Risk factors for postoperative urinary retention in patients underwent surgery for benign anorectal diseases: a nested case–control study

Postoperative urinary retention (POUR) is a common complication of anorectal surgery. This study was to determine the incidence of POUR in anorectal surgery for benign anorectal diseases, identify its risk factors, and establish a nomogram for prediction of POUR. A nested case–control study was conducted. The clinical data of patients were collected, and the incidence of POUR was analyzed. Univariate analysis was used to identify the risk factors associated with POUR, and multivariate logistic regression analysis was used to determine independent risk factors for POUR. A nomogram for the preoperative prediction of POUR using a logistic regression model was developed (n = 609). The incidence of POUR after anorectal surgery for benign anorectal diseases was 19.05%. The independent risk factors for POUR were: female (P = 0.007); male with benign prostatic hyperplasia (BPH) (P = 0.001); postoperative visual analogue scale (VAS) score > 6 (P = 0.002); patient-controlled epidural analgesia (PCEA) (P = 0.016); and a surgery time > 30 min (P = 0.039). In the nomogram, BPH is the most important factor affecting the occurrence of POUR, followed by a postoperative VAS score > 6, PCEA, surgery time > 30 min, and sex has the least influence. For patients undergoing anorectal surgery for benign anorectal diseases, preventive measures can be taken to reduce the risk of POUR, taking into account the following risk factors: female or male with BPH, severe postoperative pain, PCEA, and surgery time > 30 min. Furthermore, we developed and validated an easy-to-use nomogram for preoperative prediction of POUR in anorectal surgery for benign anorectal diseases. China Clinical Trial Registry: ChiCTR2000039684, 05/11/2020.