The Hypoglossal Nerve Stimulation as a Novel Therapy for Treating Obstructive Sleep Apnea-A Literature Review

Cost and Efficiency of Drug-Induced Sleep Endoscopy: Endoscopy Suite Versus Outpatient Surgery Center

OBJECTIVE

Drug-induced sleep endoscopy (DISE) is used to identify airway obstruction patterns in patients with obstructive sleep apnea (OSA). This procedure is typically performed in either the traditional operating room (OR) or an outpatient surgery center (SC). There is limited data regarding the cost and efficiency of DISE in the endoscopy suite (ES). This study compares the cost, efficiency, and safety of DISE performed in the ES compared to the SC.

METHODS

This retrospective review included patients who underwent DISE between July 2023 and April 2024 at a single tertiary care center. Consecutive patients with CPAP-intolerant OSA undergoing DISE in the ES or SC were included. Patient demographics, sleep studies, procedure-related costs, procedure duration characteristics, and anesthesia documentation were analyzed.

RESULTS

Eighty-four patients (36 ES, 48 SC) were included. Patient sex, age, BMI, and preoperative AHI/REI were similar in both cohorts (p > 0.05). DISE in the ES significantly reduced total facility time (48 min, p < 0.0001), time in procedure room (6.6 min, p < 0.0001), DISE procedure time (1.7 min, p = 0.0034), total recovery time (30.4 min, p < 0.0001), and procedure room turnover time (7.1 min, p = 0.0012). Costs for ES procedures were 39.35% lower, specifically in costs associated with anesthesia, operating room, and recovery room (all comparisons, p < 0.001). No complications occurred in either group.

CONCLUSIONS

Performing DISE in the ES increases efficiency and reduces costs compared to the outpatient SC while maintaining safety for patients with CPAP-intolerant OSA.

LEVEL OF EVIDENCE: 3

Impact of Nasal Pathology on Efficacy of Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea

OBJECTIVES

Hypoglossal nerve stimulation (HNS) has emerged as a treatment for obstructive sleep apnea (OSA). While current literature suggests comorbid nasal pathology can decrease quality of life (QoL) in OSA populations, its impact on HNS efficacy has been less explored. This study assesses whether the presence of nasal pathology changes HNS efficacy in improving sleep outcomes in OSA patients.

METHODS

A retrospective analysis evaluated 90 patients who underwent HNS implantation. Treatment efficacy and QoL were assessed preoperatively and postoperatively with apnea-hypopnea index (AHI), Epworth sleepiness scale (ESS), and functional outcomes of sleep questionnaire (FOSQ-10). Nasal exam and nasopharyngoscopy findings derived four groups: normal nasal findings (n = 44), positive anterior rhinoscopy findings (n = 32), positive nasopharyngoscopy findings (n = 36), and any positive nasal finding (n = 46). Septal deviation, septal perforation, polyps, masses, vestibular stenosis, and turbinate hypertrophy were considered positive findings. Outcomes within and across groups were analyzed using t-tests, Mann-Whitney U-tests, and Wilcoxon signed-rank tests.

RESULTS

Both AHI and ESS scores significantly improved across all groups (p < 0.05) following HNS. FOSQ-10 in patients with positive anterior rhinoscopy findings did not significantly improve. Average FOSQ-10 improvement was significantly greater in the control group compared to the positive anterior rhinoscopy findings (p < 0.05). All groups met Sher15 and Sher20 criteria at similar rates.

CONCLUSIONS

Comorbid nasal pathology does not diminish the effectiveness of HNS in treating OSA, with all groups showing significant improvement in AHI and ESS scores. However, impacts on broader QoL, measured by FOSQ-10, warrant further investigation.

LEVEL OF EVIDENCE: 3

Beyond the mouth: An overview of obstructive sleep apnea in adults for dentists

Obstructive sleep apnea (OSA) is a common and complex medical sleep condition in adults that is associated with chronic medical and mental health conditions. Left undiagnosed and untreated it can decrease quality of life and increase morbidity and mortality. Dentists are at the forefront for screening OSA in their role to maintain the health of the oral cavity. Clinical experience in the management of OSA in dentists is limited. The aim of this article is to provide dentists with foundational knowledge about OSA to empower them to play an active role in the care management of screening and treating OSA.

Effects of Hypoglossal Nerve Stimulation on Upper Airway Structure and Function Using Moving Wall Computational Fluid Dynamics Simulations: A Pilot Study

Hypoglossal nerve stimulation (HGNS) is an innovative alternative treatment option for obstructive sleep apnoea (OSA) in patients unable to tolerate continuous positive airway pressure. However, the success rate of HGNS is variable, but the reasons underlying variation in treatment efficacy are not well understood. In this pilot study of three male subjects, we propose an innovative, non-invasive method to quantify the structural and functional changes to the upper airway that occur with HGNS. We used four-dimensional computed tomography (4DCT) and computational fluid dynamics (CFD) simulations of respiratory airflow to quantify how HGNS changes: (1) airway cross-sectional area (CSA), (2) work done by muscles and air pressure in dilating and collapsing the airway and (3) airway resistance. Subjects underwent 4DCT under natural stage non-REM 2 (N2) sleep with and without HGNS. Each patient had concurrent electroencephalograms and airflow measurements. CFD simulations were performed based on anatomy and airway motion from 4DCT images and airflow data. HGNS was associated with an increase in neuromuscular work done in dilating the airway (up to 490%); airway CSA increased by up to 300%. Most motion with HGNS occurred in the oropharynx; changes in the nasopharynx and hypopharynx varied between subjects. Minute ventilation increased in all subjects (15%-36%). Airway resistance decreased across the three subjects (73%-97%). Quantifying the parameters measured in this study may help explain variable responses to HGNS as a treatment for OSA. These procedures may, in future, help predict non-responders to HGNS, isolate reasons for poor responses, or inform device titration.

Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea and Comorbid Neuromuscular Disorders

Hypoglossal nerve stimulation (HGNS) is an effective surgical treatment for many patients with moderate-to-severe obstructive sleep apnea (OSA) who are unable to tolerate continuous positive airway pressure. Patients with neuromuscular disorders (NMD) are particularly vulnerable to more complex sleep-related breathing disorders due to respiratory muscle weakness and the associated risk of hypoventilation. In this study, we present five patients with myasthenia gravis (n = 2), muscular dystrophy, Charcot-Marie-Tooth, and advanced multiple sclerosis who underwent HGNS therapy for OSA. At time of surgery, the mean patient age was 54 ± 18.7 years and mean BMI was 24.6 ± 4.6 kg/m2. Mean device adherence was 8 ± 1.1 h/night at three months and 7.2 ± 1.7 h/night at 12 months. Mean apnea-hypopnea index (AHI) improved significantly from preoperative baseline (34.9 to 8.5, p = 0.03) and 5/6 patients had a postoperative AHI <5. Epworth Sleepiness Scale scores significantly improved postoperatively (13.1-8.5, p = 0.03). Oxygen nadir trended upward (75.5-85.3, p = 0.84). Our limited findings demonstrate that HGNS was a safe and effective treatment for five patients with OSA and comorbid NMD. Prospective studies and larger sample sizes are warranted to support our findings and confirm whether HGNS is a potential therapeutic option for this unique patient population. Laryngoscope, 2025.

