<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/NCT01672242</url>
  </required_header>
  <id_info>
    <org_study_id>HP-00052656</org_study_id>
    <nct_id>NCT01672242</nct_id>
  </id_info>
  <brief_title>Assessment of End Expiratory Lung Volumes in Healthy Subjects Using High Flow Oxygen (Vapotherm®)</brief_title>
  <official_title>Assessment of End Expiratory Lung Volumes in Healthy Subjects Using High Flow Oxygen (Vapotherm®)</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University of Maryland, Baltimore</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Vapotherm, Inc.</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
  </sponsors>
  <source>University of Maryland, Baltimore</source>
  <oversight_info>
    <has_dmc>Yes</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Respiratory distress is a common problem in an intensive care unit. There are multiple&#xD;
      mechanisms that are used to help patients who are in respiratory distress including&#xD;
      mechanical ventilation, continuous positive airway pressure (CPAP), bilevel positive airway&#xD;
      pressure (BiPAP), high flow oxygen, and oxygen supplementation through nasal cannula or a&#xD;
      facemask.&#xD;
&#xD;
      The purpose of this study is to evaluate the mechanism by which Vapotherm, a high flow oxygen&#xD;
      system, provides breathing support. Vapotherm provides high flow oxygen at different flow&#xD;
      rates, meaning one can increase the amount of oxygen flow to help with breathing support. The&#xD;
      investigators believe that this high flow oxygen system may provide similar breathing support&#xD;
      that a continuous positive airway pressure machine (CPAP) machine does.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      High flow nasal cannula oxygen therapy (HFNC) is a method of oxygen delivery now commonly&#xD;
      used in persistently hypoxic patients refractory to conventional modes of oxygen&#xD;
      supplementation (i.e. nasal cannula, facemask, non-rebreather facemask). Initially used in&#xD;
      neonates, it is now increasingly popular in the adult population. While the investigators&#xD;
      know how HFNC provides oxygen supplementation, the physiologic mechanism of correcting&#xD;
      hypoxemia is still unclear. There are five mechanisms of hypoxemia, four which correct with&#xD;
      oxygen supplementation - decreased fraction of inspired oxygen (FiO2), hyperventilation,&#xD;
      ventilation-perfusion (V/Q) mismatch, and diffusion defect; and one that does not - shunt.&#xD;
      The hypoxemia refractory to supplemental oxygen suggests the presence of physiologic shunt.&#xD;
      The conventional non-invasive therapy to reduce shunt fraction requires raising&#xD;
      end-expiratory lung volumes by raising end-expiratory airway pressures using the application&#xD;
      of continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP).&#xD;
      The Vapotherm® (Vapotherm®, Stevensville, Maryland) product of high flow oxygen therapy&#xD;
      (Precision Flow®) is one the investigators frequently use in intensive care units at the&#xD;
      University of Maryland Medical Center. It does not create a leak proof seal in the nose as&#xD;
      seen in CPAP and BiPAP. Positive pressure generation has been studied in another high flow&#xD;
      oxygen system called Optiflow™ (Fisher &amp; Paykel Healthcare, Ltd., Auckland, New Zealand).&#xD;
      However this device differs from Vapotherm® in that its nasal bores are large and create a&#xD;
      seal in each nares thereby affected both ventilation and the level of positive end expiratory&#xD;
      pressure (PEEP) generation. Additionally, these studies measured positive expiratory lung&#xD;
      pressures, not volume. Positive end expiratory alveolar pressure and increase expiratory lung&#xD;
      volumes in adults have not yet been demonstrated using Precision Flow®.&#xD;
&#xD;
      HFNC is intriguing because studies and clinical data have shown it is a relatively&#xD;
      non-invasive method of oxygen delivery that appears to correct hypoxemia better than other&#xD;
      non-invasive methods. It is more comfortable than a CPAP machine and thus is better tolerated&#xD;
      among patients, especially those who are critically ill and possibly altered. While it has&#xD;
      been used in neonates for some time, its use with adults is new and needs more research.&#xD;
