Predictors of Postoperative Delirium in Geriatric Patients Following Surgical Fixation of Fractures.

Abstract

Purpose: The purpose of this study was to investigate risk factors associated with postoperative delirium (POD) in patients following surgical fixation of fractures. Additionally, a frailty assessment tool previously associated with POD was evaluated to determine whether each component was significantly associated with POD. Methods: We performed a retrospective study of 608 patients aged ≥ 64 years admitted to the Massachusetts General Hospital for fractures. Medical, functional, and social data were collected at the initial assessment. A stepwise selection model was used to evaluate variables and create a model that predicted the risk of POD. Components of the FRAIL scale assessment were evaluated in an exploratory multivariable analysis to determine whether they were significantly associated with POD. Results: POD occurred in 92 (15.1%) patients. Patients with POD were more likely to be older (OR 1.05, 95% CI 1.01-1.09), and have higher FRAIL scale scores (OR 1.35, 95% CI 1.07-1.71) and positive MiniCog (score < 3) (OR 2.52, 95% CI 1.22-5.20). Female gender was protective for POD (OR 0.39, 95% CI 0.21-0.74). Of the FRAIL scale components, fatigue was a risk factor for POD and the ability to ambulate was protective (β= 0.28, 95% CI 0.0025-0.56 and β= -0.34, 95% CI -0.65, -0.03, respectively). Conclusions: In conclusion, older age, cognitive impairment, and frailty were risk factors for POD, whereas female gender was protective of POD in geriatric patients who underwent surgical repair of orthopedic fractures. MiniCog and FRAIL scale demonstrated predictive value in assessing patients’ risk factors for POD. The FRAIL scale components that were found to be significantly associated with POD risk were fatigue and the inability to ambulate.