<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/NCT02185378</url>
  </required_header>
  <id_info>
    <org_study_id>4-2014-0302</org_study_id>
    <nct_id>NCT02185378</nct_id>
  </id_info>
  <brief_title>Effects of 1:1 Inspiratory to Expiratory Ratios on Oxygenation and Intrapulmonary Shunt Fraction During One Lung Ventilation in the Obese Patients</brief_title>
  <official_title>Effects of 1:1 Inspiratory to Expiratory Ratios on Oxygenation and Intrapulmonary Shunt Fraction During One Lung Ventilation in the Obese Patients</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Yonsei University</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Yonsei University</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      One-lung ventilation, even in patients with healthy weight, causes an impairment in&#xD;
      gas-exchange and respiratory mechanics. We hypothesized that oxygenation during the one-lung&#xD;
      ventilation in obese patients would be improved by applying inverse-ratio ventilation,&#xD;
      reducing atelectasis in the dependent lung and resulting in reduced shunt. Because of the&#xD;
      restrictive ventilatory effects of obesity, these patients often show a decreased functional&#xD;
      residual capacity and decreased expiratory reserve volume, leading to an overall decreased&#xD;
      tidal volume. These reduction leads to arterial hypoxemia, V-Q mismatch and Rt to Lt&#xD;
      shunting. There are few studies on the one lung ventilation in obese patients about this&#xD;
      prolonged inspiratory time ventilatory method. We plan to investigate the effect of this&#xD;
      ventilation method in obese patients during one lung ventilation.&#xD;
    </textblock>
  </brief_summary>
  <overall_status>Completed</overall_status>
  <start_date>July 2014</start_date>
  <completion_date type="Actual">January 2015</completion_date>
  <primary_completion_date type="Actual">January 2015</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Non-Randomized</allocation>
    <intervention_model>Parallel Assignment</intervention_model>
    <primary_purpose>Other</primary_purpose>
    <masking>Triple (Participant, Care Provider, Investigator)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Changes of the intrapulmonary shunt fraction and respiratory dynamic parameter</measure>
    <time_frame>T1 (10min before one lung ventibation) T2 (30min after one lung ventilation started)T3 (60min after one lung ventilation started) T4 (10min after two lung ventilation)</time_frame>
    <description>shunt fraction Qs/Qt = (CcO2- CaO2)/(CcO2- CvO2), CcO2 = Hgb x 1.34 x ScO2 + PcO2 x 0.003, lung compliance : Compliance= Vt / Pplat, physiologic dead space : Vd/Vt = 1.14 x (PaCO2 - PETCO2)/PaCO2- 0.005</description>
  </primary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Actual">36</enrollment>
  <condition>Obese Patients, One Lung Ventilation</condition>
  <arm_group>
    <arm_group_label>I:E ratio 1:2</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>I:E ratio 1:1</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>The purpose of our study is to compare the effects of minimal prolonged 1:1 IE ratioventilation on respiratory mechanics and oxygenation with conventional 1:2 IE ratio ventilation during OLV in obese patients.</description>
  </arm_group>
  <intervention>
    <intervention_type>Procedure</intervention_type>
    <intervention_name>I:E ratio 1:2</intervention_name>
    <description>We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.</description>
    <arm_group_label>I:E ratio 1:2</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Procedure</intervention_type>
    <intervention_name>I:E ratio 1:1</intervention_name>
    <description>The purpose of our study is to compare the effects of minimal prolonged 1:1 IE ratioventilation on respiratory mechanics and oxygenation with conventional 1:2 IE ratio ventilation during OLV in obese patients.</description>
    <arm_group_label>I:E ratio 1:1</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          1. Above 40 years of age.&#xD;
&#xD;
          2. American Society of Anesthesiologists (ASA) Physical Status I, II, III.&#xD;
&#xD;
          3. Obesity (BMI &gt;25 kg/ m2 )&#xD;
&#xD;
