Hypoglossal Nerve Stimulation and Cardiovascular Outcomes for Patients With Obstructive Sleep Apnea: A Randomized Clinical Trial.

Importance: Sham-controlled trials are needed to characterize the effect of hypoglossal nerve stimulation (HGNS) therapy on cardiovascular end points in patients with moderate-severe obstructive sleep apnea (OSA). Objective: To determine the effect of therapeutic levels of HGNS, compared to sham levels, on blood pressure, sympathetic activity, and vascular function. Design, Setting, and Participants: This double-blind, sham-controlled, randomized crossover therapy trial was conducted from 2018 to 2022 at 3 separate academic medical centers. Adult patients with OSA who already had an HGNS device implanted and were adherent and clinically optimized to HGNS therapy were included. Participants who had fallen asleep while driving within 1 year prior to HGNS implantation were excluded from the trial. Data analysis was performed from January to September 2022. Interventions: Participants underwent a 4-week period of active HGNS therapy and a 4-week period of sham HGNS therapy in a randomized order. Each 4-week period concluded with collection of 24-hour ambulatory blood pressure monitoring (ABPM), pre-ejection period (PEP), and flow-mediated dilation (FMD) values. Main Outcomes and Measures: The change in mean 24-hour systolic blood pressure was the primary outcome, with other ABPM end points exploratory, and PEP and FMD were cosecondary end points. Results: Participants (n = 60) were older (mean [SD] age, 67.3 [9.9] years), overweight (mean [SD] body mass index, calculated as weight in kilograms divided by height in meters squared, 28.7 [4.6]), predominantly male (38 [63%]), and had severe OSA at baseline (mean [SD] apnea-hypopnea index, 33.1 [14.9] events/h). There were no differences observed between active and sham therapy in 24-hour systolic blood pressure (mean change on active therapy, -0.18 [95% CI, -2.21 to 1.84] mm Hg), PEP (mean change on active therapy, 0.11 [95% CI, -5.43 to 5.66] milliseconds), or FMD (mean change on active therapy, -0.17% [95% CI, -1.88% to 1.54%]). Larger differences between active and sham therapy were observed in a per-protocol analysis set (n = 20) defined as experiencing at least a 50% reduction in apnea-hypopnea index between sham and active treatment. Conclusions and Relevance: In this sham-controlled HGNS randomized clinical trial, mean 24-hour systolic blood pressure and other cardiovascular measures were not significantly different between sham and active HGNS therapy. Several methodologic lessons can be gleaned to inform future HGNS randomized clinical trials. Trial Registration: ClinicalTrials.gov Identifier: NCT03359096.

Pneumothorax during upper airway stimulation: Does experience make a difference?

OBJECTIVES: Upper airway stimulation is a treatment option for select patients with obstructive sleep apnea. Pneumothorax may occur with UAS implantation during placement of the respiratory sensor. This study aims to evaluate the incidence of pneumothorax during UAS device placement. We hypothesize that sleep surgeons with high implantation volumes experience lower rates of pneumothorax compared to the general population of surgeons. METHODS: We also aim to describe management of pneumothorax when it does occur. The incidence of pneumothorax during UAS implantation among the general population of surgeons was assessed using the TriNetX Research Network. Additionally, a select group of Otolaryngologist sleep surgeons with a high UAS implantation volume were surveyed regarding experiences with UAS related pneumothoraces. RESULTS: 8 pneumothoraces occurred among 3823 UAS procedures in the surveyed otolaryngologist sleep surgeon population. 4 required chest tube insertion. Among the general population cohort, 42 of 1233 patients developed pneumothorax after UAS implantation. The rates of pneumothorax between the otolaryngologist sleep surgeon cohort and general population of surgeons cohort were 0.21 % and 3.4 % respectively (p < 0.00001). CONCLUSION: Pneumothorax rarely occurs during UAS implantation. Surgeons with higher implantation volumes showed a lower incidence of pneumothorax. Pneumothorax management is dependent on patient stability, perioperative setting, and degree of injury. The use of needle decompression, chest tube placement, and suture placement also vary with clinical scenario.

Two-Incision Approach for Hypoglossal Nerve Stimulator Placement: A Single Institution Assessment.

