Preoperative risk factors for postoperative delirium (POD) after urological surgery in the elderly

Abstract

The aim of this observational study was to investigate the occurrence of postoperative delirium (POD) in elderly patients undergoing urological surgery and to identify those factors associated with delirium. Ninety consecutive patients (81 males and 9 females; average age of 74.3 ± 0.40 years), undergoing urological surgery in University-Hospital Urological Clinic were selected. Personal, medical, cognitive and functional data, biochemical parameters, preoperative medications, conduct of surgery and anesthesia and details of hemodynamic control were collected as predictors of delirium. After surgery, the subjects were divided on the basis of delirium onset within a week observation period. Delirium was diagnosed by the Confusion Assessment Method. Delirium started the first post-operative day (2F; 6 M) and lasted 3.0 ± 0.8 days. Subjects with POD were significantly older, had a previous history of delirium, were more impaired in the instrumental activities of daily living and had poorer clock drawing test (CDT) score. Interestingly, a significantly greater number of hypotensive events were recorded during anesthesia. Age, cognitive and functional status, previous history of delirium and hypotensive episodes intrasurgery are the best predictor of POD in this setting. Our findings have implications in preventing delirium in elderly by an early and targeted evaluation.