Validation of the DeLiT Trial intravenous insulin infusion algorithm for intraoperative glucose control in noncardiac surgery: a randomized controlled trial

Abstract

Purpose: A safe and effective insulin infusion algorithm that achieves rigorous intraoperative glycemic control in noncardiac surgery has yet to be formally characterized and evaluated. We therefore report the validation of the DeLit Trial insulin infusion algorithm.

Methods: Patients scheduled for major noncardiac surgery were randomized to a target intraoperative blood glucose concentration of 4.4-6.1 mmoL·L(-1) (80-110 mg·dL(-1)) intensive group or 10-11.1 mmoL·L(-1) (180-200 mg·dL(-1)) conventional group. Glucose was managed with a dynamic intravenous insulin infusion algorithm. We compared the randomized groups on glucose time-weighted average (TWA), proportion of time spent within target, number of severe (< 2.2 mmoL·L(-1) or < 40 mg·dL(-1)) or moderate (< 2.8 mmoL·L(-1) or < 50 mg·dL(-1)) hypoglycemic episodes, and within-patient variability in glucose concentrations expressed as standard deviation from the patient mean.

Results: One hundred eighty-seven patients were assigned to intensive glucose control, and 177 patients were assigned to conventional glucose control. Median (lower quartile value [Q1], upper quartile value [Q3]) of intraoperative TWA for the intensive vs conventional groups was 6 [5.6, 6.7] mmoL·L(-1) vs 7.7 [6.9, 9.2] mmoL·L(-1), respectively; P < 0.001. The intensive group spent 49% (29, 71) of the time within target, substantially more time than the conventional group spent either within the intensive target or within its own target (both P < 0.001). The intensive group had slightly lower within-patient glucose variability than the conventional group (0.9 [0.7, 1.3] mmoL·L(-1) vs 1.3 [0.8, 1.8] mmoL·L(-1), respectively; P < 0.001). Three patients had moderate hypoglycemia (intensive group), but none experienced severe episodes.

Conclusion: Tight intraoperative glucose control in noncardiac surgery can be maintained successfully without serious hypoglycemic episodes. (ClinicalTrials.gov number, NCT00433251).