Polysomnographic features of hypoglossal nerve stimulation efficacy: Looking deeper than the apnea-hypopnea index

Objectives

Hypoglossal nerve stimulation (HGNS) is a promising surgical option for patients with obstructive sleep apnea (OSA) who are intolerant of continuous positive airway pressure therapy (CPAP). Efficacy studies for HGNS stimulation largely focus on the apnea-hypopnea index and/or oxygen desaturation index. This study's objective was to show the physiological effects of HGNS stimulation on upper airway patency, airflow, and treatment effect during polysomnography (PSG) testing.

Methods

PSG tracings from patients implanted with an Inspire© HGNS device were reviewed for this study. Nasal pressure was utilized as a surrogate for respiratory flow and chin electromyography was used to detect HGNS stimulation, allowing for breath-to-breath analysis. Per our sleep laboratory protocol, the HGNS device was turned on and off at different periods of the night. Respiratory tracings during these periods were visually analyzed.

Results

Analysis of on-off periods of HGNS therapy during PSG allows for a concise assessment of HGNS efficacy. The presence of inspiratory flow limitation and subsequent apneas or hypopneas upon turning off HGNS stimulation with restoration of stable, unobstructed breathing upon resuming HGNS stimulation indicates a positive treatment effect related to HGNS therapy. Despite the respiratory-sensing capacity of the Inspire HGNS device, desynchrony of stimulation and inspiration is observed. Desynchrony yields partially captured inspiratory cycles, allowing for assessment of HGNS effect on an individual breath.

Conclusion

Night-to-night and intranight variability in OSA severity makes assessing the effect of HGNS complex. Strategic testing protocols during postoperative PSG can provide critical insight into the effect of this therapy on upper airway obstruction during sleep. On-off periods of stimulation provide a concise assessment of the effect of HGNS on preventing upper airway collapse and help to account for night-to-night and intranight variability. Respiratory desynchrony associated with HGNS therapy exists. Observing partially-stimulated inspiratory cycles allow for assessment of HGNS's effect on a single breath.

Level of Evidence

4.

Exploring the pharmacological mechanisms for alleviating OSA: Adenosine A2A receptor downregulation of the PI3K/Akt/HIF‑1 pathway (Review)

Obstructive sleep apnea (OSA) is the most common type of sleep apnea, which leads to episodes of intermittent hypoxia due to obstruction of the upper airway. A key feature of OSA is the upregulation and stabilization of hypoxia-inducible factor 1 (HIF-1), a crucial metabolic regulator that facilitates rapid adaptation to changes in oxygen availability. Adenosine A2A receptor (A2AR), a major adenosine receptor, regulates HIF-1 under hypoxic conditions, exerting anti-inflammatory properties and affecting lipid metabolism. The present study explored the roles of A2AR in OSA regulation, specifically focusing on its effects via the PI3K/Akt/HIF-1 pathway. The findings enhance our understanding the pharmacological potential of A2AR in OSA management and suggest future research directions in exploring its clinical applications.

CPAP Therapy for OSA and Its Impact on Various Cardiovascular Disorders

Obstructive sleep apnea (OSA), a highly prevalent and serious disorder with significant complications, causes considerable daytime and nighttime symptoms as well as long-term consequences and is yet an underdiagnosed and inadequately treated condition. Patients with OSA undergo frequent awakenings during the sleep cycle and find it impossible to get restorative sleep. Individuals are extremely fatigued, sleepy, and irritable throughout the day. Reduced exercise performance and physical activity contribute to a decrease in energy metabolism and weight gain. Those in this population may experience decreased motivation, which could result in depressive symptoms. The abrupt drops in oxygen levels during the sleep cycle result in profound spikes in blood pressure and strain the cardiovascular system. Given its close tie with major cardiovascular risk factors, OSA is linked with various cardiovascular diseases, including coronary artery disease, cardiac arrhythmia, poorly controlled blood pressure, heart failure, and stroke. Continuous positive airway pressure is an effective and tried-trusted approach for symptom relief and improving quality of life. Despite its benefits, patients struggle with compliance and often go untreated because of physical discomfort and perceived inconvenience of using these machines. One other explanation for this could be the lack of awareness, comprehensive data, and extensive research on its effects on long-term cardiovascular and metabolic complications caused by OSA. The current standard treatment for OSA, using adequate positive airway pressure, greatly reduces cardiovascular morbidity. Nevertheless, patients with cardiovascular disorders continue to be highly susceptible to OSA and its detrimental clinical consequences, even with effective therapy available. In summary, continuous positive airway pressure has an indirect potential to affect cardiovascular outcomes, but further studies should be done to address issues with patient compliance and adherence.

Exploring the therapeutic potential of GLP-1 receptor agonists in the management of obstructive sleep apnea: a comprehensive review

Obstructive Sleep Apnea (OSA) is a prevalent sleep disorder marked by repeated episodes of partial or complete upper airway obstruction during sleep, which leads to intermittent hypoxia and fragmented sleep. These disruptions negatively impact cardiovascular health, metabolic function, and overall quality of life. Obesity is a major modifiable risk factor for OSA, as it contributes to both anatomical and physiological mechanisms that increase the likelihood of airway collapse during sleep. While continuous positive airway pressure (CPAP) therapy remains the gold standard for OSA treatment, its limitations - particularly issues with patient adherence - underscore the need for alternative or adjunct therapeutic options. One such option is the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs), which are widely recognized for their ability to reduce body weight and improve metabolic health. Emerging evidence suggests that GLP-1 RAs may offer therapeutic benefits in managing OSA, particularly by addressing obesity, a key contributor to the condition. This narrative review seeks to explore the role of GLP-1 RAs in the treatment of OSA, evaluating their efficacy in reducing OSA severity and discussing their broader clinical implications for future research and practice.

Video-assisted thoracoscopic surgery retrieval of a migrated unilateral hypoglossal nerve stimulator sensor lead

Obstructive sleep apnea is a common chronic condition typically treated with positive airway pressure. However, many patients have difficulty with adherence to this therapy, and for some, implantation of a hypoglossal nerve stimulator has become an option. Although device implantation is generally well-tolerated, a minority of patients will experience serious adverse events. Here we report the unusual complication of the sensor lead migrating to the costophrenic angle and invading the pleural space. Nine months after original implantation, the sensor lead malfunctioned and was found to be displaced. Initial explantation and reimplantation of a new device resulted in the inability to find a portion of the lead. Reimaging showed the missing lead at the costophrenic angle, and the patient underwent thoracoscopic removal. He resumed therapy with the new device without difficulty. This case demonstrates the ability of the lead to migrate far from the implantation site, which has rarely been reported.

