The Southwestern Surgical Congress Risk factors for delirium after major trauma Erik M. Angles, B.S. a , Thomas N. Robinson, M.D. a, *, Walter L. Biffl, M.D. a,b , Jeff Johnson, M.D. a,b , Marc Moss, M.D. c , Zung V. Tran, Ph.D. d , Ernest E. Moore, M.D. a,b a Department of Surgery, University of Colorado at Denver, Health Sciences Center, 12631 East 17th Ave., Mail Stop C313, PO Box 6511, Aurora, CO, USA; b Department of Surgery, Denver Health Medical Center, Denver, CO, USA; c Department of Medicine, University of Colorado at Denver, Health Sciences Center, Aurora, CO, USA; d Department of Biometrics, University of Colorado at Denver, Health Sciences Center, Aurora, CO, USA Abstract BACKGROUND: This study aimed to describe the natural history of delirium after major injury, to identify risk factors that predict the development of postinjury delirium, and to compare outcome measures in subjects with and without delirium. METHODS: A prospective study was performed on patients with an injury severity score of 8 or higher admitted to the trauma intensive care unit (ICU) of a level I trauma center. Patients underwent daily assessments for delirium with the Confusion Assessment Method-ICU. RESULTS: Sixty-nine patients (53 male) were enrolled. Delirium occurred in 41 (59%) subjects. Logistic regression found lower arrival Glasgow Coma Score (12  1.0 vs 15  .1; P  .01), increased blood transfusions (2.8  .7 vs .5  .3; P  .01), and higher multiple organ failure score (1.2  .2 vs .1  .1; P  .01) to be the strongest predictors for developing delirium. Outcome measures revealed subjects with delirium had longer hospital stays, longer ICU stays, and were more likely require postdischarge institutionalization. CONCLUSIONS: Delirium is common in the trauma ICU. Higher multiple organ failure score was the strongest predictor of postinjury delirium. © 2008 Published by Elsevier Inc. KEYWORDS: Delirium; Trauma; Postinjury; Geriatric Delirium is defined as a disturbance of consciousness char- acterized by a fluctuating mental status resulting from physi- ologic stress. 1 Most literature on delirium focuses on elderly hospitalized medical and surgical patients. Although trauma patients are, on the whole, a relatively young subgroup, it appears that delirium is common in injured patients admitted to the trauma intensive care unit (ICU). The incidence of delirium in mechanically ventilated trauma patients is 67%. 2 Delirium in the postinjury setting likely is owing to multiple causes including physiologic stress, comorbidi- ties, sedatives/analgesics, brain injury, and substance withdrawal. Poor outcomes are linked to delirium in hospi- talized patients including increased morbidity, longer hospital stay, and higher mortality. 3 Understanding risk factors related to the development of postinjury delirium will aid surgeons in identifying patients who need extra care to avoid the deleteri- ous outcomes that follow the development of delirium. The main objective of this study was to identify risk factors for the development of delirium after major injury. The specific aims were to describe the natural history of postinjury delirium, to identify clinical risk factors associ- * Corresponding author: Tel.: +1-303-724-2728; fax: +1-303-724- 2733. E-mail address: thomas.robinson@uchsc.edu Manuscript received May 2, 2008; revised manuscript July 8, 2008 0002-9610/$ - see front matter © 2008 Published by Elsevier Inc. doi:10.1016/j.amjsurg.2008.07.037 The American Journal of Surgery (2008) 196, 864 – 870