&#xD;
      The investigators hypothesis is that HFNC corrects persistent hypoxemia by producing&#xD;
      increased end-expiratory lung volumes thus keeping alveoli open throughout the respiratory&#xD;
      cycle which other oxygen supplements are unable to do. Using healthy volunteers the&#xD;
      investigators will measure end expiratory lung volumes on HFNC and compare them to those&#xD;
      obtained with CPAP at graded pressures.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>July 2012</start_date>
  <completion_date type="Actual">April 2014</completion_date>
  <primary_completion_date type="Actual">April 2014</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Crossover Assignment</intervention_model>
    <primary_purpose>Basic Science</primary_purpose>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Change in End-expiratory Lung Volume</measure>
    <time_frame>baseline and after 3-5 minutes after each level of flow or pressure</time_frame>
    <description>Change in end-expiratory lung volume from baseline arbitrarily set at 0 mL.</description>
  </primary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Actual">6</enrollment>
  <condition>Healthy Adult Volunteers</condition>
  <arm_group>
    <arm_group_label>HFNC</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>High Flow Nasal Cannula (HFNC) oxygen.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>CPAP</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Continuous Positive Airway Pressure (CPAP)</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>HFNC</intervention_name>
    <description>Graded high flow nasal cannula oxygen at 10, 20 , 30, and 40 liters per minute (LPM) to each subject and end-expiratory lung volume measured by respiratory inductive plethysmography.</description>
    <arm_group_label>HFNC</arm_group_label>
    <other_name>High flow nasal cannula oxygen, Precision Flow®, Vapotherm®</other_name>
  </intervention>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>CPAP</intervention_name>
    <description>Graded contiuous positive airway pressure at 5, 10 , 15, and 20 cm H2O applied to each subject and end-expiratory lung volume measured by respiratory inductive plethysmography.</description>
    <arm_group_label>CPAP</arm_group_label>
    <other_name>Continuous positive airway pressure, Respironics(R)</other_name>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Age between 18 and 75&#xD;
&#xD;
          -  Able to follow and understand simple instructions to collect spirometry&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Younger than 18y/o&#xD;
&#xD;
          -  Older than 75 years old&#xD;
&#xD;
          -  History of chronic obstructive pulmonary disease (COPD)&#xD;
&#xD;
          -  History of asthma&#xD;
&#xD;
          -  History of congestive heart failure&#xD;
&#xD;
          -  Measured ratio of forced expiratory volume at 1 second/forced vital capacity&#xD;
             (FEV1/FVC) &lt;70 when undergoing spirometry&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>75 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Carl B. Shanholtz, MD</last_name>
    <role>Principal Investigator</role>
    <affiliation>University of Maryland</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>University of Maryland School of Medicine</name>
      <address>
        <city>Baltimore</city>
        <state>Maryland</state>
        <zip>21201</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <verification_date>March 2022</verification_date>
  <study_first_submitted>August 9, 2012</study_first_submitted>
  <study_first_submitted_qc>August 21, 2012</study_first_submitted_qc>
  <study_first_posted type="Estimate">August 24, 2012</study_first_posted>
  <results_first_submitted>December 12, 2017</results_first_submitted>
  <results_first_submitted_qc>December 12, 2017</results_first_submitted_qc>
  <results_first_posted type="Actual">January 10, 2018</results_first_posted>
  <last_update_submitted>March 4, 2022</last_update_submitted>
  <last_update_submitted_qc>March 4, 2022</last_update_submitted_qc>
  <last_update_posted type="Actual">March 8, 2022</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>University of Maryland, Baltimore</investigator_affiliation>
    <investigator_full_name>Carl Shanholtz</investigator_full_name>
    <investigator_title>Professor of Medicine</investigator_title>
  </responsible_party>

