Postoperative prophylactic antibiotics for retropubic mid-urethral slings

Objectives and hypothesis: The primary objective is to measure the difference in urinary tract infection (UTI) rates within 6 weeks of placement of a retropubic mid-urethral sling (RMUS) in the setting of various postoperative prophylactic antibiotic regimens. UTI rates were measured by antibiotic prescriptions to treat UTI and/or culture. Secondary aims included determining risk factors for postoperative UTI.

Methods: A retrospective chart review from 2014 to 2016 was performed at Baylor Scott and White Medical Center-Temple for CPT code 57288. Univariate comparisons were performed using chi-square and Student's t-test. Logistic regression analysis was performed for UTI risk factors with univariate p values ≤ 0.1.

Results: One hundred twelve subjects were included. Seventeen (15%) were treated for postoperative UTI. Postoperative prophylactic antibiotics included trimethoprim (39.3%), nitrofurantoin (31.3%), trimethoprim-sulfamethoxazole (5.4%), ciprofloxacin (2.7%), and cephalexin (1.8%). Ninety subjects were prescribed postoperative prophylactic antibiotics (80.4%). The postoperative UTI rate was not significantly different between those who were prescribed postoperative prophylactic antibiotics (16%) and those who were not (14%). None of the treatments showed a significant difference on postoperative UTI rate compared to no treatment. Significant risk factors for UTI included catheterization past postoperative day 1 (OR 6.4, 95% CI 1.7 - 23.8; p = 0.006).

Conclusions: There was no significant difference in postoperative UTI rate in the group without postoperative prophylactic antibiotics compared to those who did receive it. Catheterization past postoperative day 1 was significantly associated with postoperative UTI. However, definitive conclusions are limited by a lack of power.