<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT01733784</url>
  </required_header>
  <id_info>
    <org_study_id>2012P000957D</org_study_id>
    <secondary_id>1R01HL102321-01A1</secondary_id>
    <nct_id>NCT01733784</nct_id>
  </id_info>
  <brief_title>Mechanisms of Pharyngeal Collapse in Sleep Apnea, Study D</brief_title>
  <official_title>Mechanisms of Pharyngeal Collapse in Sleep Apnea, Study D</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Brigham and Women's Hospital</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>National Heart, Lung, and Blood Institute (NHLBI)</agency>
      <agency_class>NIH</agency_class>
    </collaborator>
  </sponsors>
  <source>Brigham and Women's Hospital</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      In obstructive sleep apnea (OSA), the upper airway recurrently closes during sleep. The&#xD;
      mechanisms that lead to airway closure are not completely understood. Some studies have shown&#xD;
      that there is progressive narrowing of the pharyngeal airway across breaths during expiration&#xD;
      (Progressive Expiratory Narrowing, PEN) preceding an obstructive apnea. The investigators&#xD;
      will assess the viscoelastic properties of the pharyngeal airway and its role in PEN.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      In obstructive sleep apnea, the upper airway recurrently closes during sleep. The mechanisms&#xD;
      that lead to airway closure are not completely understood. Some studies have shown that there&#xD;
      is progressive narrowing of the pharyngeal airway across breaths during expiration&#xD;
      (Progressive Expiratory Narrowing, PEN) preceding an obstructive apnea.&#xD;
&#xD;
      The investigators will test how the viscoelastic properties of the airway influence PEN. To&#xD;
      this end, the investigators will visualize the pharynx of sleep apnea patients using a thin&#xD;
      endoscope and will induce central apneas during sleep. Pharyngeal cross-sectional area will&#xD;
      be recorded during incremental changes in pharyngeal pressure during central apneas.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Withdrawn</overall_status>
  <start_date type="Actual">December 8, 2012</start_date>
  <completion_date type="Actual">February 7, 2017</completion_date>
  <primary_completion_date type="Actual">February 7, 2017</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>N/A</allocation>
    <intervention_model>Single Group Assignment</intervention_model>
    <primary_purpose>Other</primary_purpose>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Upper airway elasticity</measure>
    <time_frame>10 - 40 seconds</time_frame>
    <description>The investigators will determine elasticity of the upper airway during induced central apneas by dividing the change in airway pressure by the change in airway cross-sectional area.&#xD;
The time frame for the outcome of this study is equal to the duration of the induced central sleep apnea (usually less than 40 seconds).</description>
  </primary_outcome>
  <number_of_arms>1</number_of_arms>
  <enrollment type="Actual">0</enrollment>
  <condition>Sleep Apnea</condition>
  <arm_group>
    <arm_group_label>Viscoelastic properties of the airway</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
  </arm_group>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Induced central apneas</intervention_name>
    <arm_group_label>Viscoelastic properties of the airway</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Normal subjects or patients with OSA&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Any unstable cardiac condition (other than well controlled hypertension) or pulmonary&#xD;
             problems.&#xD;
&#xD;
          -  Any medication known to influence breathing, sleep/arousal or muscle physiology&#xD;
&#xD;
          -  Concurrent sleep disorders (insomnia, narcolepsy, central sleep apnea or parasomnia)&#xD;
&#xD;
          -  Claustrophobia&#xD;
&#xD;
          -  Inability to sleep supine&#xD;
&#xD;
          -  Allergy to lidocaine or oxymetazoline hydrochloride&#xD;
&#xD;
          -  For women: Pregnancy&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>21 Years</minimum_age>
    <maximum_age>65 Years</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>David A Wellman, MD</last_name>
    <role>Principal Investigator</role>
    <affiliation>Brigham and Women's Hospital</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Brigham and Women's Hospital</name>
      <address>
        <city>Boston</city>
        <state>Massachusetts</state>
        <zip>02115</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <verification_date>July 2019</verification_date>
  <study_first_submitted>November 14, 2012</study_first_submitted>
  <study_first_submitted_qc>November 26, 2012</study_first_submitted_qc>
  <study_first_posted type="Estimate">November 27, 2012</study_first_posted>
  <last_update_submitted>July 9, 2019</last_update_submitted>
  <last_update_submitted_qc>July 9, 2019</last_update_submitted_qc>
  <last_update_posted type="Actual">July 11, 2019</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Brigham and Women's Hospital</investigator_affiliation>
    <investigator_full_name>David Andrew Wellman</investigator_full_name>
    <investigator_title>Principal Investigator</investigator_title>
  </responsible_party>
  <keyword>Sleep Apnea</keyword>
  <keyword>Pathophysiology</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Apnea</mesh_term>
    <mesh_term>Sleep Apnea Syndromes</mesh_term>
  </condition_browse>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT01733784
org study id: 2012P000957D
secondary id: 1R01HL102321-01A1
nct id: NCT01733784
lead sponsor: 
collaborator: 
has dmc: No
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 investigators
      will assess the viscoelastic properties of the pharyngeal airway and its role in PEN.
In obstructive sleep apnea, 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 investigators will test how the viscoelastic properties of the airway influence PEN. To
      this end, the investigators will visualize the pharynx of sleep apnea patients using a thin
      endoscope and will induce central apneas during sleep. Pharyngeal cross-sectional area will
      be recorded during incremental changes in pharyngeal pressure during central apneas.
allocation: N/A
intervention model: Single Group Assignment
primary purpose: Other
masking: None (Open Label)
measure: Upper airway elasticity
time frame: 10 - 40 seconds
description: The investigators will determine elasticity of the upper airway during induced central apneas by dividing the change in airway pressure by the change in airway cross-sectional area.
The time frame for the outcome of this study is equal to the duration of the induced central sleep apnea (usually less than 40 seconds).
arm group label: Viscoelastic properties of the airway
arm group type: Experimental
intervention type: Other
intervention name: Induced central apneas
arm group label: Viscoelastic properties of the airway
criteria: 
gender: All
minimum age: 21 Years
maximum age: 65 Years
healthy volunteers: No
last name: David A Wellman, MD
role: Principal Investigator
affiliation: Brigham and Women's Hospital
facility: 
country: United States
responsible party type: Principal Investigator
investigator affiliation: Brigham and Women's Hospital
investigator full name: David Andrew Wellman
investigator title: Principal Investigator
mesh term: Apnea
mesh term: Sleep Apnea Syndromes