Urinary retention after non-urological surgery is a common morbidity, with an incidence rate ranging between 2-78%, yet, it’s etiology and treatment approaches are still a matter of debate [1]. The aim of this study is to evaluate how urinary retention after non-urological surgery is being managed and determine the predictors of prognosis.

After Institutional Review Board approval, data were collected via electronic chart review at a single academic institution. Patients who were referred to the Urology clinic due to urinary retention after non-urological surgery between December 2014 and March 2021 were included. Patients with a history of lower urinary tract surgery were excluded. Demographical (age, gender) and surgical (duration of surgery, volume of intraoperative intravenous fluid infusion, operative positioning, type of anesthesia, use of patient controlled anesthesia) parameters were recorded. Presence of comorbidities (hypertension [HT], diabetes mellitus [DM]), body mass index (BMI), American Society of Anesthesiologist (ASA) score, type of non-urological surgery, recommended treatment with regards to urinary retention, and the final urinary condition of the patients were reviewed. 
In all patients, urethral catheter was kept in-situ for at least 5-7 days after urinary retention. In male patients, treatment with an alpha-adrenergic antagonist was initiated during this period. In case of persistent urinary retention after urethral catheter removal, clean intermittent catheterization (CIC) was recommended. In the first month follow-up visit, invasive urodynamic study [UDS] (filling cystometry and pressure-flow study) was recommended if the patient’s post-void residual urine volume was above 150 ml.
Statistical calculations were done with Student’s t test or Mann-Whitney U test for continuous variables and chi-squared test or Fisher’s exact test for categorical variables.

A total of 82 patients were included. The median age of the patients was 65 (24-90) years. Sixty-three patients were male and 19 were female. Urinary retention was detected after 33 rectal, 11 spinal, 8 cardiovascular, 6 thoracic, 6 orthopedic, 4 gynecological, 2 cranial, 2 retroperitoneal, 1 otolaryngological, and 9 other general surgical procedures (Table 1). The median operative duration was 180 (50-900) minutes. In 65 patients (79.2%), spontaneous urination returned with conservative management (urethral catheter ± alpha blocker) (Group 1). Seventeen patients (20.8%) required CIC due to persistent urinary retention (Group 2). The number of male and female patients in the CIC group was 9 (9/63) and 8 (8/19), respectively (p<0.05). The median follow-up duration was 31 (1-108) months.
Despite being recommended to 17 patients, invasive UDS could be performed only in 5 patients. None of them exhibited detrusor contractions during the pressure-flow study. The median maximum detrusor pressure was 20 (17-43) cmH2O. There were no statistically significant differences between the two groups in terms of patient age, presence of HT or DM, ASA score, BMI, duration of surgery, the amount of intraoperative intravenous fluid administration, position at operation, type of anesthesia, or presence of PCA. 
In Group 2, majority underwent colectomy due to malignancy (p>0.05) Table 2. At a median follow-up of 31 months, only 4 patients (4/17, 23.5%) stopped doing CIC and endorsed return of spontaneous micturition (3/4: colon cancer surgeries 1/4: spinal surgery).

Our results revealed that spontaneous urination returned in 79.2% of the patients only with conservative management, which is higher than the rate reported in the literature (65-70%) [2]. In our series, 42.1% of female patients required CIC, while in males this rate was 14.2%. In the literature, impact of gender on urinary retention was controversial. Similar to our data, Toyonaga et al. reported female gender as an independent risk factor for urinary retention after anorectal surgeries in a multivariate analysis[3]. Rates of epidural anesthesia and PCA were higher in Group 2. Of note, rate of DM was higher in patients who spontaneously urinated after conversative management than who needed long-term CIC. Majority of the cases who needed long-term CIC, underwent colectomy due to malignancy. To the best of our knowledge, our median follow-up duration of 31 months is one of the longest reported in the literature.

Majority of the patients who developed urinary retention after non-urological surgery regained spontaneous micturition with conservative management only, without requiring invasive diagnostic tests or therapeutic interventions. Female gender, colonic surgery due to malignancy, epidural anesthesia and PCA had a negative influence on resolution of urinary retention after non-urological surgeries. Further studies with larger number of patients and prospective design could provide insights into the natural history and management strategy of this prevalent urological morbidity with an unclear etiology.

Baldini, G., et al., Postoperative urinary retention: anesthetic and perioperative considerations. Anesthesiology, 2009. 110(5): p. 1139-57.
Lee, K.S., et al., Predictors of Successful Trial without Catheter for Postoperative Urinary Retention Following Non-Urological Surgery. Int Neurourol J, 2011. 15(3): p. 158-65.
Toyonaga, T., et al., Postoperative urinary retention after surgery for benign anorectal disease: potential risk factors and strategy for prevention. Int J Colorectal Dis, 2006. 21(7): p. 676-82.