Introduction: Deep brain stimulation (DBS) is increasingly being used as an effective treatment for a variety of neurological disorders. Complications and/or malfunction of internal pulse generators (IPGs) for DBS are estimated to occur in 12.9% of patients (1). Little is known about the risk of surgical procedures for implantation, revision, replacement, and removal of IPGs. Therefore, our objective was to investigate the prevalence of and risk factors for postoperative complications following IPG-related procedures within the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP).

Methods: Patients undergoing surgery performed by neurosurgeons for implantation, revision, replacement, or removal of cranial IPGs (CPT codes: 61885, 61886, 61888) from 2005 to 2015 were extracted from the ACS-NSQIP. Cases with concurrent surgery for DBS electrode implantation were excluded from this study. The prevalence of postoperative complications was determined. Multivariable logistic regression was used to identify demographic, comorbid, and perioperative characteristics associated with at least one 30-day complication.

Results: A total of 2,025 cases of IPG-related surgery were identified. Of these, there were 61 (3.01%) cases with at least one complication and 5 (0.25%) cases with mortality. The most common complications were reoperation (1.48%) and superficial surgical site infection (0.59%). In multivariable logistic regression models, tobacco use (Odds Ratio [OR]: 2.54; 95% Confidence Interval [CI]: 1.22-5.31; p=0.013), wound class II-IV (OR: 3.53; 95% CI: 1.40-8.93; p=0.008), and duration of surgery in hours (OR: 1.28; 95% CI: 1.08-1.52; p=0.004) were significantly associated with higher odds of at least one complication.

Conclusions: Postoperative complications following implantation, revision, replacement, and/or removal of IPGs are relatively rare (3.01%). Tobacco use, contaminated wound classification, and longer duration of surgery were risk factors for any complication. These estimates and risk factors should be considered in the long-term management of patients with DBS for neurological disorders.

Patient Care: This study highlights the prevalence of postoperative complications following procedures for implantation, revision, replacement, and removal of internal pulse generators for deep brain stimulation. Our findings demonstrate that complications are rare and risk factors for complications include tobacco use, contaminated wound classification, and longer duration of surgery. These results will help improve patient care by informing both clinicians and patients alike to the risks related to procedures that may arise during long-term therapy with deep brain stimulation.

Learning Objectives: At the conclusion of this session, participants should be able to: 1) describe demographic, comorbid, and perioperative characteristics of patients undergoing internal pulse generator-related surgery; 2) estimate the prevalence of postoperative complications following internal pulse generator-related surgery; and 3) identify risk factors for postoperative complications following internal pulse generator-related surgery.

References: (1) K. E. Lyons, S. B. Wilkinson, J. Overman, and R. Pahwa, “Surgical and hardware complications of subthalamic stimulation: a series of 160 procedures,” Neurology, vol. 63, no. 4, pp. 612–616, 2004.