Mechanisms of Pharyngeal Collapse in Sleep Apnea, Study B

This study is currently recruiting participants. (see Contacts and Locations)
Verified September 2013 by Brigham and Women's Hospital
Sponsor:
Collaborator:
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 ] [ Designated as safety issue: No ]

    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
Genders Eligible for Study:   Both
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
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01738009

Contacts
Contact: Pedro R Genta, MD (617) 732-6541 pgenta@partners.org
Contact: Lauren B Hess, BS (617) 732-8976 lhess1@partners.org

Locations
United States, Massachusetts
Brigham and Women's Hospital Recruiting
Boston, Massachusetts, United States, 02115
Contact: Pedro R Genta, MD    617-732-6541    pgenta@partners.org   
Contact: Lauren B Hess, BS    (617) 732-8976    lhess1@partners.org   
Sub-Investigator: Pedro R Genta, MD         
Sponsors and Collaborators
Brigham and Women's Hospital
Investigators
Principal Investigator: David A Wellman, MD Brigham and Women's Hospital
  More Information

No publications provided

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
Health Authority: United States: Institutional Review Board

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

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

ClinicalTrials.gov processed this record on August 20, 2014