OBJECTIVE(S): Upper airway stimulator (UAS) placement is a treatment for obstructive sleep apnea (OSA) with few complications and low morbidity. UAS placement has traditionally been performed using a three-incision approach, however, it has been implanted using a two-incision approach. This approach could significantly decrease operation time without a difference in postoperative complications, demonstrating its safety and feasibility for UAS placement. The objective was to assess operative time and complication rate in the two-incision approach for UAS placement compared to the three-incision approach. STUDY DESIGN: Retrospectively reviewed. METHODS: Patients who underwent UAS placement using the two- or three-incision approach at a single academic institution from November 2014 to June 2021 were retrospectively reviewed. The two-incision approach did not include the incision at the mid-axillary line. Main outcome measures included operation time and complication rates. RESULTS: Three-hundred forty-eight patients underwent UAS placement. The three-incision approach demonstrated an average operation time of 143.3 minutes whereas the two-incision approach averaged 129.4 minutes (P < .001). There was no significant difference in rate of postoperative complications between the two- and three-incision cohorts including pneumothorax (0% vs. 0.4%, P > .99), patient-reported discomfort (5.6% vs. 6.5%, P > .99), activity restriction (0% vs. 1.4%, P > .50), and incisional pain (0.0% vs. 1.0%, P > .99). No patients experienced incision site bleeding or infection. The two-incision approach was associated with decreased rate of revision surgery (0.0% vs. 5.4%, P = .048). CONCLUSION: The UAS two-incision approach proved to have a significantly shorter operative time without an increase in complications as compared to the three-incision approach. This approach is a safe and feasible option. LEVEL OF EVIDENCE: 3 Laryngoscope, 132:1687-1691, 2022.

Hypoglossal Nerve Stimulation Usage by Therapy Nonresponders.

OBJECTIVE: The purpose of this study is to examine differences in therapy usage and outcomes of therapy between responder (R) and nonresponder (NR) groups in an international, multicenter prospective registry of patients undergoing hypoglossal nerve stimulation for obstructive sleep apnea (OSA). STUDY DESIGN: Database analysis (level III). SETTING: International, multicenter registry. METHODS: The studied registry prospectively collects data pre- and postimplantation, including sleep parameters, Epworth score, patient experience, and safety questions, over the course of 12 months. Patients are defined as a "responder" based on Sher criteria, which require a final apnea-hypopnea index (AHI) of ≤20 and a final AHI reduction of >50% at their 12-month follow-up. RESULTS: Overall, there were 497 (69%) R and 220 (31%) NR. Most patients in both groups experienced improvement in quality of life following implantation (96% of R; 77% of NR) with reductions in oxygen desaturation index and Epworth score. At final follow-up, the R group demonstrated significantly better adherence to recommended therapy (>4 hours/night) (P = .001), average hours of nightly use (P = .001), final Epworth scores (P = .001), and degree of subjective improvement (P < .001). CONCLUSION: Patients classified as NR to upper airway stimulation continue to use therapy with improvement in percent time of sleep with O2 <90%, reduction in daytime sleepiness, and improvement in quality of life. Therefore, ongoing usage of the device should be encouraged in NR patients who note improvement while integrating additional strategies to lower the long-term effects of OSA.

Impact of Body Mass Index and Discomfort on Upper Airway Stimulation: ADHERE Registry 2020 Update.

OBJECTIVES/HYPOTHESIS: To provide the ADHERE registry Upper Airway Stimulation (UAS) outcomes update, including analyses grouped by body mass index (BMI) and therapy discomfort. STUDY DESIGN: Prospective observational study. METHODS: ADHERE captures UAS outcomes including apnea-hypopnea index (AHI), Epworth sleepiness scale (ESS), therapy usage, patient satisfaction, clinician assessment, and safety over a 1-year period. BMI ≤32 kg/m2 (BMI32 ) and 32 < BMI ≤35 kg/m2 (BMI35 ) group outcomes were examined. RESULTS: One thousand eight hundred forty-nine patients enrolled in ADHERE, 1,019 reached final visit, 843 completed the visit. Significant changes in AHI (-20.9, P < .0001) and ESS (- 4.4, P < .0001) were demonstrated. Mean therapy usage was 5.6 ± 2.2 hr/day. Significant therapy use difference was present in patients with reported discomfort versus no discomfort (4.9 ± 2.5 vs. 5.7 ± 2.1 hr/day, P = .01). Patients with discomfort had higher final visit mean AHI versus without discomfort (18.9 ± 18.5 vs. 13.5 ± 13.7 events/hr, P = .01). Changes in AHI and ESS were not significantly different. Serious adverse events reported in 2.3% of patients. Device revision rate was 1.9%. Surgical success was less likely in BMI35 versus BMI32 patients (59.8% vs. 72.2%, P = .02). There was a significant therapy use difference: 5.8 ± 2.0 hr/day in BMI32 versus 5.2 ± 2.2 hr/day in BMI35 (P = .028). CONCLUSIONS: Data from ADHERE demonstrate high efficacy rates for UAS. Although surgical response rate differs between BMI32 and BMI35 patient groups, the AHI and ESS reduction is similar. Discomfort affects therapy adherence and efficacy. Thus, proper therapy settings adjustment to ensure comfort is imperative to improve outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2616-2624, 2021.

