Mechanisms of Pharyngeal Collapse in Sleep Apnea, Study B

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified September 2013 by Brigham and Women's Hospital.
Recruitment status was:  Recruiting
Sponsor:
Collaborator:
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
David Andrew Wellman, Brigham and Women's Hospital
ClinicalTrials.gov Identifier:
NCT01738009
First received: November 14, 2012
Last updated: September 25, 2013
Last verified: September 2013
  Purpose
In obstructive sleep apnea (OSA), the upper airway recurrently closes during sleep. The mechanisms that lead to airway closure are not completely understood. Some studies have shown that there is progressive narrowing of the pharyngeal airway across breaths during expiration (Progressive Expiratory Narrowing, PEN) preceding an obstructive apnea. The cause of PEN is unknown. The investigators will test if lung volumes and low respiratory drive play a role in PEN.

Condition Intervention
Sleep Apnea
Other: Induction of flow limitation

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Open Label
Official Title: Mechanisms of Pharyngeal Collapse in Sleep Apnea, Study B

Resource links provided by NLM:


Further study details as provided by Brigham and Women's Hospital:

Primary Outcome Measures:
  • Difference in peak inspiratory flow [ Time Frame: 3 minutes ]

    Measured peak inspiratory flow will be compared to predicted peak inspiratory flow during flow restricted breaths.

    The time frame for the outcome will be the duration of induced flow limitation (3 minutes each) . Flow limitation will be induced several times during the night. Flow limited breaths will be averaged.



Estimated Enrollment: 40
Study Start Date: December 2012
Estimated Study Completion Date: December 2014
Estimated Primary Completion Date: December 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Induction of flow limitation
Flow limitation will be induced by sustained reductions in continuous positive airway pressure during sleep
Other: Induction of flow limitation

Detailed Description:

The mechanisms that lead to airway closure in OSA are not completely understood. Some studies have shown that there is progressive narrowing of the pharyngeal airway across breaths during expiration (Progressive Expiratory Narrowing, PEN) preceding an obstructive apnea.

The investigators will test if lung volumes and low respiratory drive play a role in PEN. To this end, the investigators will visualize the pharynx of sleep apnea patients during sleep using a thin endoscope during sleep while simultaneously measuring lung volumes, genioglossus electromyogram, and pharyngeal pressure during flow-limited breaths. Flow limitation will be induced by sustained reductions of continuous positive airway pressure (CPAP).

  Eligibility

Ages Eligible for Study:   21 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Normal subjects or patients with OSA

Exclusion Criteria:

  • Any unstable cardiac condition (other than well controlled hypertension) or pulmonary problems.
  • Any medication known to influence breathing, sleep/arousal or muscle physiology
  • Concurrent sleep disorders (insomnia, narcolepsy, central sleep apnea or parasomnia)
  • Claustrophobia
  • Inability to sleep supine
  • Allergy to lidocaine or oxymetazoline hydroclhoride
  • For women: Pregnancy
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01738009

Locations
United States, Massachusetts
Brigham and Women's Hospital
Boston, Massachusetts, United States, 02115
Sponsors and Collaborators
Brigham and Women's Hospital
National Heart, Lung, and Blood Institute (NHLBI)
Investigators
Principal Investigator: David A Wellman, MD Brigham and Women's Hospital
  More Information

Responsible Party: David Andrew Wellman, Principal Investigator, Brigham and Women's Hospital
ClinicalTrials.gov Identifier: NCT01738009     History of Changes
Other Study ID Numbers: 2012P000957B  1R01HL102321-01A1 
Study First Received: November 14, 2012
Last Updated: September 25, 2013

Keywords provided by Brigham and Women's Hospital:
Sleep Apnea
Pathophysiology

Additional relevant MeSH terms:
Sleep Apnea Syndromes
Apnea
Respiration Disorders
Respiratory Tract Diseases
Sleep Disorders, Intrinsic
Dyssomnias
Sleep Wake Disorders
Nervous System Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms

ClinicalTrials.gov processed this record on January 23, 2017