CITATION

Rosen R, Padhya T, Daniel J, Sharma A. Video-assisted thoracoscopic surgery retrieval of a migrated unilateral hypoglossal nerve stimulator sensor lead. J Clin Sleep Med. 2024;20(11):1851-1855.

Comprehensive Analysis of Adverse Events Associated With Hypoglossal Nerve Stimulators: Insights From the MAUDE Database

OBJECTIVE

This study aims to examine the adverse events associated with hypoglossal nerve stimulator (HNS) implantation for treating obstructive sleep apnea (OSA), drawing data from the Manufacturer and User Facility Device Experience (MAUDE) database. We aim to provide a comprehensive and updated account of these adverse events.

STUDY DESIGN

Retrospective analysis.

SETTING

MAUDE Database review.

METHODS

A retrospective analysis was performed on the MAUDE database to collect all HNS-related reports from May 2014 to December 2023. Variables collected included date of event, event description, nature of event, iatrogenic injuries, required interventions, and, if available, root causes. Each event description was analyzed to classify the adverse event, the postevent intervention, and device model number.

RESULTS

Out of 1178 reports fulfilling the inclusion criteria, 1312 adverse events were identified. Common adverse events included infection (24.0%), pain (19.7%), and hematoma/seroma (10.2%). Approximately 83.1% of these adverse events necessitated medical and/or surgical intervention. The most frequent procedures included explantation (29.4%) and device repositioning (15.8%). Pneumothorax was reported in 50 cases, with 41 (82.0%) requiring a chest tube to be inserted. Three adverse events described overstimulation in the setting of magnetic resonance imaging (MRI) despite the implantation of MRI-compatible second-generation internal pulse generators.

CONCLUSION

While HNS implantation has been established as a reliable intervention for OSA in cases of continuous positive airway pressure failure or intolerance, this study highlights several perioperative and postoperative difficulties and complications. Understanding these challenges is essential for refining surgical practices and enhancing patient consent processes, ultimately aiming to improve therapeutic outcomes.

Outcomes and Predictors of Success Following Multilevel Surgery in Positional and Nonpositional Obstructive Sleep Apnea

OBJECTIVE

To assess the surgical outcomes and identify predictors of surgical success in patients with positional and non-positional obstructive sleep apnea following multilevel airway surgery.

STUDY DESIGN

Retrospective cohort study.

SETTING

Singe-tertiary medical center.

METHODS

This study included 158 patients with obstructive sleep apnea who underwent multilevel airway surgery. Patients were divided into 2 groups according to position dependency: "positional patients" group (n = 100), and "nonpositional patients" group (n = 58). The characteristics and surgical outcomes of the 2 groups were compared.

RESULTS

The nonpositional group included younger and more obese patients in comparison to the positional group. Moreover, the nonpositional group had more severe disease than the positional group. Both groups showed overall improvement after surgery, and the surgical success rate did not differ significantly between the 2 groups (nonpositional, 41.4% vs positional, 48.0%; P = .424). Notably, 69.0% of patients belonging to the non-positional group converted to positional group postoperatively. Logistic regression analysis revealed that larger tonsil size, female sex, and higher mean O2 saturation were associated with higher success rate in the positional group, whereas larger tonsil size was associated with surgical success in the nonpositional group.

CONCLUSION

Both nonpositional and positional groups showed improvements following multilevel airway surgery, and surgery induced a transition from nonpositional to positional group. Given that the factors related to surgical success differed between the two groups, surgeons should consider position dependency and these distinct factors during decision-making.

[Ten years of hypoglossal nerve stimulation in obstructive sleep apnea: a systematic literature review]

OBJECTIVE

To show the importance of hypoglossal nerve stimulation (HGNS) as a treatment method for obstructive sleep apnea (OSA) in the German healthcare context and to better assess the way patients who do not receive adequate care could benefit from HGNS.

METHODS

A systematic literature review in the Medline and Cochrane Library literature database was conducted, including publications using different stimulation technologies for HGNS. The efficacy of HGNS was assessed based on patient-relevant outcomes (daytime sleepiness, quality of life), treatment adherence and the apnea-hypopnea index (AHI) and oxygen desaturation index (ODI). The safety of the treatment method was assessed based on adverse events (AEs).

RESULTS

Inclusion and analysis of 33 publications: 2 randomized controlled trials (RCTs, level Ib), 1 level IIb trial (n = 1) and 30 level IV trials with a study duration of up to 60 months. The RCTs showed better values for daytime sleepiness and quality of life when using HGNS than in the control group. AHI and ODI showed a deterioration under placebo stimulation or therapy withdrawal in the RCTs. Consistently high adherence was also reported in the long-term course. Severe AEs under HGNS were rare and could usually be resolved by repositioning electrodes or replacing device components. Other AEs were mostly transient or could be resolved by non-invasive measures. All investigated parameters showed similar results in the evaluated studies. The results of different stimulation systems are comparable in type and extent.

CONCLUSION

The comprehensive review of the literature shows consistent data that highlight the importance of HGNS as an effective and safe treatment for OSA after unsuccessful CPAP treatment. The evaluation also shows that the different stimulation systems make it possible to better tailor the therapy to the patient's individual requirements. A future systematic evaluation of real-world data on the use of HGNS would help gain additional insights into the relevance of the method in routine clinical practice.

Personalized Treatment for Obstructive Sleep Apnea: Beyond CPAP

Obstructive sleep apnea (OSA) is a sleep disorder characterized by repetitive episodes of partial or complete obstruction of the upper airway during sleep. Continuous positive airway pressure (CPAP) is a method used as a first-line treatment for obstructive sleep apnea (OSA). However, intolerance and resistance to CPAP can limit its long-term effectiveness. Alternative treatments are available, such as Mandibular Advancement Devices (MADs), positional therapy, upper airway surgery, and maxillomandibular osteotomy. However, often less efficient in reducing the apnea-hypopnea index, the higher tolerance of and compliance to alternative treatment has resulted in the adequate treatment of OSA in CPAP-intolerant patients. This paper describes the protocol of a prospective single-center cohort study including adult patients with moderate to severe OSA (15 events/h ≤ apnea-hypopnea index (AHI) < 65 events/h) that failed to comply with CPAP therapy. Selected patients will be invited to the clinic to explore alternative treatment options where DISE will be a first step in further identifying upper airway collapse during sleep. By exploring alternative treatment options in CPAP-intolerant patients and systematically documenting their treatment paths, an algorithm can be defined to better guide patients towards personalized treatment for OSA. The follow-up is aimed at 5 years with an inclusion of 170 patients per year, including a drop-out rate of 15%. By leveraging a real-world database, this study aims to bridge the gap between research and clinical practice, facilitating the development of evidence-based guidelines and personalized treatment algorithms for CPAP-intolerant patients.

Effect of norepinephrine reuptake inhibitors combined with antimuscarinic agents vs monotherapy for OSA: a systematic review and meta-analysis

STUDY OBJECTIVES

Randomized controlled trials have shown that combining norepinephrine reuptake inhibitors and antimuscarinics can ameliorate the severity of obstructive sleep apnea. This article explores whether the effectiveness and safety of combining norepinephrine reuptake inhibitors with antimuscarinic agents surpass monotherapy for treating obstructive sleep apnea.

