Evaluation of delirium frequency and factors affecting it in postanesthesia care unit

Postoperative delirium (POD) is a common but often underrecognized complication after surgery and is associated with increased morbidity and prolonged hospitalization. This study aimed to determine the incidence of POD in the postanesthesia care unit (PACU) and to identify perioperative factors independently associated with its development. This prospective observational study included adult surgical patients admitted to the PACU between August 2021 and January 2023. Delirium assessments were performed daily using the confusion assessment method for the intensive care unit, nursing delirium screening scale, and intensive care delirium screening checklist after extubation and discontinuation of continuous sedative infusions. Demographic characteristics, comorbidities, intraoperative variables, and postoperative biochemical parameters were recorded. Independent predictors of POD were determined using multivariable logistic regression. A total of 314 patients were analyzed, and POD occurred in 22.6% of cases, predominantly hypoactive in subtype (76%). Independent predictors included age ≥65 years (odds ratio [OR]: 3.08; 95% confidence interval [CI]: 1.10 to 8.63; P = .032), higher PACU pain scores (OR: 1.28; 95% CI: 1.03 to 1.59; P = .025), lower hematocrit (OR: 0.89; 95% CI: 0.82 to 0.98; P = .014), reduced glomerular filtration rate (OR: 0.98; 95% CI: 0.97 to 1.00; P = .014), and longer fentanyl infusion duration (OR: 1.09; 95% CI: 1.01 to 1.17; P = .025). Patients with delirium had significantly longer PACU stays, higher intensive care unit admission rates, prolonged hospitalizations, and increased postoperative complications and mortality. POD is frequent among PACU patients and is strongly associated with advanced age, impaired renal function, anemia, severe postoperative pain, and prolonged opioid exposure. Implementation of early structured screening and optimization of modifiable perioperative risk factors may help reduce delirium incidence and improve postoperative outcomes.