Predictors of success in hypoglossal nerve stimulator implantation for obstructive sleep apnea

OBJECTIVE: Current guidelines for hypoglossal nerve stimulator (HGNS) implantation eligibility include drug-induced sleep endoscopy (DISE) findings and other patient characteristics but lead to highly variable rates of surgical success across institutions. Our objective was to determine whether additional factors seen on preoperative evaluation could be used as predictors of surgical success. STUDY DESIGN: Retrospective chart review. SETTING: Single-institution academic tertiary care medical center. SUBJECTS: and Methods:This study included patients with obstructive sleep apnea (OSA) who underwent HGNS implantation between 2015 and 2018. Surgical success was defined as a postoperative apnea-hypopnea index (AHI) of less than 20 events per hour and an AHI reduction of at least 50%. Preoperative polysomnogram (PSG) results, DISE findings, and physical parameters were compared between surgical successes and failures. RESULTS: A total of 68 patients were included in the analysis. The overall surgical success rate was 79.4% (54/68). Elevated preoperative AHI was associated with an increased likelihood of treatment failure, with an AHI of (36.9 ± 16.8) events/hour in the success group compared to (49.4 ± 19.6) events/hour in the failure group (P = 0.05). Patients observed to have partial lateral oropharyngeal collapse on DISE was more frequently associated with the treatment failure group than in the success group (P = 0.04). CONCLUSION: Patients who underwent HGNS implantation overall had a very high treatment response rate at our institution. Factors that may predispose patients to surgical failure included the presence of lateral oropharyngeal collapse and a significantly elevated preoperative AHI. These should be considered when determining surgical candidacy for HGNS implantation.