METHODS

We searched randomized controlled trials including adult patients with obstructive sleep apnea who received combination therapy and monotherapy in 8 databases from inception until April 5, 2023 and evaluated the studies' quality and conducted a meta-analysis and systematic review. The primary outcome was the apnea-hypopnea index. Secondary outcome measures included loop gain, hypoxic burden, oxygen desaturation index, and ventilation at low ventilatory drive, among other indicators. We assessed the quality of the studies using Cochrane Methods criteria.

RESULTS

We identified 4 randomized controlled trials for systematic review and 2 for meta-analysis. The results of the meta-analysis showed that norepinephrine reuptake inhibitors combined with antimuscarinic agents in patients with obstructive sleep apnea prolonged total sleep time by a mean of 28.20 minutes [95% confidence interval (5.78, 50.61), P = .01] and increased sleep efficiency by 4.73% [95% confidence interval (0.50, 8.97), P = .03] compared with norepinephrine reuptake inhibitors alone. Other indices and adverse events were of no statistical significance. The systematic reviews revealed that norepinephrine reuptake inhibitors combined with antimuscarinics may be superior to monotherapy in improving apnea-hypopnea index and endotypic traits.

CONCLUSIONS

This evaluation demonstrated the potential advantages of combining norepinephrine reuptake inhibitors plus antimuscarinics for treating OSA compared with norepinephrine reuptake inhibitors alone and revealed no statistically significant difference in drug safety.

CITATION

Wang J, Ye Y, Shang Z, et al. Effect of norepinephrine reuptake inhibitors combined with antimuscarinic agents vs monotherapy for OSA: a systematic review and meta-analysis. J Clin Sleep Med. 2024;20(8):1363-1372.

Oral appliance therapy and hypoglossal nerve stimulation as non-positive airway pressure treatment alternatives for obstructive sleep apnea: a narrative expert review

This perspective on alternatives to positive airway pressure (PAP) therapy for the treatment of obstructive sleep apnea (OSA) summarizes the proceedings of a focus group that was conducted by the Sleep Research Society Foundation. This perspective is from a multidisciplinary panel of experts from sleep medicine, dental sleep medicine, and otolaryngology that aims to identify the current role of oral appliance therapy and hypoglossal nerve stimulation for the treatment of OSA with emphasis on the US practice arena. A secondary aim is to identify-from an implementation science standpoint-the various barriers and facilitators for adoption of non-PAP treatment that includes access to care, multidisciplinary expertise, reimbursement, regulatory aspects, current treatment guidelines, health policies, and other factors related to the delivery of care. The panel has contextualized the review with recent events-such as a large-scale PAP device recall compounded by supply chain woes of the pandemic-and emerging science in the field of OSA and offers solutions for multidisciplinary approaches while identifying knowledge gaps and future research opportunities.

The Effects of Obstructive Sleep Apnea on the Cardiovascular System: A Comprehensive Review

Obstructive sleep apnea (OSA) is an increasingly relevant cause of cardiovascular morbidity worldwide. Although the association between OSA and the cardiovascular system is well-known, the extent of its effects is still a topic of interest, including pathophysiologic mechanisms, cardiovascular sequelae, and OSA therapies and their effects. Commonly described mechanisms of cardiovascular etiologies revolve around sympathetic activation, inflammation, and intermittent hypoxia resulting from OSA. Ultimately, these effects lead to manifestations in the cardiovascular system, such as arrhythmias, hypertension, and heart failure, among others. The resulting sequelae of OSA may also have differential effects based on gender and age; several studies suggest female gender to have more susceptibility to cardiovascular mortality, as well as an increase in age. Furthermore, several therapies for OSA, both established and emerging, show a reduction in cardiovascular morbidity and may even reduce cardiovascular burden. Namely, the establishment of CPAP has led to improvement in hypertension and cardiac function in patients with heart failure and even reduced the progression of early stages of atherosclerosis. Effective management of OSA decreases abnormal neural sympathetic activity, which results in better rhythm control and blood pressure control, both in waking and sleep cycles. With newer therapies for OSA, its effects on the cardiovascular system may be significantly reduced or even reversed after long-term management. The vast extent of OSA on the cardiovascular system, as well as current and future therapeutic strategies, will be described in detail in this review.

Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea in a Patient with Cerebral Palsy

INTRODUCTION

Obstructive sleep apnea (OSA) is common amongst patients with cerebral palsy in part due to significant hypotonia. Hypoglossal nerve stimulation (HGNS) is a novel tool used to treat sleep apnea when there is failure with CPAP. To our knowledge, the literature has not discussed HGNS as a treatment option for severe OSA in patients with cerebral palsy.

METHODS

Case report and literature review.

RESULTS

A 28-year-old male with cerebral palsy, neuromuscular deformity, proximal junction kyphosis, and developmental delay presented with severe obstructive sleep apnea and was intolerant to CPAP and BiPAP. After HGNS implantation, a sleep study revealed improved ventilation and oxygenation at 2.4 V; AHI decreased from baseline of 112 to 12 events per hour with only mild intermittent snoring. The patient's family reported increased utilization compared with previous CPAP use.

CONCLUSION

HGNS can be a safe and effective treatment modality for OSA in this patient population. Laryngoscope, 134:2478-2479, 2024.

Right Versus Left Cuff Position for Upper Airway Stimulation

OBJECTIVE

Upper airway stimulation (UAS) is a treatment option for obstructive sleep apnea in which electrical stimulation is applied to the hypoglossal nerve. Nerve branches that control tongue protrusion are located inferiorly. Due to positioning, left-sided implants are typically placed with an inferiorly oriented electrode cuff (L-down) as opposed to superiorly on the right (R-up). In this study, we assess the impact of left- versus right-sided UAS on patient outcomes.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary Academic Medical Center.

METHODS

Patients who underwent UAS implantation between 2016 and 2021 with an L-down or R-up oriented cuff as confirmed by X-ray were included. Data were collected retrospectively. Most recent sleep study variables were used for analysis.

RESULTS

A total of 190 patients met the inclusion criteria. The average age was 61.0 ± 11.0 years, with 55 (28.9%) females. L-down orientation was present in 21 (11.1%) patients vs 169 (88.9%) R-up. Indications for L-down included hunting/shooting (n = 15), prior radiation/surgery (n = 4), central port (n = 1), and brachial plexus injury (n = 1). Adherence was higher among L-down patients (47.1 vs 41.0 hours use/week, P = .037) in univariate analysis, with a similar time to adherence data collection (4.4 vs 4.2 months, P = .612), though this finding was not maintained in the multivariate regression analysis. Decrease in apnea-hypopnea index (21.3 vs 22.8, P = .734), treatment success (76.5% vs 84.0%, P = .665), functional threshold (1.5 vs 1.6, P = .550), therapeutic amplitude (2.3 vs 2.4, P = .882), and decrease in Epworth Sleepiness Scale (4.9 vs 2.6, P = .060) were not significantly different between cohorts.

