Early insulin resistance in severe trauma without head injury as outcome predictor? A prospective, monocentric pilot study

Background: Hyperglycemia following major trauma is a well know phenomenon related to stress-induced systemic reaction. Reports on glucose level management in patients with head trauma have been published, but the development of insulin resistance in trauma patients without head injury has not been extensively studied. The aim of this study was therefore to investigate the prognostic role of acute insulin-resistance, assessed by the HOMA model, in patients with severe trauma without head injury. Methods: All patients consecutively admitted to the Intensive Care Unit (ICU) of a tertiary referral center (Careggi Teaching Hospital, Florence, IT) for major trauma without head injury (Jan-Dec 2010) were enrolled. Patients with a previous diagnosis of diabetes mellitus requiring insulin therapy or metabolism alteration were excluded from the analysis. Patients were divided into "insulin resistant" and "non-insulin resistant" based on the Homeostasis Model Assessment index (HOMA IR). Results are expressed as medians. Results: Out of 175 trauma patients admitted to the ICU during the study period, a total of 54 patients without head trauma were considered for the study, 37 of whom met the inclusion criteria. In total, 23 patients (62.2%) resulted insulin resistant, whereas 14 patients (37.8%) were non-insulin resistant. Groups were comparable in demographic, clinical/laboratory characteristics, and severity of injury. Insulin resistant patients had a significantly higher BMI (P=0.0416), C-reactive protein (P=0.0265), and leukocytes count (0.0301), compared to non-insulin resistant patients. Also ICU length of stay was longer in insulin resistant patients (P=0.0381). Conclusions: Our data suggest that admission insulin resistance might be used as an early outcome predictor.