Improving outcomes of hypoglossal nerve stimulation therapy: current practice, future directions, and research gaps. Proceedings of the 2019 International Sleep Surgery Society Research Forum.

Hypoglossal nerve stimulation (HGNS) has evolved as a novel and effective therapy for patients with moderate-to-severe obstructive sleep apnea. Despite positive published outcomes of HGNS, there exist uncertainties regarding proper patient selection, surgical technique, and the reporting of outcomes and individual factors that impact therapy effectiveness. According to current guidelines, this therapy is indicated for select patients, and recommendations are based on the Stimulation Therapy for Apnea Reduction or STAR trial. Ongoing research and physician experiences continuously improve methods to optimize the therapy. An understanding of the way in which airway anatomy, obstructive sleep apnea phenotypes, individual health status, psychological conditions, and comorbid sleep disorders influence the effectiveness of HGNS is essential to improve outcomes and expand therapy indications. This article presents discussions on current evidence, future directions, and research gaps for HGNS therapy from the 10th International Surgical Sleep Society expert research panel. CITATION: Suurna MV, Jacobowitz O, Chang J, et al. Improving outcomes of hypoglossal nerve stimulation therapy: current practice, future directions and research gaps. Proceedings of the 2019 International Sleep Surgery Society Research Forum. J Clin Sleep Med. 2021;17(12):2477-2487.

Upper airway stimulation: Fewer complications, ED presentations, readmissions, and increased surgical success.

OBJECTIVES: Evaluate the rate of complications, readmissions, emergency department presentations, and surgical success rates amongst three standard surgical treatment options for obstructive sleep apnea: upper airway stimulation, transoral robotic surgery, and expansion sphincter pharyngoplasty. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary care center. METHODS: Patients were included who were aged ≥18 years old and underwent upper airway stimulation, transoral robotic surgery, or expansion sphincter pharyngoplasty between January 2011 and May 2020. RESULTS: 345 patients were identified: 58% (n = 201) underwent upper airway stimulation, 10% (n = 35) underwent transoral robotic surgery, and 32% (n = 109) patients underwent expansion sphincter pharyngoplasty. There were 22 emergency department presentations and 19 readmissions, most of which were experienced by patients receiving transoral robotic surgery (six emergencies, seven readmissions) and expansion sphincter pharyngoplasty (12 emergencies, 11 readmissions). Patients with upper airway stimulation had four emergencies and one readmission. Only 2% of the upper airway stimulation cohort had a complication, whereas this was 20% and 12% for the transoral robotic surgery and expansion sphincter pharyngoplasty cohorts, respectively. Patients experienced the highest surgical success rate with upper airway stimulation (69%), whereas patients who received transoral robotic surgery and expansion sphincter pharyngoplasty had success rates of 50% and 51%, respectively. CONCLUSION: Treating obstructive sleep apnea with upper airway stimulation led to lower rates of complications, emergency department presentations, and readmissions in this series. In those for whom upper airway stimulation is appropriate, it may be more effective in successfully treating obstructive sleep apnea than transoral robotic surgery and expansion sphincter pharyngoplasty.

Hypoglossal nerve stimulation impact on a patient with obstructive sleep apnea and heart failure.