          4. thoracic surgical procedure&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          1. severe functional liver or kidney disease&#xD;
&#xD;
          2. diagnosed HF ( NYHA class &gt;3)&#xD;
&#xD;
          3. reduced pulmonary diffusion capacity &lt; 80%&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>40 Years</minimum_age>
    <maximum_age>80 Years</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Young Jun Oh, MD,PhD</last_name>
    <role>Principal Investigator</role>
    <affiliation>Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine</name>
      <address>
        <city>Seoul</city>
        <zip>120-752</zip>
        <country>Korea, Republic of</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>Korea, Republic of</country>
  </location_countries>
  <verification_date>March 2019</verification_date>
  <study_first_submitted>July 3, 2014</study_first_submitted>
  <study_first_submitted_qc>July 3, 2014</study_first_submitted_qc>
  <study_first_posted type="Estimate">July 9, 2014</study_first_posted>
  <last_update_submitted>March 14, 2019</last_update_submitted>
  <last_update_submitted_qc>March 14, 2019</last_update_submitted_qc>
  <last_update_posted type="Actual">March 18, 2019</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Respiratory Aspiration</mesh_term>
    <mesh_term>Obesity</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/NCT02185378
org study id: 4-2014-0302
nct id: NCT02185378
lead sponsor: 
has dmc: No
One-lung ventilation, even in patients with healthy weight, causes an impairment in
      gas-exchange and respiratory mechanics. We hypothesized that oxygenation during the one-lung
      ventilation in obese patients would be improved by applying inverse-ratio ventilation,
      reducing atelectasis in the dependent lung and resulting in reduced shunt. Because of the
      restrictive ventilatory effects of obesity, these patients often show a decreased functional
      residual capacity and decreased expiratory reserve volume, leading to an overall decreased
      tidal volume. These reduction leads to arterial hypoxemia, V-Q mismatch and Rt to Lt
      shunting. There are few studies on the one lung ventilation in obese patients about this
      prolonged inspiratory time ventilatory method. We plan to investigate the effect of this
      ventilation method in obese patients during one lung ventilation.
allocation: Non-Randomized
intervention model: Parallel Assignment
primary purpose: Other
masking: Triple (Participant, Care Provider, Investigator)
measure: Changes of the intrapulmonary shunt fraction and respiratory dynamic parameter
time frame: T1 (10min before one lung ventibation) T2 (30min after one lung ventilation started)T3 (60min after one lung ventilation started) T4 (10min after two lung ventilation)
description: shunt fraction Qs/Qt = (CcO2- CaO2)/(CcO2- CvO2), CcO2 = Hgb x 1.34 x ScO2 + PcO2 x 0.003, lung compliance : Compliance= Vt / Pplat, physiologic dead space : Vd/Vt = 1.14 x (PaCO2 - PETCO2)/PaCO2- 0.005
arm group label: I:E ratio 1:2
arm group type: Active Comparator
description: We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.
arm group label: I:E ratio 1:1
arm group type: Active Comparator
description: The purpose of our study is to compare the effects of minimal prolonged 1:1 IE ratioventilation on respiratory mechanics and oxygenation with conventional 1:2 IE ratio ventilation during OLV in obese patients.
intervention type: Procedure
intervention name: I:E ratio 1:2
description: We plan to evaluate the improvement on respiratory function with different ventilation I:E ratios (1:2 vs. 1:1) during the one-lung ventilation in an obese patients.
arm group label: I:E ratio 1:2
intervention type: Procedure
intervention name: I:E ratio 1:1
description: The purpose of our study is to compare the effects of minimal prolonged 1:1 IE ratioventilation on respiratory mechanics and oxygenation with conventional 1:2 IE ratio ventilation during OLV in obese patients.
arm group label: I:E ratio 1:1
criteria: 
gender: All
minimum age: 40 Years
maximum age: 80 Years
healthy volunteers: No
last name: Young Jun Oh, MD,PhD
role: Principal Investigator
affiliation: Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine
facility: 
country: Korea, Republic of
responsible party type: Sponsor
mesh term: Respiratory Aspiration
mesh term: Obesity