Use of Antibacterial Envelopes for Prevention of Infection in Neuromodulation Implantable Pulse Generators

Antibiotic-impregnated envelopes reduce the rate of surgical site infection in deep brain stimulation pulse generators: a comparative study

BACKGROUND AND PURPOSE

Deep brain stimulation (DBS) is a surgical procedure that has been used to treat a variety of neurological disorders including Parkinson's disease, essential tremor, and dystonia. While DBS is generally considered safe and effective, surgical site infections (SSIs) are a potential complication that can lead to significant morbidity and mortality. Our objective was to investigate the use of antibiotic-impregnated envelopes (AIEs) encasing implantable pulse generators (IPGs) to reduce the rate of infection at IPG sites and the costs.

METHODS

We conducted a retrospective analysis at a single center encompassing all procedures involving the placement of Implantable Pulse Generators (IPG), including both initial insertions and replacement surgeries. The study period spanned from January 2017 to May 2024. Starting in 2020, the routine utilization of AIE became standard practice at our institute for both primary DBS implantation and IPG replacements. Surgical techniques remained consistent, pre- and post-operative antibiotic protocols were standardized throughout the study period and all cases were undertaken by a single surgeon.

RESULTS

178 patients were included and the overall incidence of IPG SSIs was found to be 1.7% (1 infection in 58 patients; 20 primary IPG/38 IPG replacements) among those who received an AIE compared to 5% (6 infections in 120 patients; 36 primary IPG/84 replacement IPG) in patients where no AIE was utilized. This resulted in an odds ratio for infection that was 2.9 times higher in the absence of AIE. The decrease in infection rates was observed in both primary and replacement IPG implants. Notably, over 80% of patients with IPG infection required surgical intervention. The use of AIE further resulted in significant cost savings.

CONCLUSION

To our knowledge, this is the largest series reporting the efficacy of Antibiotic impregnated envelope (AIE) in modifying infection rates associated with both initial and replacement Deep Brain Stimulation (DBS) Implantable Pulse Generators (IPGs). The implementation of AIEs led to a decrease in the occurrence of IPG-related infections, observed across both primary implantations and replacement surgeries, with associated economic benefits.

Do Antibiotic-Impregnated Envelopes Prevent Deep Brain Stimulation Implantable Pulse Generator Infections? A Prospective Cohort Study

INTRODUCTION

Infection after deep brain stimulation (DBS) implanted pulse generator (IPG) replacement is uncommon but when it occurs can cause significant clinical morbidity, often resulting in partial or complete DBS system removal. An antibiotic absorbable envelope developed for cardiac implantable electronic devices (IEDs), which releases minocycline and rifampicin for a minimum of 7 days, was shown in the WRAP-IT study to reduce cardiac IED infections for high-risk cardiac patients. We aimed to assess whether placing an IPG in the same antibiotic envelope at the time of IPG replacement reduced the IPG infection rate.

METHODS

Following institutional ethics approval (UnitingCare HREC), patients scheduled for IPG change due to impending battery depletion were prospectively randomised to receive IPG replacement with or without an antibiotic envelope. Patients with a past history of DBS system infection were excluded. Patients underwent surgery with standard aseptic neurosurgical technique [J Neurol Sci. 2017;383:135-41]. Subsequent infection requiring antibiotic therapy and/or IPG removal or revision was recorded.

RESULTS

A total of 427 consecutive patients were randomised from 2018 to 2021 and followed for a minimum of 12 months. No patients were lost to follow-up. At the time of IPG replacement, 200 patients received antibiotic envelope (54 female, 146 male, mean age 72 years), and 227 did not (43 female, 184 male, mean age 71 years). The two groups were homogenous for risk factors of infection. The IPG replacement infection rate was 2.1% (9/427). There were six infections, which required antibiotic therapy and/or IPG removal, in the antibiotic envelope group (6/200) and three in the non-envelope group (3/227) (p = 0.66).

CONCLUSION

This prospective randomised study did not find that an antibiotic envelope reduced the IPG infection rate in our 427 patients undergoing routine DBS IPG replacement. Further research to reduce IPG revisions and infections in a cost-effective manner is required.

Assessing the effectiveness of antimicrobial pouch use for infection prevention in sacral neuromodulation

INTRODUCTION AND HYPOTHESIS

Sacral neuromodulation (SNM) is a commonly performed procedure for various conditions. Infection rates range as high as 10% and often require operative explantation with resultant increased cost and morbidity. Pouches impregnated with antibiotic have been utilized in cardiovascular procedures with decreasing infectious complications. TYRX is an antibiotic pouch utilizing minocycline and rifampin manufactured by Medtronic. The objective of this study is to investigate the utility of antimicrobial pouches for patients undergoing SNM.

METHODS

We retrospectively analyzed our patients undergoing SNM using an antimicrobial pouch and compared them with a historic cohort. Additional variables of interest included post-operative infection, diagnosis of diabetes, weight, and revision case or virgin implant.

RESULTS

A total of 170 cases were identified, ranging from March 2017 to November 2022. Overall infection rate was 2.9% with 0 in the antimicrobial pouch cohort (0%) versus 5 in the historic cohort (5.5%; p = 0.04). Groups were similar in terms of body habitus. The group receiving an antimicrobial pouch was noted to be older with a higher percentage of female patients. 85 patients received an antimicrobial pouch and 85 did not. Of the infections, 4 occurred in revision cases (6.9%) and 1 in a virgin implant (0.9%; p = 0.03). No difference was noted in infection rate with regard to a diagnosis of diabetes or body habitus.

CONCLUSION

The use of antimicrobial pouches in SNM is associated with a decreased rate of infectious complications. Revision cases displayed a higher rate of infectious complications.