A 75-year-old man with body mass index of 30.5 kg/m² and severe obstructive sleep apnea (OSA) with an apnea-hypopnea index (AHI) of 72 events/h was referred for upper airway stimulation (UAS) therapy. Past medical history was significant for cardiovascular disease including congestive heart failure due to ischemic cardiomyopathy with impaired left ventricular function and ejection fraction of 35%. Following evaluation of clinical and polysomnographic data, he was an appropriate candidate for UAS and underwent uncomplicated implantation. Three months postoperatively, polysomnography showed a titrated AHI of 0 events/h. Follow-up cardiac evaluation revealed ejection fraction increase to 47% since implantation. No interval change in medical management or body mass index had occurred. Given the high prevalence of OSA in patients with cardiovascular disease, UAS may become an important adjunct in the comprehensive multidisciplinary treatment of heart failure in patients with OSA. Further clinical studies are required to investigate the impact of UAS on treatment and prognosis of heart disease.

Drug-Induced Sleep Endoscopy and Hypoglossal Nerve Stimulation Outcomes: A Multicenter Cohort Study.

OBJECTIVES/HYPOTHESIS: To determine the association between findings of blinded reviews of preoperative drug-induced sleep endoscopy (DISE) and outcomes of hypoglossal nerve stimulation (HNS) for obstructive sleep apnea (OSA). STUDY DESIGN: Cohort study. METHODS: A retrospective, multicenter cohort study of 343 adults who underwent treatment of OSA with HNS from 10 academic medical centers was performed. Preoperative DISE videos were scored by four blinded reviewers using the VOTE Classification and evaluation of a possible primary structure contributing to airway obstruction. Consensus DISE findings were examined for an association with surgical outcomes based on therapy titration polysomnogram (tPSG). Treatment response was defined by a decrease of ≥50% in the apnea-hypopnea index (AHI) to <15 events/hour. RESULTS: Study participants (76% male, 60.4 ± 11.0 years old) had a body mass index of 29.2 ± 3.6 kg/m2 . AHI decreased (35.6 ± 15.2 to 11.0 ± 14.1 events/hour; P < .001) on the tPSG, with a 72.6% response rate. Complete palate obstruction (vs. none) was associated with the greatest difference in AHI improvement (-26.8 ± 14.9 vs. -19.2 ± 12.8, P = .02). Complete (vs. partial/none) tongue-related obstruction was associated with increased odds of treatment response (78% vs. 68%, P = .043). Complete (vs. partial/none) oropharyngeal lateral wall-related obstruction was associated with lower odds of surgical response (58% vs. 74%, P = .042). CONCLUSIONS: The DISE finding of primary tongue contribution to airway obstruction was associated with better outcomes, whereas the opposite was true for the oropharyngeal lateral walls. This study suggests that the role for DISE in counseling candidates for HNS extends beyond solely for excluding complete concentric collapse related to the velum. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:1676-1682, 2021.

Comparison of Traditional Upper Airway Surgery and Upper Airway Stimulation for Obstructive Sleep Apnea.

OBJECTIVE: To compare patients with moderate-severe obstructive sleep apnea (OSA) undergoing traditional single and multilevel sleep surgery to those undergoing upper airway stimulation (UAS). STUDY DESIGN: Case control study comparing retrospective cohort of patients undergoing traditional sleep surgery to patients undergoing UAS enrolled in the ADHERE registry. SETTING: 8 multinational academic medical centers. SUBJECTS AND METHODS: 233 patients undergoing prior single or multilevel traditional sleep surgery and meeting study inclusion criteria were compared to 465 patients from the ADHERE registry who underwent UAS. We compared preoperative and postoperative demographic, quality of life, and polysomnographic data. We also evaluated treatment response rates. RESULTS: The pre and postoperative apnea hypopnea index (AHI) was 33.5 and 15 in the traditional sleep surgery group and 32 and 10 in the UAS group. The postoperative AHI in the UAS group was significantly lower. The pre and postoperative Epworth sleepiness scores (ESS) were 12 and 6 in both the traditional sleep surgery and UAS groups. Subgroup analysis evaluated those patients undergoing single level palate and multilevel palate and tongue base traditional sleep surgeries. The UAS group had a significantly lower postoperive AHI than both traditional sleep surgery subgroups. The UAS group had a higher percentage of patients reaching surgical success, defined as a postoperative AHI <20 with a 50% reduction from preoperative severity. CONCLUSION: UAS offers significantly better control of AHI severity than traditional sleep surgery. Quality life improvements were similar between groups.