CONCLUSION

This study is the first to examine the orientation of the UAS electrode cuff concerning the electrodes' natural position and the potential effect on postoperative outcomes. Our study found no significantly different treatment outcomes between the L-down versus R-up cohort, with the exception of device adherence, which was significantly higher in the L-down group on univariate analysis though not on multivariate analysis. Future studies with larger patient cohorts are needed to further investigate this potential relationship between treatment outcomes and electrode cuff orientation.

Surgical Management of Airway Stenosis During Pregnancy: A Scoping Review

OBJECTIVE

There are several options for surgical management of subglottic stenosis, including endoscopic and open procedures. However, treatment algorithms, outcomes, and anesthetic management of subglottic stenosis during pregnancy are not well described.

DATA SOURCES

MEDLINE, EMBASE, and the Cochrane databases.

REVIEW METHODS

A scoping review of management of subglottic stenosis during pregnancy was performed, and then reported in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Inclusion criteria consisted of those with subglottic or tracheal stenosis aged greater than 18 years, those in whom management was performed during pregnancy, and those who reported delivery related outcomes.

RESULTS

After systematic review and detailed search of 330 identified articles, 15 articles met inclusion criteria and were included in the final analysis. All studies were case reports or case series (level 4 evidence). This study identified 27 patients. The median age was 29 and the median gestational age at intervention was 28 weeks. Left lateral positioning and fetal heart rate monitoring were used in nearly every case. The most common intervention performed was endoscopic balloon dilation. In many cases, jet ventilation or transnasal humidified rapid insufflation ventilatory exchange was satisfactory for maintenance of the airway. Three women ultimately required tracheostomy prior to labor and delivery. There was no fetal death or complications reported in these studies, and all but one woman proceeded to deliver at term.

CONCLUSION

Endoscopic balloon dilation during pregnancy is safe and effective, resulting in optimized respiratory outcomes for the mother and safe delivery of the fetus. The third trimester appears to be safe for airway intervention. Laryngoscope, 134:1014-1022, 2024.

Advances in the Use of Hypoglossal Nerve Stimulator in Adolescents With Down Syndrome and Persistent Obstructive Sleep Apnea-A Systematic Review

INTRODUCTION

The Hypoglossal Nerve Stimulator (HNS) is a novel therapy that has been extensively studied in adults and more recently, it has been incorporated in children with Down Syndrome (DS) with persistent obstructive sleep apnea after adenotonsillectomy and trial of continuous positive airway pressure treatment. This systematic review article aims to examine the existing literature on HNS use in children to explore the benefits, efficacy, and parental experiences.

METHODS

MEDLINE, Web of Science and EMBASE were searched to include all studies published up to March 2nd, 2023, on the topic of HNS use in pediatric population under 21 years old.

RESULTS

A total of 179 studies were initially identified from which 10 articles were consistent with the inclusion criteria. Nine articles addressed outcomes after implantation of the HNS device in children with DS and 1 article explored the parental experiences. Findings were similar across studies where after implantation of HNS, there was marked improvement in polysomnographic outcomes and quality of life scores with high level of compliance.

CONCLUSIONS

HNS holds promise as an effective treatment option for pediatric patients with DS and persistent OSA after AT and CPAP trials. It significantly improves sleep-disordered breathing, quality of life, and neurocognitive measures, leading to substantial and sustained benefits for these children. While the findings are encouraging, further research is needed to explore the potential of HNS in other pediatric populations without DS and to raise awareness among healthcare providers about this treatment option. Overall, HNS may offer significant long-term benefits for the overall well-being and health of pediatric patients with DS and persistent OSA.

The Impact of Hypoglossal Nerve Stimulation on Secondary Health Outcomes

Objectives: Obstructive sleep apnea (OSA) is a prevalent sleep disorder that can increase the risk of hypertension, diabetes, obesity, and cardiovascular diseases. Hypoglossal nerve stimulation (HGNS) is an alternative therapy for OSA in patients who cannot tolerate continuous positive airway pressure. Understanding the impact of HGNS on blood pressure, hemoglobin A1C (A1C), and body mass index (BMI) currently remains limited. Methods: A retrospective review study of HGNS outcomes at a single practice from January 2020 to November 2022 was conducted. Inclusion/exclusion criteria were based on HGNS eligibility and postoperative titration study. Statistical analysis and data management were performed using statistical software, R (v.4.2.1; R Core Team). Paired Student's T test, Fisher's exact test, and McNemar's exact test were utilized for statistical analysis. P values less than .05 were considered statistically significant. Results: Sixty-three patients were included in this study. A significant decrease in mean apnea-hypopnea index was noted following HGNS (mean change -28; P < .0001). Similar significant decreases were also seen in mean arterial pressures (mean change -8.4, P < .0001). There was a significant change in overall antihypertensive medication requirements and in requirements ≥3 medications (P < .0005, P = .03). There was a trend toward reduction in A1C; however, there was no change in BMI or number of diabetes medications taken. Conclusions: Our results reinforce previous findings that HGNS is an effective treatment option for carefully selected patients with OSA. In addition, our findings suggest that HGNS may improve patients' quality of life while minimizing OSA associated morbidity.

Clinical efficacy and mechanism study of mid-frequency anti-snoring device in treating moderate obstructive sleep apnea-hypopnea syndrome

BACKGROUND

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is primarily caused by airway obstruction due to narrowing and blockage in the nasal and nasopharyngeal, oropharyngeal, soft palate, and tongue base areas. The mid-frequency anti-snoring device is a new technology based on sublingual nerve stimulation. Its principle is to improve the degree of oropharyngeal airway stenosis in OSAHS patients under mid-frequency wave stimulation. Nevertheless, there is a lack of clinical application and imaging evidence.

AIM

To investigate the clinical efficacy and mechanisms of a mid-frequency anti-snoring device in treating moderate OSAHS.

METHODS

We selected 50 patients diagnosed with moderate OSAHS in our hospital between July 2022 and August 2023. They underwent a 4-wk treatment regimen involving the mid-frequency anti-snoring device during nighttime sleep. Following the treatment, we monitored and assessed the sleep apnea quality of life index and Epworth Sleepiness Scale scores. Additionally, we performed computed tomography scans of the oropharynx in the awake state, during snoring, and while using the mid-frequency anti-snoring device. Cross-sectional area measurements in different states were taken at the narrowest airway point in the soft palate posterior and retrolingual areas.

RESULTS

Compared to pretreatment measurements, patients exhibited a significant reduction in the apnea-hypopnea index, the percentage of time with oxygen saturation below 90%, snoring frequency, and the duration of the most prolonged apnea event. The lowest oxygen saturation showed a notable increase, and both sleep apnea quality of life index and Epworth Sleepiness Scale scores improved. Oropharyngeal computed tomography scans revealed that in OSAHS patients cross-sectional areas of the oropharyngeal airway in the soft palate posterior area and retrolingual area decreased during snoring compared to the awake state. Conversely, during mid-frequency anti-snoring device treatment, these areas increased compared to snoring.

