Ansa Cervicalis and Hypoglossal Nerve Stimulation in Obstructive Sleep Apnea
Trial Snapshot
- Phase
- Not Applicable
- Status
- Recruiting
- Enrollment
- 100
- Locations
- 2
- Primary Endpoint
- Basic physiologic measurements during Drug Induced Sleep Endoscopy (DISE) - Airway cross sectional diameter
Study Overview
Brief Summary
Polysomnography (PSG) and drug-induced sleep endoscopy (DISE) are widely used diagnostic studies for assessing obstructive sleep apnea (OSA) severity and collapse patterns of the upper airway anatomy during sleep. Hypoglossal nerve stimulation (HNS) therapy for obstructive sleep apnea suffers from variable response at the level of the soft palate. The Investigators propose a study examining the physiologic effect of ansa cervicalis stimulation (ACS) alone and in combination with HNS during PSG and DISE.
Detailed Description
Obstructive Sleep Apnea (OSA) is a common disorder characterized by repetitive upper airway collapse during inspiration caused, in part, by a loss of neuromotor tone in specific upper airway muscles, with multiple associated health sequelae impacting millions of Americans. Patient adherence to the reference treatment, positive airway pressure (PAP), remains problematic. Despite the recent promising development of hypoglossal nerve stimulation (HNS) as a surgical therapy, its indications are limited and a proportion of eligible patients do not achieve sufficient response, leaving a critical unmet need for effective therapeutic alternatives to PAP.
This project challenges the long-held concept that the genioglossus muscle is primarily responsible for the maintenance of pharyngeal patency during sleep and proposes a novel therapeutic mechanism. It is built upon strong evidence that caudal pharyngeal traction from the trachea has a marked impact on pharyngeal patency primarily mediated through changes in lung volume. Contraction of the sternothyroid muscle, an infrahyoid cervical strap muscle that inserts onto the thyroid cartilage, also generates caudal pharyngeal traction. Our data suggest that ansa cervicalis stimulation (ACS) of the sternothyroid muscle unfolds and stretches the lateral pharyngeal walls and tensions the distal edge of the soft palate caudally, increasing airway patency.
The major hypothesis of the Investigators is that ACS overcomes specific anatomic and neuromuscular defects of upper airway control that restore pharyngeal patency in patients with OSA. This hypothesis is supported by published and preliminary data demonstrating that: (1) the degree of end-expiratory lung volume decrease in sleep correlates with observed increases in pharyngeal collapsibility, and (2) unilateral ACS increases maximum inspiratory airflow and velopharyngeal cross-sectional area during flow-limited breathing in sedated humans. These findings suggest that (3) tracheal traction, as mediated by end-expiratory lung volume (EELV), is a major contributor to airway patency in sleep. In this project, the Investigators will elucidate specific mechanisms for control of pharyngeal patency with caudal traction during drug-induced sleep endoscopy (DISE) and natural sleep (PSG). The Investigators will address these aims by characterizing (1) the effects of ACS of the sternothyroid muscle(s) on upper airway pressure-area and pressure-flow relationships, and (2) determine how subject anatomic, physiologic, and polysomnographic characteristics modulate these responses.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Basic Science
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Consenting adults with BMI≥ 25 and ≤ 40 kg/m2
- •Obstructive sleep apnea with an AHI between 20 and 80 events/hr (with hypopneas defined by 4% oxyhemoglobin desaturations); ≥80% obstructive events.
Exclusion Criteria
- •Chronic use of opiate medications, illicit drug use, or alcohol dependency
- •Other known concomitant sleep disorder (e.g., central sleep apnea, periodic limb movements, narcolepsy)
- •Clinical history or evidence of cardiopulmonary disease (or oxygen use), liver, renal, immunodeficiency, neurodegenerative diseases, or previous adverse reactions to anesthesia.
- •Prior upper airway reconstructive surgery excluding tonsillectomy (e.g., cleft palate repair, uvulopalatopharyngoplasty)
- •Indwelling neurostimulation device (e.g. cardiac pacemaker, spinal, vagal, or hypoglossal nerve stimulator)
Arms & Interventions
Muscle stimulation
Consented participants who meet eligibility will have a drug induced sleep endoscopy (DISE) and second sleep study and the Grass S88 (or comparable) muscle stimulator.
Intervention: Grass S88 Muscle Stimulator (Device)
Outcomes
Primary Outcomes
Basic physiologic measurements during Drug Induced Sleep Endoscopy (DISE) - Airway cross sectional diameter
Time Frame: During DISE, approximately 15 minutes
Airway cross-sectional diameter (mm\^2) will be measured throughout the operative procedure via flexible fiberoptic nasopharyngoscopy.
Basic physiologic measurements during Polysomnography (PSG) - Airflow data
Time Frame: During sleep study exam (PSG), approximately 8 hours
Airflow data (L/min) will be measured during the sleep study via a pneumotachometer applied to the nose.
Basic physiologic measurements during Polysomnography (PSG) - Electroocoulogram (EOG)
Time Frame: During sleep study exam (PSG), approximately 8 hours
EOG (mV) will be collected during the sleep study via skin surface electrodes.
Basic physiologic measurements during Polysomnography (PSG) - Respiratory effort data
Time Frame: During sleep study exam (PSG), approximately 8 hours
Respiratory effort data (mV) will be collected during the sleep study via respiratory inductance plethysmography.
Basic physiologic measurements during Drug Induced Sleep Endoscopy (DISE) - Airflow data
Time Frame: During DISE, approximately 15 minutes
Airflow data (L/min) will be measured throughout the operative procedure via a pneumotachometer applied to the nose.
Basic physiologic measurements during Polysomnography (PSG) - Electroencephalogram (EEG)
Time Frame: During sleep study exam (PSG), approximately 8 hours
EEG (mV) will be collected during the sleep study via skin surface electrodes.
Basic physiologic measurements during Polysomnography (PSG) - Video data
Time Frame: During sleep study exam (PSG), approximately 8 hours
Video data will be collected during the sleep study via in-room camera.
Basic physiologic measurements during Drug Induced Sleep Endoscopy (DISE) - Upper airway pressure changes
Time Frame: During DISE, approximately 15 minutes
Upper airway pressure changes (cmH20) will be measured throughout the operative procedure via a pneumotachometer applied to the nose.
Basic physiologic measurements during Drug Induced Sleep Endoscopy (DISE) - Respiratory effort data
Time Frame: During DISE, approximately 15 minutes
Respiratory effort data (mV) will be measured throughout the operative procedure via two respiratory inductance plethysmography belts.
Basic physiologic measurements during Polysomnography (PSG) - Electrocardiogram (EKG)
Time Frame: During sleep study exam (PSG), approximately 8 hours
EKG (mV) will be collected during the sleep study via skin surface electrodes.
Basic physiologic measurements during Polysomnography (PSG) - Electromyography (EMG)
Time Frame: During sleep study exam (PSG), approximately 8 hours
EMG data (mV) will be collected during the sleep study via skin surface electrodes.
Secondary Outcomes
- Amount of current needed for adequate stimulation(Collected during operative and sleep study procedures, taking about 15 minutes.)
Investigators
David Kent
Assistant Professor, Department of Otolaryngology-Head and Neck Surgery
Vanderbilt University Medical Center