSD test)