Implementation of perioperative blood glucose monitoring and insulin infusion protocol can decrease postoperative infection rate in diabetic patients undergoing elective craniotomy: An observational study

Background: Severe perioperative hyperglycemia (SH) is a proven risk factor for postoperative complications after craniotomy. To reduce this risk, it has been proposed to implement the standardized clinical protocol for scheduled perioperative blood glucose concentration (BGC) monitoring. This would be followed by intravenous (IV) insulin infusion to keep BGC below 180 mg/dl in the perioperative period. The aim of this prospective observational study was to assess the impact of this type of protocol on the postoperative infection rate in patients undergoing elective craniotomy. Methods: A total of 42 patients were prospectively enrolled in the study. Protocol included scheduled BGC monitoring in the perioperative period and rapid-acting insulin IV infusion when intraoperative SH was detected. The diagnosis of infection (wound, pulmonary, blood stream, urinary tract infection or central nervous system infection) was established according to CDC criteria within the first postoperative week. A previously enrolled group of patients with sporadic BGC monitoring and subcutaneous insulin injections for SH management was used as a control group. Results: An infectious complication (i.e., pneumonia) was diagnosed only in one patient (2 %) in the prospective group. In comparison with the control group, a decrease in the risk of postoperative infection was statistically significant with OR = 0.08 [0.009 - 0.72] (p = 0.02). Implementation of the perioperative BGC monitoring and the correction protocol prevented both severe hyperglycemia and hypoglycemia with BGC < 70 mg/dl. Conclusion: Scheduled BGC monitoring and the use of low-dose insulin infusion protocol can decrease the postoperative infection rate in patients undergoing elective craniotomy. Future studies are needed to prove the causality of the implementation of such a protocol with an improved outcome