Evaluation of Surgical Learning Curve Effect on Obstructive Sleep Apnea Outcomes in Upper Airway Stimulation.

OBJECTIVE: An increasing number of facilities offer Upper Airway Stimulation (UAS) with varying levels of experience. The goal was to quantify whether a surgical learning curve exists in operative or sleep outcomes in UAS. METHODS: International multi-center retrospective review of the ADHERE registry, a prospective international multi-center study collecting UAS outcomes. ADHERE registry centers with at least 20 implants and outcomes data through at least 6-month follow-up were reviewed. Cases were divided into two groups based on implant order (the first 10 or second 10 consecutive implants at a given site). Group differences were assessed using Mann-Whitney U-tests, Chi-squared tests, or Fisher's Exact tests, as appropriate. A Mann-Kendall trend test was used to detect if there was a monotonic trend in operative time. Sleep outcome equivalence between experience groups was assessed using the two one-sided tests approach. RESULTS: Thirteen facilities met inclusion criteria, contributing 260 patients. Complication rates did not significantly differ between groups (P = .808). Operative time exhibited a significant downward trend (P < .001), with the median operative time dropping from 150 minutes for the first 10 implants to 134 minutes for the subsequent 10 implants. The decrease in AHI from baseline to 12-month follow-up was equivalent between the first and second ten (22.8 vs 21.2 events/hour, respectively, P < .001). Similarly, the first and second ten groups had equivalent ESS decreases at 6 months (2.0 vs 2.0, respectively, P < .001). ESS outcomes remained equivalent for those with data through 12-months. CONCLUSIONS: Across the centers' first 20 implants, an approximately 11% reduction operative time was identified, however, no learning curve effect was seen for 6-month or 12-month AHI or ESS over the first twenty implants. Ongoing monitoring through the ADHERE registry will help measure the impact of evolving provider and patient specific characteristics as the number of implant centers increases.

Elevated Central and Mixed Apnea Index after Upper Airway Stimulation.

OBJECTIVE: Upper airway stimulation (UAS) is used to treat patients with moderate to severe obstructive sleep apnea (OSA). The aim of this study is to report the incidence and potential predictors of elevated central and mixed apnea index (CMAI) after UAS. STUDY DESIGN: Retrospective chart review of patients undergoing UAS. SETTING: Tertiary care center. SUBJECTS AND METHODS: Included patients underwent UAS for OSA at our institution between 2014 and 2018. Data collected included demographic information, implantation records, and pre- and postoperative polysomnography (PSG) results. CMAI ≥5 was considered elevated. Post hoc univariate analysis was performed to evaluate factors associated with elevated CMAI. RESULTS: In total, 141 patients underwent UAS at our institution. This included 94 men and 47 women with a mean age of 61.2 ± 11.0 years and a mean body mass index of 29.1 ± 3.9 kg/m2. Five patients had an elevated CMAI after surgery during UAS titration. Demographics, comorbid conditions, and device settings were not associated with an elevated postoperative CMAI (P > .05). CONCLUSION: The occurrence of an elevated CMAI after surgery may represent treatment-emergent events. Demographics, comorbid conditions, and UAS device settings were not associated with central and mixed apneic events. LEVEL OF EVIDENCE: 4.

Effect of Gender, Age, and Profound Disease on Upper Airway Stimulation Outcomes.

OBJECTIVE: To evaluate treatment outcomes of upper airway stimulation (UAS) in obstructive sleep apnea (OSA) patients based on patient age, gender, and preoperative disease severity. METHODS: Retrospective chart review of patients undergoing UAS from 2014 to 2018 at a tertiary care center. Data collected included demographic information, implantation records, and pre- and postoperative polysomnography (PSG) results. Profound OSA was defined as AHI >65 and age ≥65 was considered advanced age. The primary outcome measured was initial treatment response, defined as a post-operative AHI <20 with a >50% reduction from baseline. RESULTS: 145 patients underwent UAS at our institution including 98 males and 47 females with a mean age of 61.7 ± 11.5 years, mean BMI of 29.1 ± 3.9 kg/m2, and mean preoperative AHI of 34.1 ± 18.2 events/hour. After surgery, patients had a significantly lower mean AHI of 8.6 ± 15.0 events/hour (<0.001). Older patients had a lower initial treatment response rate (78%) when compared to their younger counterparts (94%) (P = 0.005). Male gender and profound disease status did not significantly impact treatment response rates; young age was the only variable found to predict early treatment response on multivariate analysis (P = 0.003). CONCLUSION: Although the overall OSA population showed significant postoperative AHI reduction with UAS, patients age ≥65 years were less likely to have an initial response to treatment, when compared to their younger counterparts. A larger proportion of elderly patients and patients with profound OSA had residual moderate disease (AHI > 15) after UAS. LEVEL OF EVIDENCE: 4.

