Incidence and factors associated with postoperative delirium in patients undergoing transurethral resection of bladder tumor

Background Postoperative delirium is an important complication after surgery, including urological surgery. This study evaluated the incidence of postoperative delirium and its associated factors after transurethral resection of bladder tumor in adult patients. Methods Patients aged >= 20 years who underwent elective transurethral resection of bladder tumor under general anesthesia from April 2016 to November 2020 were included. Patient demographic and intraoperative data, including the administration of 5-aminolevulinic acid and hypotension, defined as a mean arterial pressure value < 60 mmHg, were evaluated. The primary outcome was the incidence of postoperative delirium assessed using a chart-based method. The factors associated with postoperative delirium were explored using multiple logistic regression analysis. Postoperative lengths of stay between patients with and without postoperative delirium were compared using the Mann-Whitney U-test. Results Of 324 eligible patients with a median age of 76, 26 patients experienced postoperative delirium, with an incidence rate of 8.0% (95% confidence interval, 5.06-10.9). Age (odds ratio 1.13, 95% confidence interval 1.05-1.22, p = 0.001) and body mass index (odds ratio 0.83, 95% confidence interval 0.71-0.97, p = 0.02) were associated with postoperative delirium. Postoperative length of stay between patients with or without postoperative delirium was not significantly different (6 vs 6 days, p = 0.18). Conclusions The incidence of postoperative delirium after transurethral resection of bladder tumor under general anesthesia in this study was 8.0%. Older age and low body mass index were associated with development of postoperative delirium.