  <clinical_results>

    <participant_flow>
      <recruitment_details>Normal subjects were recruited from the University of Maryland School of Medicine</recruitment_details>
      <pre_assignment_details>Volunteers were asked briefly about their health status and given spirometry to document no evidence of obstructive airways disease or other chronic lung disease that would impact their FRC measurements with high flow nasal cannula therapy or CPAP.</pre_assignment_details>
      <group_list>
        <group group_id="P1">
          <title>HFNC-CPAP</title>
          <description>High flow nasal cannula oxygen first period, followed by continuous positive airway pressure second period.</description>
        </group>
        <group group_id="P2">
          <title>CPAP-HFNC</title>
          <description>Continuous Positive Airway Pressure first period, followed by high flow nasal cannula second period.</description>
        </group>
      </group_list>
      <period_list>
        <period>
          <title>Period 1</title>
          <milestone_list>
            <milestone>
              <title>STARTED</title>
              <participants_list>
                <participants group_id="P1" count="4"/>
                <participants group_id="P2" count="2"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="4"/>
                <participants group_id="P2" count="2"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>NOT COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
                <participants group_id="P2" count="0"/>
              </participants_list>
            </milestone>
          </milestone_list>
        </period>
        <period>
          <title>Period 2</title>
          <milestone_list>
            <milestone>
              <title>STARTED</title>
              <participants_list>
                <participants group_id="P1" count="4"/>
                <participants group_id="P2" count="2"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="4"/>
                <participants group_id="P2" count="2"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>NOT COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
                <participants group_id="P2" count="0"/>
              </participants_list>
            </milestone>
          </milestone_list>
        </period>
      </period_list>
    </participant_flow>

    <baseline>
      <population>Normal healthy adult volunteers</population>
      <group_list>
        <group group_id="B1">
          <title>Participants</title>
          <description>Normal healthy adult volunteers</description>
        </group>
      </group_list>
      <analyzed_list>
        <analyzed>
          <units>Participants</units>
          <scope>Overall</scope>
          <count_list>
            <count group_id="B1" value="6"/>
          </count_list>
        </analyzed>
      </analyzed_list>
      <measure_list>
        <measure>
          <title>Age</title>
          <description>Age</description>
          <units>years</units>
          <param>Median</param>
          <dispersion>Inter-Quartile Range</dispersion>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="35.5" lower_limit="32.75" upper_limit="56"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Sex: Female, Male</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Female</title>
                  <measurement_list>
                    <measurement group_id="B1" value="1"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Male</title>
                  <measurement_list>
                    <measurement group_id="B1" value="5"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Race (NIH/OMB)</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>American Indian or Alaska Native</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Asian</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Native Hawaiian or Other Pacific Islander</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Black or African American</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>White</title>
                  <measurement_list>
                    <measurement group_id="B1" value="6"/>
                  </measurement_list>
                </category>
                <category>
                  <title>More than one race</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Unknown or Not Reported</title>
                  <measurement_list>
                    <measurement group_id="B1" value="0"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Region of Enrollment</title>
          <units>participants</units>
          <param>Number</param>
          <class_list>
            <class>
              <title>United States</title>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="6"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>height</title>
          <units>inches</units>
          <param>Median</param>
          <dispersion>Inter-Quartile Range</dispersion>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="71" lower_limit="68.5" upper_limit="74"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>predicted body weight</title>
          <units>kg</units>
          <param>Median</param>
          <dispersion>Inter-Quartile Range</dispersion>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="75.3" lower_limit="68.4" upper_limit="82.2"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>FEV1 (% predicted)</title>
          <units>% predicted</units>
          <param>Median</param>
          <dispersion>Inter-Quartile Range</dispersion>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="93" lower_limit="90" upper_limit="102"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>FEV1/FVC (%)</title>
          <units>ratio</units>
          <param>Median</param>
          <dispersion>Inter-Quartile Range</dispersion>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="B1" value="102" lower_limit="97" upper_limit="107"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </measure_list>
    </baseline>

