Prophylactic Vancomycin Leads to Fewer Device Removals in Sacral Neuromodulation

Objectives: Sacral neuromodulation (SNM) for bladder and bowel dysfunction requires removal for infectious complications in 3-11% of patients. We studied whether preoperative antibiotic choice impacted device removal rates.

Methods: Using the Health Facts® Database, representing more than 750 hospitals, we included female patients who underwent SNM implantation between 2010 and 2018. Exclusion criteria included incomplete records for both stages, an unlikely antibiotic for infection prophylaxis (i.e. Macrobid), or a combination of antibiotics. Univariate and multivariate logistic regression was performed to identify factors associated with device removal. 35 separate comorbidities were evaluated and those with p< 0.2 on univariate analysis were included in the multivariate analysis. We decided a priori to include prophylactic antibiotic choice in the final model, but it ultimately also met inclusion criteria with p=0.17.

Results: 1,433 patients were included in our final analysis, of which 170 (11.9%) had device removal (Table 1). Subjects were 70.0 ± 14.9 years old, predominantly Caucasian (90.0%), treated in an urban hospital (94.1%), and married (54.2%). 11.8% were obese, and 18.0% smoked. There were no significant differences between the removal and non-removal cohorts apart from more urinary incontinence in the non-removal group (table 1, p = 0.003). 52.3% received a 1st gen cephalosporin (CPSN), 7.4% 2nd or 3rd gen CPSNs, 9.1% vancomycin, 13.4% aminoglycoside, 4.6% clindamycin, and 13.3% a fluoroquinolone. Multivariate logistic regression analysis in table 2 revealed fewer removals with vancomycin compared to first generation CPSN (OR=2.5, 95% CI [1.1,5.4]); fluoroquinolone (OR=2.8, [1.2, 6.7]); or second/third generation CPSNs (OR=2.6, [1.0, 6.7]).

LEGENDS:
TABLE 1: Demographics represented as n (%) unless otherwise specified.; SD = standard deviation; Differences between study groups determined using Fisher’s exact tests (categorical) and t-tests (numerical)
TABLE 2: *Only variables with pre-defined significance of p < 0.2 in univariate regression analysis were included in multivariate regression analysis.; **Compared to vancomycin.; OR = odds ratio.; CI = confidence interval.

Conclusions: Vancomycin was a superior prophylactic antibiotic compared to other commonly used antibiotics to prevent SNM device removal. While a prospective trial would help confirm this benefit, low device removal rates overall may make this impractical.