Risk factors for postoperative urinary retention following elective spine surgery: a meta-analysis

BACKGROUND CONTEXT: Limited studies have investigated risk factors for postoperative urinary retention (POUR) following elective spine surgery. Furthermore, some discrepancies have been found in the results of existing observational studies. PURPOSE: This study aimed to review the available literature on risk factors associated with POUR following elective spine surgery. STUDY DESIGN: A systematic review with meta-analysis was performed. PATIENT SAMPLE: A total of 31,251 patients (POUR=2,858, no POUR=28,393) were included in the meta-analysis. OUTCOME MEASURES: Demographics, type of elective spine surgery, country, definition of POUR, and potential risk factors for POUR were evaluated. METHODS: The Cochrane Library, Embase, and Medline electronic databases were searched to identify relevant studies. Binary outcomes were reported as odds ratio (OR). Weighted mean differences (WMD) or standardized mean differences (SMD), with 95% confidence intervals (CI), were used for meta-analysis of continuous outcomes. RESULTS: Eleven studies (2 prospective and 9 retrospective) were included in the analysis. Patients with POUR were older than those without POUR (WMD, 7.13; 95% CI, 4.50–9.76). Male patients were found to have an increased risk of POUR (OR, 1.31; 95% CI, 1.04–1.64). The following variables were also identified as significant risk factors for POUR: benign prostatic hyperplasia (BPH; OR, 3.79; 95% CI, 1.89–7.62), diabetes mellitus (DM; OR, 1.50; 95% CI, 1.17–1.93), and previous urinary tract infection (UTI; OR, 1.70; 95% CI, 1.28–2.24). Moreover, longer operative time (WMD, 19.88; 95% CI, 5.01–34.75) and increased intraoperative fluid support (SMD, 0.37; 95% CI, 0.23–0.52) were observed in patients with POUR. In contrast, spine surgical procedures involving fewer levels (OR, 0.75; 95% CI, 0.65–0.86), and ambulation on the same day as surgery (OR, 0.65; 95% CI, 0.52–0.81) were associated with a decreased risk of POUR. CONCLUSIONS: Based on our meta-analysis, older age, male gender, BPH, DM, and a history of UTI are risk factors for POUR following elective spine surgery. We also found that longer operative time and increased intravenous fluid support would increase the risk of POUR. Additionally, multi-level spine surgery may have a negative effect on postoperative voiding.