Effect of General Versus Spinal Anesthesia on Postoperative Delirium and Early Cognitive Dysfunction in Elderly Patients

Background: Postoperative cognitive dysfunction (POCD) and delirium arecommonin the elderly patients, given the controversial results of previous studies about the impact of anesthesia type on the occurrence of these complications. Objectives: This study was planned to compare the effects of general and spinal anesthesia on the prevalence of POCDand delirium. Methods: A single-blind non-randomized clinical trial. Setting was in two academic hospitals. Ninety-four patients over 50 years old scheduled for hip fracture fixation. Patients were divided into two groups to receive either general (GA) or spinal (SA) anesthesia. Both Mini-Mental State examination (MMSE) andWechsler tests were used before the operation and 3 times postoperatively to assess the cognitive function and detect early POCD. The DSM-IV criteria were also used for the diagnosis of delirium. The incidence of delirium and POCD and their precipitating factors were compared between the two groups. Results: Ninety-four patients with a mean age of 67.12 years were studied. The overall prevalence of POCD and delirium was 17.02%; however, it was significantly higher in the GA group rather than the SA group, 29.7%, and 4.25%, respectively (P < 0.001). There was a significant relationship between age (P = 0.048), ASA class (P = 0.034), and educational level with the incidence of POCD, meaning that the probability of developing cognitive impairment decreases with patients’ higher level of education and lower ASA-physical status. Also, the rate of POCD in men was significantly higher than in women (P = 0.026). Conclusions: The finding of this study showed that, if there is no specific contraindication, neuraxial anesthesia may be preferred over general anesthesia in elderly patients.