Risk factors for delirium after intertrochanteric fracture surgery in the elderly

Abstract

Objective To investigate the risk factors for delirium after intertrochanteric fracture surgery in the elderly. Methods The data of 423 elderly patients with femoral intertrochanteric fracture were retrospectively analyzed who had been treated by closed reduction and internal fixation with proximal femoral nail antirotation (PFNA) at Department of Orthopedics, The Second Central Hospital of Baoding from December 2010 to April 2018. They were 205 males and 218 females, aged from 70 to 98 years (mean, 78.6 years). By AO classification, 239 fractures were type 31-A1, 141 ones type 31-A2, and 43 ones type 31-A3. Of them, 362 were complicated with disease of internal medicine. The interval from injury to surgery ranged from 4 to 72 hours with an average of 46.6 hours. The incidence of postoperative delirium was recorded. The risk factors were screened by univariate analysis from the hidden blood loss, gender, age, body mass index, complications, anesthesia method, preoperative preparation time and electrolyte disturbance; multivariate logistic regression analysis was used to determine the independent risk factors from the factors with P< 0.05. Results Post-operative delirium occurred in 49 of the 423 patients (11.58%) (29 cases on the first postoperative day and 20 ones on the second postoperative day). It was not observed in the other 374 (88.42%) patients. Univariate analysis showed significant differences in the interval from injury to surgery, hidden blood loss and electrolyte disturbance between the patients with and without postoperative delirium (P 48 hours (OR=3.386, 95% CI: 1.362 to 6.638), hidden blood loss>600 mL (OR=10.292, 95% CI: 1.244 to 35.091) and electrolyte disturbance (OR=4.157, 95% CI: 1.595 to 7.626) were the independent risk factors for postoperative delirium in elderly patients with intertrochanteric fracture. Conclusion Long preoperative preparation, a large amount of hidden blood loss and postoperative electrolyte disturbance may be the risk factors for post-operative delirium in elderly patients with intertrochanteric fracture afterinternal fixation. Key words: Hip fractures; Latent blood loss; Delirium; Risk factors; Aged