    <outcome_list>
      <outcome>
        <type>Primary</type>
        <title>Change in End-expiratory Lung Volume</title>
        <description>Change in end-expiratory lung volume from baseline arbitrarily set at 0 mL.</description>
        <time_frame>baseline and after 3-5 minutes after each level of flow or pressure</time_frame>
        <group_list>
          <group group_id="O1">
            <title>HFNC</title>
            <description>High flow nasal cannula oxygen 40 liters/min</description>
          </group>
          <group group_id="O2">
            <title>CPAP</title>
            <description>Continuous positive airway pressure 20 cm H2O</description>
          </group>
        </group_list>
        <measure>
          <title>Change in End-expiratory Lung Volume</title>
          <description>Change in end-expiratory lung volume from baseline arbitrarily set at 0 mL.</description>
          <units>mL</units>
          <param>Mean</param>
          <dispersion>Standard Deviation</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="6"/>
                <count group_id="O2" value="6"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="-144" spread="317"/>
                    <measurement group_id="O2" value="103" spread="274"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
    </outcome_list>

    <reported_events>
      <time_frame>6 hours</time_frame>
      <group_list>
        <group group_id="E1">
          <title>HFNC</title>
          <description>High flow nasal cannula</description>
        </group>
        <group group_id="E2">
          <title>CPAP</title>
          <description>Continuous positive airway pressure</description>
        </group>
      </group_list>
      <serious_events>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, all-cause mortality</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="6"/>
                <counts group_id="E2" subjects_affected="0" subjects_at_risk="6"/>
              </event>
              <event>
                <sub_title>Total, serious adverse events</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="6"/>
                <counts group_id="E2" subjects_affected="0" subjects_at_risk="6"/>
              </event>
            </event_list>
          </category>
        </category_list>
      </serious_events>
      <other_events>
        <frequency_threshold>0</frequency_threshold>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, other adverse events</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="6"/>
                <counts group_id="E2" subjects_affected="0" subjects_at_risk="6"/>
              </event>
            </event_list>
          </category>
        </category_list>
      </other_events>
    </reported_events>

    <certain_agreements>
      <pi_employee>Principal Investigators are NOT employed by the organization sponsoring the study.</pi_employee>
      <restrictive_agreement>There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed. </restrictive_agreement>
    </certain_agreements>
    <point_of_contact>
      <name_or_title>Carl Shanholtz, MD</name_or_title>
      <organization>University of Maryland School of Medicine</organization>
      <phone>410.328.8141</phone>
      <email>cshanhol@som.umaryland.edu</email>
    </point_of_contact>
  </clinical_results>
</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/NCT01672242
org study id: HP-00052656
nct id: NCT01672242
lead sponsor: 
collaborator: 
has dmc: Yes
Respiratory distress is a common problem in an intensive care unit. There are multiple
      mechanisms that are used to help patients who are in respiratory distress including
      mechanical ventilation, continuous positive airway pressure (CPAP), bilevel positive airway
      pressure (BiPAP), high flow oxygen, and oxygen supplementation through nasal cannula or a
      facemask.

