An insulin infusion protocol in critically ill cardiothoracic surgery patients

BACKGROUND: Critically ill cardiothoracic patients are prone to hyperglycemia and an increased risk of surgical site infections postoperatively. Aggressive insulin treatment is required to achieve tight glycemic control (TGC) and improve outcomes. OBJECTIVE: To examine and report on the performance of an insulin infusion protocol to maintain TGC, defined as a blood glucose level of 80-150 mg/dL, in critically ill cardiothoracic surgical patients. METHODS: A nurse-driven insulin infusion protocol was developed and initiated in postoperative cardiothoracic surgical intensive care patients with or without diabetes. In this before-after cohort study, 2 periods of measurement were performed: a 6-month baseline period prior to the initiation of the insulin infusion protocol (control group, n = 174) followed by a 6-month intervention period in which the protocol was used (TGC group, n = 168). RESULTS: Findings showed percent and time of blood glucose measurements within the TGC range (control 47% vs TGC 61%; p = 0.001), AUC of glucose exposure >150 mg/dL versus time for the first 24 hours of the insulin infusion (control 28.4 vs TGC 14.8; p < 0.001), median time to blood glucose <150 mg/dL (control 9.4 h vs TGC 2.1 h; p < 0.001), and percent blood glucose <65 mg/dL as a marker for hypoglycemia (control 9.8% vs TGC 16.7%; NS). CONCLUSIONS: An insulin infusion protocol designed to achieve a goal blood glucose range of 80-150 mg/dL efficiently and significantly improved TGC in critically ill postoperative cardiothoracic surgery patients without significantly increasing the incidence of hypoglycemia.