Evaluation of Sacral Nerve Stimulation Device Revision and Explantation in a Single Center, Multidisciplinary Study

Abstract

Objective: This study aimed to determine the incidence and risk factors associated with revision or removal of a sacral nerve stimulation device for treatment of lower urinary tract dysfunction or fecal incontinence.

Materials and methods: This is a single-center multidisciplinary retrospective cohort study conducted at a university hospital from January 2013 through October 2017. Subjects who underwent successful sacral neuromodulation were identified via procedural codes. Clinical and demographic data regarding device revision or removal were extracted from the medical record. When testing differences between groups, t-test or Mann-Whitney U test was used to compare continuous variables. Categorical variables were compared by Chi-square test. Risk factors with a p value <0.2 in univariate investigation were included in the multivariate analysis. Logistic regression modeling was used to compare associations between risk factors and re-operation rates.

Results: Of the 219 subjects analyzed, 35 (16%) had revision or explantation of the sacral nerve stimulation device. Median time to re-operation was 164 days (interquartile range [IQR]: 29, 525). Subjects with device revised or explanted were younger, with a median age of 50 years vs. 62 years (p < 0.01) for those who did not undergo explantation. Patient demographics and co-morbidities were otherwise similar. Multivariate analysis identified age under 55 years (odds ratio [OR]: 2.51; 95% confidence interval [CI]: 1.18-5.33) as a significant risk factor. Our regression model showed that neither preimplantation diagnosis of chronic pain (OR: 0.60; 95% CI: 0.28-1.27) nor the specialty of the surgeon (OR 1.04; 95% CI 0.66-1.62) was associated with stimulation device revision or explantation.

Conclusions: This study found a 16% incidence of revision or explantation. Age under 55 years was identified as a significant risk factor. Our analysis did not find further demographic characteristics, co-morbid disorders, or behavioral diagnoses that were associated with revision or removal. Identification of risk factors may aid in patient selection for sacral nerve stimulation device implantation.

Keywords: fecal incontinence; lower urinary tract dysfunction; re-operation; risk factors; sacral neuromodulation.