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Obstructive sleep apnea (OSA) is a common medical condition with an increasing prevalence. Repeated episodes of hypopnea or apnea can cause hypoxia, hypercapnia, and sleep fragmentation. As a result, patients with OSA can suffer from various symptoms, including snoring or gasping for air at night, excessive sleepiness, headache, irritability, difficulty concentrating, and decreased libido. Untreated OSA is associated with numerous adverse health outcomes, including increased motor vehicle accidents, hypertension, type II diabetes, strokes, atrial fibrillation, coronary artery disease, heart failure, and increased overall mortality. Hypoglossal nerve stimulation is a therapeutic option for treating OSA in patients with moderate-to-severe OSA who are resistant to or intolerant of continuous positive pressure ventilation therapy. The hypoglossal nerve stimulator detects inspiratory effort during sleep and activates upper airway musculature to prevent airway collapse. This activity reviews the anatomy and physiology, indications, contraindications, complications, and benefits of therapeutic hypoglossal nerve stimulation. Finally, this activity will highlight the role of the interprofessional team in evaluating and managing patients with OSA who receive a hypoglossal nerve stimulator. Objectives: Correlate the anatomy of the upper airway and the physiology of breathing to understand the mechanisms involved in maintaining upper airway patency and the application of hypoglossal nerve stimulation. Identify patients with obstructive sleep apnea who may benefit from hypoglossal nerve stimulation based on their clinical indicators and the absence of absolute contraindications to the procedure. Apply the results of clinical trials evaluating the efficacy of hypoglossal nerve stimulation when counseling patients considering the procedure. Utilize effective interprofessional and interdisciplinary team processes in the outpatient clinic and hospital settings to improve outcomes for patients with obstructive sleep apnea who have undergone hypoglossal nerve stimulator placement. Access free multiple choice questions on this topic.

Obstructive sleep apnea (OSA) is a common medical condition with an increasing prevalence, occurring in 9% to 25% of men and 9% to 15% of women.[1][2] OSA is defined as upper airway collapse resulting in a decrease (hypopnea) or airflow loss (apnea) for at least 10 seconds.[3] Repeated episodes of hypopnea or apnea can cause hypoxia, hypercapnia, and sleep fragmentation.[4] As a result, patients can suffer from various symptoms, including snoring or gasping for air at night, excessive sleepiness, headache, irritability, difficulty concentrating, and decreased libido.[5] Traditionally, the diagnosis of OSA relied on in-lab polysomnography. However, home sleep apnea testing is now an acceptable alternative diagnostic tool. The results from either of these tests can determine the severity of OSA using the apnea-hypopnea index (AHI) defined by the American Academy of Sleep Medicine. The severity levels are categorized as follows: Mild OSA (AHI 5-15), Moderate OSA (AHI 15-30), and Severe OSA (AHI >30).[5] Untreated OSA is associated with numerous adverse health outcomes, including increased motor vehicle accidents, hypertension, type 2 diabetes, strokes, atrial fibrillation, coronary artery disease, heart failure, and increased overall mortality.[6][7][8] The gold standard for treating OSA is continuous positive airway pressure (CPAP) administered via various face or nasal masks. While this treatment improves overall sleep quality and has proven effective in reducing blood pressure and the AHI, compliance is challenging for many patients, with 29% to 83% reporting <4 hours of CPAP use per night.[9][10] Compliance with treatment is especially challenging over time; noncompliance rates with long-term use range from 11% to 45%.[11][12] Hypoglossal nerve stimulation (HGNS) is a surgical option for treating OSA. During this procedure, a stimulator is connected to the hypoglossal nerve, which controls the genioglossus muscle. When the nerve is stimulated, it triggers the contraction of the muscle, effectively preventing the collapse of the upper airway.[13] Studies have shown that HGNS significantly improves the quality of life, AHI, and oxygen desaturation index (ODI).[14]

In the Stimulation Therapy for Apnea Reduction (STAR) multicenter prospective trial, 2% of patients had a severe adverse event following device placement that resulted in the need for repositioning or fixations of the stimulator.[14] Other major surgical complications, such as hematoma formation and pneumothorax, have occurred but are rare.[19] The STAR trial also reported several nonserious adverse events related to the device or the placement procedure. Procedure-related events included incisional postoperative discomfort in 26% of patients and nonincisional postoperative discomfort in 25%. Other reported events included temporary tongue weakness (18%), intubation effects (12%), headache (6%), other symptoms (11%), and mild infection (1%).[14] These complications were demonstrated to be transient in the five-year follow-up study. This follow-up study reported that only 1 or 2 incisional discomfort events occurred per year after the first year, while only 1 nonincisional discomfort event was reported in the third year. None of the other postoperative complications were noted after the first year.[22] Device-related complications reported in the STAR trial included discomfort from electrical stimulation (40%), tongue abrasion (21%), dry mouth (10%), mechanical pain due to device presence (6%), temporary internal device functionality issues (10%), temporary external device use or function issues (6%), other symptoms (15%), and mild or moderate infection (1%).[14] These complications also became less common after the first year, particularly when looking at the most common complication, namely discomfort from electrical stimulation. In the fifth year following device placement, only 5 events of discomfort due to electrical stimulation were reported, compared to 81 in the first 12 months.[22] The prospective Adherence and Outcome of Upper Airway Stimulation for OSA International Registry (ADHERE Registry) indicates that the most common complication associated with HGNS was discomfort due to stimulation, which decreased from 12% at 6 months to 8% at 12 months.[23] The reduced incidence of discomfort due to stimulation during later postoperative visits is likely attributable to adjustments in the level of stimulation provided.[22]

The primary management of OSA has traditionally been CPAP. Unfortunately, many patients do not tolerate CPAP and often go untreated. In these patients, HGNS represents a safe and viable alternative.[23] (level III). However, the stimulator placement involves a surgical procedure, multiple follow-up visits, and titration polysomnography. Therefore, the decision to utilize HGNS as a treatment for OSA should be based on robust discussion between the patient and an interdisciplinary healthcare team of primary care, sleep medicine, and otolaryngology providers.