Intravenous bolus-infusion versus sliding scale of insulin for intra-operative glycemic control in elective laparotomy surgeries

Abstract
Background
The aim of this study was to assess the bolus-infusion to the sliding scale of insulin approaches, regarding percentage of the operative time with the target capillary blood glucose (CBG) range, total insulin units given to the patients, development of hypoglycemia, and the peri-operative changes in serum potassium (s.k) in elective laparotomy surgeries. Sixty patients, American Society of Anesthesiologists (ASA) physical status II, were randomly divided to either the bolus-insulin infusion (BII) group, or the sliding scale of insulin (SSI) group.
Results
The intra-operative target CBG range was achieved in both groups, with no statistically significant difference between them. However, in the post anesthesia care unit (PACU), the number of patients who achieved the target CBG range was significantly more in the BII group. The decrease in the CBG was statistically significant in the SSI group than in the BII group; starting from 30 minutes after the initial intra-venous (IV) insulin injected, to 240 minutes intra-operatively and in the PACU. No patient in either groups developed hypoglycemia. The mean intra-operative time needed to achieve the target CBG range was statistically significant less in the SSI group. The mean percentage of the operative time with the target CBG range was statistically non-significant higher in the SSI group. The mean total insulin units given were statistically non-significant higher in the SSI group. The peri-operative changes in s.k were statistically non-significant between the two groups.
Conclusions
The BII approach slowly achieved the target CBG range intra-operatively and maintained this target in the PACU, with mean 54.6 ± 28.9% operative time with the target CBG range, and with less mean total insulin units needed than the SSI approach.