Does Insurance Status Impact Delivery of Care with Upper Airway Stimulation for OSA?

OBJECTIVE: To understand differences in patient demographics, insurance-related treatment delays, and average waiting times for Medicare and private insurance patients undergoing upper airway stimulation (UAS) for treatment of obstructive sleep apnea (OSA). METHODS: Retrospective chart review of all Medicare and private insurance patients undergoing upper airway stimulation (UAS) from 2015 to 2018 at a single academic center. Primary outcomes were insurance-related procedure cancellation rate and time from drug induced sleep endoscopy (DISE) and UAS treatment recommendation to UAS surgery in Medicare versus private insurance patients. RESULTS: In our cohort 207 underwent DISE and were recommended treatment with UAS. Forty-four patients with Medicare and 30 patients with private insurance underwent UAS procedure. Patients with Medicare undergoing UAS were older (67.4 ± 11.1 years) than patients with private insurance (54.9 ± 8.1 years). Medicare patients had a shorter mean wait time of 121.9 ± 75.8 days (range, 15-331 days) from the time of UAS treatment recommendation to UAS surgery when compared to patients with private insurance (201.3 ± 102.2 days; range, 33-477 days). Three patients with Medicare (6.4%) and 8 patients with private insurance (21.1%) were ultimately denied UAS. CONCLUSION: Medicare patients undergoing UAS have shorter waiting periods, fewer insurance-related treatment delays and may experience fewer procedure cancellations when compared to patients with private insurance. The investigational status of UAS by private insurance companies delays care for patients with OSA. LEVEL OF EVIDENCE: 4.

Inclusion of the first cervical nerve does not influence outcomes in upper airway stimulation for treatment of obstructive sleep apnea.

OBJECTIVES/HYPOTHESIS: Upper airway stimulation (UAS) has demonstrated efficacy in the management of obstructive sleep apnea (OSA). Branches of the hypoglossal nerve that selectively activate tongue protrusor and stiffener muscles are included within the stimulation cuff electrode. The first cervical nerve (C1) is often also included to stimulate additional muscles contributing to tongue protrusion and stabilization. The purpose of this study was to determine whether inclusion of the C1 translates into treatment efficacy, decreased voltage requirement, and improved outcomes in patients utilizing UAS. STUDY DESIGN: Single-center, retrospective cohort study. METHODS: One hundred fourteen patients who received a UAS implant at our institution and underwent posttreatment polysomnography were evaluated. Stimulation cuff electrodes in 87 patients included the C1; those in the remaining 27 patients did not include the C1. Demographic data, voltage data, and pre- and posttreatment apnea-hypopnea index (AHI), O2 nadir, and Epworth Sleepiness Scale (ESS) data were collected for all patients. RESULTS: There was no significant difference in stimulation voltage, or posttreatment AHI, O2 nadir, and ESS between the two cohorts. Treatment success, as measured by posttreatment AHI < 20 with a 50% reduction, was similar regardless of C1 inclusion. The same was seen for the percent of patients with AHI < 15 and AHI < 5 after treatment. The distributions of age and body mass index, as well as pre-treatment AHI, O2 nadir, and ESS were also not significantly different between treatment groups. CONCLUSIONS: The current study has demonstrated that inclusion of the C1 in the stimulation cuff electrode of the upper airway stimulator may not provide any additional benefit in therapy for OSA. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E382-E385, 2020.

Results of the ADHERE upper airway stimulation registry and predictors of therapy efficacy.