CONCLUSION

The mid-frequency anti-snoring device demonstrates the potential to enhance various sleep parameters in patients with moderate OSAHS, thereby improving their quality of life and reducing daytime sleepiness. These therapeutic effects are attributed to the device's ability to ameliorate the narrowing of the oropharynx in OSAHS patients.

Bioelectricity in dental medicine: a narrative review

BACKGROUND

Bioelectric signals, whether exogenous or endogenous, play crucial roles in the life processes of organisms. Recently, the significance of bioelectricity in the field of dentistry is steadily gaining greater attention.

OBJECTIVE

This narrative review aims to comprehensively outline the theory, physiological effects, and practical applications of bioelectricity in dental medicine and to offer insights into its potential future direction. It attempts to provide dental clinicians and researchers with an electrophysiological perspective to enhance their clinical practice or fundamental research endeavors.

METHODS

An online computer search for relevant literature was performed in PubMed, Web of Science and Cochrane Library, with the keywords "bioelectricity, endogenous electric signal, electric stimulation, dental medicine."

RESULTS

Eventually, 288 documents were included for review. The variance in ion concentration between the interior and exterior of the cell membrane, referred to as transmembrane potential, forms the fundamental basis of bioelectricity. Transmembrane potential has been established as an essential regulator of intercellular communication, mechanotransduction, migration, proliferation, and immune responses. Thus, exogenous electric stimulation can significantly alter cellular action by affecting transmembrane potential. In the field of dental medicine, electric stimulation has proven useful for assessing pulp condition, locating root apices, improving the properties of dental biomaterials, expediting orthodontic tooth movement, facilitating implant osteointegration, addressing maxillofacial malignancies, and managing neuromuscular dysfunction. Furthermore, the reprogramming of bioelectric signals holds promise as a means to guide organism development and intervene in disease processes. Besides, the development of high-throughput electrophysiological tools will be imperative for identifying ion channel targets and precisely modulating bioelectricity in the future.

CONCLUSIONS

Bioelectricity has found application in various concepts of dental medicine but large-scale, standardized, randomized controlled clinical trials are still necessary in the future. In addition, the precise, repeatable and predictable measurement and modulation methods of bioelectric signal patterns are essential research direction.

Controversies in Sleep Apnea

This chapter discusses controversies in diagnosis and management of obstructive sleep apnea (OSA), with particular focus on surgical management to improve quality of life. Though OSA is a complex disorder that affects millions of people worldwide, its management remains controversial among clinicians. Gaps in understanding its pathophysiology, long-term health consequences, diagnostic methods, and treatment strategies exist. While continuous positive airway pressure (CPAP) therapy is considered the gold standard for moderate to severe obstructive sleep apnea (OSA), its adherence rate is often low, and its efficacy in improving outcomes beyond symptom reduction and quality of life improvement is uncertain. As such, surgical intervention may be an alternative for specific patient populations. Additionally, the type of surgical intervention may depend on individual patient needs, anatomic features, as well as preferences.

Sleep Disorders and Aging in Women

Women of advancing age can suffer from an array of sleep disorders. We review the changes in sleep architecture, the impact of hormonal changes on sleep, and the various sleep disorders in women of advancing age. A focused history in this population should include the temporal relation to menopause and comorbid conditions. Treatment options should involve patient preference and review of current medications and comorbid conditions to optimize sleep in this population.

Increased Body Mass Index Correlates with Less Favorable Postoperative Outcomes After Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea: A Retrospective Cohort Study

OBJECTIVE

Obstructive sleep apnea is associated with high morbidity. Hypoglossal nerve stimulation (HNS) has become a novel (neuro-) surgical treatment strategy for obstructive sleep apnea, demonstrating good success rates. Beyond predefined inclusion and exclusion criteria, no precise data are available, enabling individual preoperative risk assessment. To improve preoperative risk stratification, this study analyzed individual patient factors that affect outcomes of HNS.

METHODS

Fourteen patients treated with unilateral HNS were analyzed retrospectively. Assessed risk factors included: hypertension, diabetes mellitus, depression, smoking, alcohol consumption, body mass index (BMI), and disease duration. Treatment success was defined as a reduction in the postoperative apnea-hypopnea index (AHI) to ≤20 events/hour, with a relative reduction of at least 50% compared to baseline.

RESULTS

A significant reduction in the postoperative apnea-hypopnea index was observed in all patients (P < 0.0001). BMI correlated significantly with postoperative AHI scores (95% confidence interval, 0.1519-0.8974; P = 0.018). Significant treatment success was observed in 50% of patients. Compared with the "Excellent Responder group," the "Responder group" demonstrated a significantly higher BMI (95% confidence interval, 1.174-6.226; P = 0.0078). Diabetes, hypertension, disease duration, smoking, depression, and alcohol consumption were not significantly associated with AHI reduction.

CONCLUSIONS

Our findings suggest that BMI may be an independent risk factor for the response to HNS, with patients who had less benefit from therapy having significantly higher BMI than "Excellent Responders." Therefore, carefully selecting patients is crucial in obtaining optimal outcomes with HNS therapy, especially those with a high BMI.

Sleep disorders in Lewy body dementia: Mechanisms, clinical relevance, and unanswered questions

In Lewy body dementia (LBD), disturbances of sleep and/or arousal including insomnia, excessive daytime sleepiness, rapid eye movement (REM) sleep behavior disorder, obstructive sleep apnea, and restless leg syndrome are common. These disorders can each exert a significant negative impact on both patient and caregiver quality of life; however, their etiology is poorly understood. Little guidance is available for assessing and managing sleep disorders in LBD, and they remain under-diagnosed and under-treated. This review aims to (1) describe the specific sleep disorders which occur in LBD, considering their putative or potential mechanisms; (2) describe the history and diagnostic process for these disorders in LBD; and (3) summarize current evidence for their management in LBD and consider some of the ongoing and unanswered questions in this field and future research directions.

Research trends and hotspots regarding treatment of obstructive sleep apnea

Background

Obstructive sleep apnea (OSA) is a type of sleep-disordered breathing disease, with high prevalence and multiple complications. It seriously affects patients' quality of life and even threatens their lives. Early and effective treatment can significantly improve patients' health conditions.

Objective

In this study, the main treatment methods, research hotspots and trends of OSA were summarized through bibliometric and visualization analysis.

Methods

From the Web of Science Core Collection database, articles on the treatment of OSA from 1999 to 2022 were obtained. CiteSpace and VOSviewer were comprehensively used to visualization of journals, co-authorship of countries, institutions and authors, co-citation of references, keywords cluster and burst.