      The purpose of this study is to evaluate the mechanism by which Vapotherm, a high flow oxygen
      system, provides breathing support. Vapotherm provides high flow oxygen at different flow
      rates, meaning one can increase the amount of oxygen flow to help with breathing support. The
      investigators believe that this high flow oxygen system may provide similar breathing support
      that a continuous positive airway pressure machine (CPAP) machine does.
High flow nasal cannula oxygen therapy (HFNC) is a method of oxygen delivery now commonly
      used in persistently hypoxic patients refractory to conventional modes of oxygen
      supplementation (i.e. nasal cannula, facemask, non-rebreather facemask). Initially used in
      neonates, it is now increasingly popular in the adult population. While the investigators
      know how HFNC provides oxygen supplementation, the physiologic mechanism of correcting
      hypoxemia is still unclear. There are five mechanisms of hypoxemia, four which correct with
      oxygen supplementation - decreased fraction of inspired oxygen (FiO2), hyperventilation,
      ventilation-perfusion (V/Q) mismatch, and diffusion defect; and one that does not - shunt.
      The hypoxemia refractory to supplemental oxygen suggests the presence of physiologic shunt.
      The conventional non-invasive therapy to reduce shunt fraction requires raising
      end-expiratory lung volumes by raising end-expiratory airway pressures using the application
      of continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP).
      The Vapotherm® (Vapotherm®, Stevensville, Maryland) product of high flow oxygen therapy
      (Precision Flow®) is one the investigators frequently use in intensive care units at the
      University of Maryland Medical Center. It does not create a leak proof seal in the nose as
      seen in CPAP and BiPAP. Positive pressure generation has been studied in another high flow
      oxygen system called Optiflow™ (Fisher & Paykel Healthcare, Ltd., Auckland, New Zealand).
      However this device differs from Vapotherm® in that its nasal bores are large and create a
      seal in each nares thereby affected both ventilation and the level of positive end expiratory
      pressure (PEEP) generation. Additionally, these studies measured positive expiratory lung
      pressures, not volume. Positive end expiratory alveolar pressure and increase expiratory lung
      volumes in adults have not yet been demonstrated using Precision Flow®.

      HFNC is intriguing because studies and clinical data have shown it is a relatively
      non-invasive method of oxygen delivery that appears to correct hypoxemia better than other
      non-invasive methods. It is more comfortable than a CPAP machine and thus is better tolerated
      among patients, especially those who are critically ill and possibly altered. While it has
      been used in neonates for some time, its use with adults is new and needs more research.

      The investigators hypothesis is that HFNC corrects persistent hypoxemia by producing
      increased end-expiratory lung volumes thus keeping alveoli open throughout the respiratory
      cycle which other oxygen supplements are unable to do. Using healthy volunteers the
      investigators will measure end expiratory lung volumes on HFNC and compare them to those
      obtained with CPAP at graded pressures.
allocation: Randomized
intervention model: Crossover Assignment
primary purpose: Basic Science
masking: None (Open Label)
measure: Change in End-expiratory Lung Volume
time frame: baseline and after 3-5 minutes after each level of flow or pressure
description: Change in end-expiratory lung volume from baseline arbitrarily set at 0 mL.
arm group label: HFNC
arm group type: Experimental
description: High Flow Nasal Cannula (HFNC) oxygen.
arm group label: CPAP
arm group type: Experimental
description: Continuous Positive Airway Pressure (CPAP)
intervention type: Device
intervention name: HFNC
description: Graded high flow nasal cannula oxygen at 10, 20 , 30, and 40 liters per minute (LPM) to each subject and end-expiratory lung volume measured by respiratory inductive plethysmography.
arm group label: HFNC
other name: High flow nasal cannula oxygen, Precision Flow®, Vapotherm®
intervention type: Device
intervention name: CPAP
description: Graded contiuous positive airway pressure at 5, 10 , 15, and 20 cm H2O applied to each subject and end-expiratory lung volume measured by respiratory inductive plethysmography.
arm group label: CPAP
other name: Continuous positive airway pressure, Respironics(R)
criteria: 
gender: All
minimum age: 18 Years
maximum age: 75 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Carl B. Shanholtz, MD
role: Principal Investigator
affiliation: University of Maryland
facility: 
country: United States
responsible party type: Principal Investigator
investigator affiliation: University of Maryland, Baltimore
investigator full name: Carl Shanholtz
investigator title: Professor of Medicine
participant flow: 
baseline: 
outcome list: 
reported events: 
certain agreements: 
point of contact: 