OBJECTIVE/HYPOTHESIS: The ADHERE Registry is a multicenter prospective observational study following outcomes of upper airway stimulation (UAS) therapy in patients who have failed continuous positive airway pressure therapy for obstructive sleep apnea (OSA). The aim of this registry and purpose of this article were to examine the outcomes of patients receiving UAS for treatment of OSA. STUDY DESIGN: Cohort Study. METHODS: Demographic and sleep study data collection occurred at baseline, implantation visit, post-titration (6 months), and final visit (12 months). Patient and physician reported outcomes were also collected. Post hoc univariate and multivariate analysis was used to identify predictors of therapy response, defined as ≥50% decrease in Apnea-Hypopnea Index (AHI) and AHI ≤20 at the 12-month visit. RESULTS: The registry has enrolled 1,017 patients from October 2016 through February 2019. Thus far, 640 patients have completed their 6-month follow-up and 382 have completed the 12-month follow-up. After 12 months, median AHI was reduced from 32.8 (interquartile range [IQR], 23.6-45.0) to 9.5 (IQR, 4.0-18.5); mean, 35.8 ± 15.4 to 14.2 ± 15.0, P < .0001. Epworth Sleepiness Scale was similarly improved from 11.0 (IQR, 7-16) to 7.0 (IQR, 4-11); mean, 11.4 ± 5.6 to 7.2 ± 4.8, P < .0001. Therapy usage was 5.6 ± 2.1 hours per night after 12 months. In a multivariate model, only female sex and lower baseline body mass index remained as significant predictors of therapy response. CONCLUSIONS: Across a multi-institutional study, UAS therapy continues to show significant improvement in subjective and objective OSA outcomes. This analysis shows that the therapy effect is durable and adherence is high. LEVEL OF EVIDENCE: 2 Laryngoscope, 130:1333-1338, 2020.

The Impact of Upper Airway Stimulation on Swallowing Function.

OBJECTIVE: To evaluate the impact of upper airway stimulation therapy (UAS) on swallowing function in patients with obstructive sleep apnea. STUDY DESIGN: Prospective cohort study. SETTING: Academic medical center. PARTICIPANTS AND OUTCOME MEASURES: We recorded demographic, preoperative polysomnogram (PSG), operative, and postoperative PSG data. We assessed the patients swallowing function using the Eating Assessment Tool (EAT-10) dysphagia questionnaire. This was administered both pre- and postoperatively. The postoperative EAT-10 survey was administered at least 3 months after UAS implantation. RESULTS: During the study period, 27 patients underwent UAS implantation, completed the pre- and postoperative EAT-10 questionnaire, met inclusion/exclusion criteria, and were included in the study. The cohort consisted of 16 men and 11 women with a mean age of 63.63 years. The mean preoperative BMI, Epworth Sleepiness Scale (ESS), and Apnea Hypopnea Index (AHI) were 29.37, 10.33, and 34.90, respectively. The mean postoperative ESS and AHI were 5.25 and 7.59, respectively. These were both significantly lower than the preoperative values (P = .026 and P < .001). The mean pre- and postoperative EAT-10 scores were 0.37 and 0.22, respectively (P = .461). CONCLUSION: Our data suggest that UAS likely does not lead to postoperative dysphagia.

Comparing Upper Airway Stimulation to Transoral Robotic Base of Tongue Resection for Treatment of Obstructive Sleep Apnea.

OBJECTIVES: Transoral robotic surgery (TORS) and upper airway stimulation (UAS) are modalities for treating tongue base obstruction contributing to obstructive sleep apnea (OSA). We aim to compare patients with OSA undergoing TORS to those undergoing UAS. METHODS: We retrospectively reviewed patients treated with TORS and UAS using the senior authors' surgical database. We evaluated demographic, preoperative polysomnography (PSG), postoperative PSG, complication, hospital length of stay, and hospital readmission data to compare the two cohorts. RESULTS: Seventy-six patients underwent UAS. This included 50 men and 26 women. The mean age and body mass index were 61.92 and 29.38. The mean pre- versus postoperative apnea hypopnea index (AHI) and O2 nadir were 36.64 versus 7.20 and 80.27% versus 88.77%, respectfully. The rate of surgical success and postoperative AHI less than 15 and 5 were 86.84%, 89.47%, and 59.21. All patients underwent ambulatory surgery, and no one was readmitted. Twenty-four patients underwent TORS. This included 20 men and four women with a mean age and body mass index BMI of 46.42 and 29.63. The mean pre- versus postoperative AHI and O2 nadir were 35.70 versus 20.05 and 80.50% versus 84.10%, respectfully. The rate of surgical success and postoperative AHI less than 15 and 5 were 54.17%, 50.00%, and 20.83%. The mean length of stay was 1.33 days, and four patients were readmitted. We found significant differences in age, postoperative AHI and O2 nadir, surgical success and postoperative AHI less than 15 and 5, length of stay, and rate of readmission. CONCLUSIONS: UAS is successful in treating OSA showing improved outcomes, length of stay, and readmission compared to TORS. LEVEL OF EVIDENCE: 3 Laryngoscope, 129:1010-1013, 2019.