Results

A total of 2,874 publications were obtained, of which 2,584 were concerned adults and 290 about children. In adults' research, Sleep and Breathing is the most published journal (280, 10.84%), the largest number of publications come from the United States (636,24.61%) and the University of Sydney (88, 3.41%), and Pepin JL is the most published author (48, 18.58%). In children's studies, International Journal of Pediatric Otorhinolaryngology is the most published journal (41, 14.14%), the maximum number of publications were also from the United States (123, 42.41%), with the University of Pennsylvania (20, 6.90%) and Marcus CL (15, 5.17%) being the most published institutions and authors. High-frequency keywords for adults' researches include positive airway pressure, oral appliance, surgery and positional therapy. On these basis, children's studies also focus on myofunctional therapy, rapid maxillary expansion and hypoglossal nerve Stimulation.

Conclusion

Over the past two decades, research in the field of OSA therapeutics has experienced significant growth in depth and breadth. The author cooperation network has already established a solid foundation, while there is potential for further strengthening the cooperation network between countries and institutions. Currently, positive airway pressure and surgery are the primary treatments for OSA in adults and children. Future research will focus on multidisciplinary combination targeted therapy, which presents a key area of interest and challenge.

Current state of the art and future directions for implantable sensors in medical technology: Clinical needs and engineering challenges

Implantable sensors have revolutionized the way we monitor biophysical and biochemical parameters by enabling real-time closed-loop intervention or therapy. These technologies align with the new era of healthcare known as healthcare 5.0, which encompasses smart disease control and detection, virtual care, intelligent health management, smart monitoring, and decision-making. This review explores the diverse biomedical applications of implantable temperature, mechanical, electrophysiological, optical, and electrochemical sensors. We delve into the engineering principles that serve as the foundation for their development. We also address the challenges faced by researchers and designers in bridging the gap between implantable sensor research and their clinical adoption by emphasizing the importance of careful consideration of clinical requirements and engineering challenges. We highlight the need for future research to explore issues such as long-term performance, biocompatibility, and power sources, as well as the potential for implantable sensors to transform healthcare across multiple disciplines. It is evident that implantable sensors have immense potential in the field of medical technology. However, the gap between research and clinical adoption remains wide, and there are still major obstacles to overcome before they can become a widely adopted part of medical practice.

Hypoglossal Nerve Stimulation as Treatment for Obstructive Apnea in a Patient with a Pharyngeal Flap

Hypoglossal nerve stimulation can be a successful form of treatment for obstructive sleep apnea in patients with a pharyngeal flap. Although the Inspire device is geared at relieving obstructive sleep apnea due to tongue base obstruction, it can still be highly efficacious in improving AHI and OSA symptoms in the presence of nasopharyngeal narrowing from the pharyngeal flap. Laryngoscope, 133:2428–2429, 2023

Medical Treatment of Obstructive Sleep Apnea in Children

Obstructive sleep apnea (OSA) is characterized by recurrent complete or partial obstruction of the upper airway. The prevalence is 1-4% in children aged between 2 and 8 years and rising due to the increase in obesity rates in children. Although persistent OSA following adenotonsillectomy is usually associated with obesity and underlying complex disorders, it can also affect otherwise healthy children. Medical treatment strategies are frequently required when adenotonsillectomy is not indicated in children with OSA or if OSA is persistent following adenotonsillectomy. Positive airway pressure treatment is a very effective modality for persistent OSA in childhood; however, adherence rates are low. The aim of this review article is to summarize medical treatment options for OSA in children.

Pathophysiological mechanisms and therapeutic approaches in obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) is a common breathing disorder in sleep in which the airways narrow or collapse during sleep, causing obstructive sleep apnea. The prevalence of OSAS continues to rise worldwide, particularly in middle-aged and elderly individuals. The mechanism of upper airway collapse is incompletely understood but is associated with several factors, including obesity, craniofacial changes, altered muscle function in the upper airway, pharyngeal neuropathy, and fluid shifts to the neck. The main characteristics of OSAS are recurrent pauses in respiration, which lead to intermittent hypoxia (IH) and hypercapnia, accompanied by blood oxygen desaturation and arousal during sleep, which sharply increases the risk of several diseases. This paper first briefly describes the epidemiology, incidence, and pathophysiological mechanisms of OSAS. Next, the alterations in relevant signaling pathways induced by IH are systematically reviewed and discussed. For example, IH can induce gut microbiota (GM) dysbiosis, impair the intestinal barrier, and alter intestinal metabolites. These mechanisms ultimately lead to secondary oxidative stress, systemic inflammation, and sympathetic activation. We then summarize the effects of IH on disease pathogenesis, including cardiocerebrovascular disorders, neurological disorders, metabolic diseases, cancer, reproductive disorders, and COVID-19. Finally, different therapeutic strategies for OSAS caused by different causes are proposed. Multidisciplinary approaches and shared decision-making are necessary for the successful treatment of OSAS in the future, but more randomized controlled trials are needed for further evaluation to define what treatments are best for specific OSAS patients.

Obstructive sleep apnoea-hypopnoea syndrome: state of the art

Obstructive sleep apnoea-hypopnoea syndrome (OSAHS) is an extremely common sleep-related breathing disorder (SRBD) characterised by complete or partial collapse of the upper airways. These nocturnal phenomena cause high-frequency hypoxemic desaturations (or intermittent hypoxia, IH) during sleep and alterations in gas exchange. The result of IH is the development or worsening of cerebro-cardio-vascular, metabolic and other diseases, which cause a high risk of death. Hence, OSAHS is a multifactorial disease affecting several organs and systems and presenting with various clinical manifestations involving different medical branches. Although it has been estimated that about one billion individuals worldwide are affected by OSAHS, this SRBD remains underestimated also due to misinformation regarding both patients and physicians. Therefore, this review aims to provide information on the main symptoms and risk factors for the detection of individuals at risk of OSAHS, as well as to present the diagnostic investigations to be performed and the different therapeutic approaches. The scientific evidence reported suggest that OSAHS is an extremely common and complex disorder that has a large impact on the health and quality of life of individuals, as well as on healthcare expenditure. Moreover, given its multifactorial nature, the design and implementation of diagnostic and therapeutic programmes through a multidisciplinary approach are necessary for a tailor-made therapy for each patient.

Short-Term Outcome of Unilateral Inspiration-Coupled Hypoglossal Nerve Stimulation in Patients with Obstructive Sleep Apnea

Hypoglossal nerve stimulation (HGNS) is a therapeutic option for patients with obstructive sleep apnea (OSA) and intolerance of positive airway pressure (PAP) therapy. Most reported data are based on multicentre pivotal trials with selected baseline core clinical features. Our aim was to investigate polysomnography (PSG)-based outcomes of HGNS-therapy in a patient cohort with higher average AHI and BMI than previously reported. Data of 29 consecutive patients (nine female; mean age: 55.52 ± 8.6 years, mean BMI 30.13 ± 3.93 kg/m²) were retrospectively evaluated. Numerical values of PSG- based metrics were compared before and after intervention using Wilcoxon's rank-sum test. AHI (38.57/h ± 12.71, 24.43/h ± 13.3, p < 0.001), hypopnea index (24.05/h ± 9.4, 15.27/h ± 8.23, p < 0.001), apnea index (14.5/h ± 12.05, 9.17/h ± 10.86, p < 0.01), snoring index (262.68/h ± 170.35, 143.48/h ± 162.79, p < 0.001), cortical arousal index (20.8/h ± 10.34 vs. 14.9/h ± 8.36, p < 0.01) and cumulative duration of apnea and hypopnea during sleep (79.79 min ± 40.32 vs. 48.62 min ± 30.56, p < 0.001) were significantly lower after HGNS. HGNS provides an effective therapy option for selected patients not tolerating PAP-therapy with higher average AHI and BMI than usually reported. HGNS-therapy appears to suppress central nervous system arousal circuits while not eliciting peripheral autonomous sympathetic activation. Such metrics as the snoring index and the cumulative duration of respiratory events during sleep may be considered in future HGNS studies.

