Background and Goal of Study: The preoperative carbohydrate loading that is recommended in the enhanced recovery after surgery (ERAS) protocol enhances insulin action by approximately 50% . In some Japanese hospitals, preoperative oral rehydration therapy is performed for preventing dehydration during surgery. We hypothesized that preoperative oral rehydration therapy with a 2.5% carbohydrate beverage that is widely used in Japan can enhance insulin action. Therefore, we investigated the effect of this 2.5% carbohydrate beverage on insulin action in healthy volunteers.
Material and methods: Six healthy volunteers participated in this crossover randomized study. The participants were segregated into 2 groups: a control group (C group) and an oral rehydration therapy with 2.5% carbohydrate beverage group (OS group). The C group fasted from 9 pm onward on the evening before the investigation, and subjects were allowed to drink only water; conversely, the OS group fasted from 9 pm onward and drank 500 mL of the beverage containing 2.5% carbohydrate (OS-1; Otsuka Pharmaceutical Factory, Tokushima, Japan) between 9 pm and 12 pm and again at 6.30 am. At 8.30 am, a hyperinsulinemic normoglycemic clamp was initiated using an artificial pancreas STG-22 (Nikkiso, Tokyo, Japan). Insulin resistance was evaluated in both groups using the glucose infusion rate. Statistical analysis was performed, and P values less than 0.05 were considered statistically significant.
Results and Discussion: Subject age was 36 ± 8 years (mean ± SD), and body mass index was 23 ± 3 kg/m2. Blood glucose levels at the initiation of the clamp procedure were 92 ± 4 mg/dL for the C group and 92 ± 3 mg/dL for the OS group; thus, the difference was not statistically significant (P = 0.99). However, the glucose infusion rate for the OS group was significantly higher than that of the C group (8.6 ± 1.5 vs 6.8 ± 2.0 mg/kg/min, P = 0.009). The efficacy of insulin action in the OS group was less than that of insulin action due to the 12.6% carbohydrate beverage, which is recommended in the ERAS. Therefore, we considered that carbohydrate dose is the key factor for improving insulin action.
Conclusion: An oral rehydration solution containing 2.5% carbohydrate enhanced the action of insulin more than fasting alone.
1. Svanfeldt M, et al. Clin Nutri. 2005;24:815-21.