Dysfunctional hypoglossal nerve stimulator after electrical cardioversion: A case series.

OBJECTIVES/HYPOTHESIS: Upper airway stimulation has demonstrated marked improvements in apnea-hypopnea index, oxygen desaturation index, and quality-of-life measures in patients with moderate to severe obstructive sleep apnea (OSA) who cannot tolerate continuous positive airway pressure. Cardiac arrhythmias are common in patients with OSA and can require electrical cardioversion. We describe the first four reported cases of hypoglossal nerve stimulator (HGNS) dysfunction after electrical cardioversion and illustrate our operative approach to device troubleshooting and repair. STUDY DESIGN: Retrospective case series. METHODS: A retrospective review of 201 HGNS implantations performed at two academic institutions revealed four cases of HGNS device dysfunction after electrical cardioversion requiring surgical revision. Preoperative and postoperative device performance metrics and electrical cardioversion specifications were retrospectively assessed and compiled for this case series. The senior authors (R.J.S., M.S.B.) detail operative planning and approach for HGNS implantable pulse generator (IPG) replacement. RESULTS: At least two patients with HGNS device dysfunction had received cardioversion via anterolateral electrode pad placement. Three patients had received multiple shocks. All four patients experienced a change in device functionality or complete cessation of functionality after electrocardioversion. Operatively, each patient required replacement of the IPG, with subsequent intraoperative interrogation revealing proper device functionality. CONCLUSION: Counseling for patients with HGNS undergoing external electrical cardioversion should include possible device damage and need for operative replacement. Anteroposterior electrode pad placement should be considered for patients with HGNS who require electrocardioversion. Operative replacement of an HGNS system damaged by electrocardioversion begins with IPG replacement and intraoperative device interrogation. LEVEL OF EVIDENCE: 4 Laryngoscope, 129:1949-1953, 2019.

Upper Airway Stimulation in Patients With Obstructive Sleep Apnea and an Elevated Body Mass Index: A Multi-institutional Review.

OBJECTIVES/HYPOTHESIS: An elevated body mass index (BMI) influences the severity of disease and treatment options utilized for obstructive sleep apnea (OSA). With this study, we aim to evaluate a cohort of patients undergoing upper airway stimulation (UAS) for treatment of OSA and assess the impact of BMI on surgical and quality of life outcomes. METHODS: We designed a case-control, retrospective review, of all patients undergoing UAS at two academic institutions between 2014 and 2017. We compare those with an elevated BMI to those without. We included patients with moderate-severe OSA, who were unable to tolerate therapy with continuous positive airway pressure (CPAP), were treated with UAS, and had a postoperative sleep study performed. We evaluated postoperative sleep study data including apnea-hypopnea index (AHI), O2 desaturation nadir, rate of cure, and rate of success in those with an elevated BMI to those without an elevated BMI. Success was defined as a drop in the postoperative AHI by 50% compared to the preoperative value and to less than 20. We also assessed daytime sleepiness using the Epworth Sleepiness Scale. RESULTS: When defining an elevated BMI as greater than 32, we found no difference between elevated and nonelevated BMI cohorts in postoperative AHI, O2 desaturation nadir, daytime sleepiness, rate of surgical success, or rate of cure. CONCLUSIONS: Patients with obstructive sleep apnea, unable to tolerate CPAP, and with an elevated BMI can be successfully treated with upper airway stimulation therapy. LEVEL OF EVIDENCE: 3. Laryngoscope, 128:2425-2428, 2018.