Maxillomandibular Advancement and Upper Airway Stimulation for Treatment of Obstructive Sleep Apnea: A Systematic Review

This systematic review aimed to comparatively evaluate the efficacy and safety of maxillomandibular advancement (MMA) and upper airway stimulation (UAS) in obstructive sleep apnea (OSA) treatment. A MEDLINE and Embase database search of articles on MMA and/or UAS for OSA was conducted. Twenty-one MMA studies and nine UAS studies were included. All the MMA studies demonstrated a reduction in apnea hypopnea index (AHI) postoperatively, and success rates ranged from 41.1% to 100%. Ten MMA studies reported pre- and postoperative Epworth sleepiness scale (ESS), and all but one study demonstrated a reduction in ESS. In the UAS studies, all but one demonstrated a reduction in AHI, and success rates ranged from 26.7% to 77.8%. In the eight UAS studies reporting pre- and postoperative ESS, an ESS reduction was demonstrated. No studies reported any deaths related to MMA or UAS. The most common postoperative complications after MMA and UAS were facial paresthesia in the mandibular area and discomfort due to electrical stimulation, respectively. This systematic review suggests that both MMA and UAS are effective and generally safe therapies for OSA. However, due to the limitations of the included studies, there is no evidence yet to directly compare these two procedures in OSA treatment.

Transcutaneous electrical stimulation in obstructive sleep apnoea: current developments and concepts of the TESLA-home programme

PURPOSE OF REVIEW

Obstructive sleep apnoea (OSA) is a highly prevalent condition affecting about 1 billion people worldwide. The first line therapy for most patients with OSA is continuous positive airway pressure (CPAP) therapy. However, there are significant limitations with long-term adherence to CPAP therapy, which may be as low as 30-60%.

RECENT FINDING

Electrical stimulation of the hypoglossal nerve has been studied in recent years. It achieves upper airway patency by causing a contraction of the genioglossus muscle, the strongest dilator of the upper airway, and by maintaining its neuromuscular tone in the asleep patient with OSA. Electrical stimulation can be delivered invasively, hypoglossal nerve stimulation (HNS), and noninvasively, transcutaneous electrical stimulation in OSA (TESLA). However, randomised controlled trials, the STAR and the TESLA trial, have provided promising results on efficacy and safety of the methods.

SUMMARY

Patient and public involvement underlines the interest in TESLA and HNS and highlights the need to provide non-CPAP therapeutic options to those who may find it difficult to cope with first line therapies. The relatively low costs and the favourable safety profile of the TESLA approach provide the chance to offer this treatment to patients with OSA following further development of the evidence.

Treatment options in obstructive sleep apnea

Treatment of OSA with CPAP is currently the recommended treatment and has the greatest evidence of efficacy on AHI, symptoms and comorbidities. Symptomatic patients with moderate-severe OSA generally have good adherence to CPAP therapy, while those with mild OSA, female, young and generally paucisymptomatic, have lower CPAP adherence, especially in the medium and long term. The recent identification of different clinical and pathophysiological phenotypes of OSA has paved the way for alternative treatments to CPAP, leading to an increasingly personalized therapy. Weight loss and lifestyle modifications are highly recommended in all obese or overweight patients. Mandibular advancement devices (MAD), positional therapy (PT) and hypoglossal nerve stimulation (HSN) are recent and personalized alternative therapies on which there is promising and encouraging data but with still little strong scientific evidence. The purpose of this review is to compare the efficacy, adherence and costs of various therapeutic options for OSA patients in the light of recent evidence and to provide useful guidance for specialists.

Obstructive Sleep Apnea Syndrome: From Symptoms to Treatment

Obstructive sleep apnea (OSA) syndrome is a respiratory sleep disorder characterized by partial or complete recurrent episodes of upper airway collapse that occur during the night. The OSA manifests with a reduction (hypopnea) or complete cessation (apnea) of airflow in the upper airways, associated with breathing effort. OSA is a frequent and often underestimated pathology affecting between 2 and 5% of the middle-aged population. Typical nocturnal symptoms are the persistent snoring and awakenings with dyspnea sensation. On the other hand, diurnal symptoms could be sleepiness, headaches, asthenia, neurological disorders, and impaired personal relationships. Surgery of the velo-pharyngeal region had a huge evolution going from ablative techniques (UP3 and LAUP) to remodeling techniques of the pharyngeal lateral walls.

Hypoglossal Nerve Stimulation Therapy

Hypoglossal nerve stimulation (HNS) has been shown to be a safe alternative in the treatment of moderate-to-severe obstructive sleep apnea (OSA). A recent meta-analysis of 12 studies by Costantino et al. indicated the surgical success rates at 55-75%, a reduction of the apnea hypopnea index (AHI) of 18 events/h, and a reduction of the Epworth Sleepiness Scale (ESS) of 2.9-5.3. After animal studies in the 1970s, the first trial on humans to decrease upper airway resistance by transcutaneous electrical stimulation of the genioglossus was reported in 1989. A separate stimulation of protruding and retracting muscles was realized in 1995 by fine-wire electrodes that were placed into the tongue transoral. Over the next years, several companies developed implantable devices for hypoglossal stimulation in OSA. Initially, devices were developed that used unilateral stimulation of the hypoglossal nerve. In 2014, a device for unilateral respiratory frequency-controlled hypoglossal stimulation finally received FDA approval after a successful phase III trial. In recent years, a device for bilateral breath rate-independent stimulation of the hypoglossal nerve has been added to these approaches as a new development. Accordingly, hypoglossal nerve stimulation, on the one hand, is now an established tool for patients with OSA when standard treatments are not satisfactory. Beyond that, hypoglossal stimulation is undergoing a continuous and impressive development like hardly any other field of surgical therapy for OSA.

Anesthetic Management of a Patient With an Implantable Hypoglossal Nerve Stimulator: A Case Report

Obstructive sleep apnea (OSA) is a common condition, particularly in obese men and in those with an increased neck circumference. Management with a continuous positive airway pressure (CPAP) machine has been the mainstay of treatment over many years; although, it is not acceptable to all. Recently, innovative medical devices, such as hypoglossal nerve stimulators, have emerged and are now being increasingly utilized. We present a case report of a patient undergoing rotator cuff repair on the same side as the implanted device and our recommendations on the anesthetic management.