Severe Hypoglycemia While on Intensive Insulin Therapy Is Not an Independent Predictor of Death After Trauma

Background: Fear of the adverse effects of hypoglycemia has limited the widespread application of intensive insulin therapy (goal, 80-110 mg/dL) in the trauma population. We hypothesized that severe hypoglycemia (SH; <= 40 mg/dL) was not an independent predictor of mortality in the trauma population. Methods: An analysis of critically ill trauma patients treated with intensive insulin therapy from November 2005 to May 2008 was performed. The primary outcomes of interest were any episode of SH (<40 mg/dL) and all-cause inhospital mortality. Multivariate logistic regression was used to estimate the independent relationship between hypoglycemia and death. Results: Fifty-seven thousand two hundred eighty-four data entries (1,824 patients) from the euglycemia protocol were analyzed (mortality = 16.0%). Median glucose was 119 mg/dL, with 43% of values between 80 mg/dL and 110 mg/dL, 81% between 80 mg/dL and 150 mg/dL, and 0.3% <40 mg/dL. There were 126 severe hypoglycemic episodes in 111 patients (6.1% of the patients). Multivariate logistic regression revealed that SH was not independently associated with death after adjusting for other known risk factors (odds ratio, 1.244; 95% confidence interval, 0.853-1.816; p = 0.257). Conclusion: Hypoglycemia may be an unavoidable byproduct of tight glucose control with 6.1% of the patients experiencing a severe hypoglycemic event (<40 mg/dL). Hypoglycemia is not an independent predictor of death. Hypoglycemia is a statistical probability of time spent on protocol rather than an event leading to death. These data suggest that lower glucose ranges should be targeted in the trauma population without fear of hypoglycemia's adverse effect on mortality.