ClinicalTrials.gov
ClinicalTrials.gov Menu
Trial record 2 of 32 for:    Recruiting, Not yet recruiting, Available Studies | "Pulmonary Atelectasis"

Atelectasis Formation: Role of Positive Pressure Breathing, Hyperoxia, and Hypobaria

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT03311347
Recruitment Status : Recruiting
First Posted : October 17, 2017
Last Update Posted : June 5, 2018
Sponsor:
Collaborators:
Uppsala University Hospital
Percy Hospital
Information provided by (Responsible Party):
Direction Centrale du Service de Santé des Armées

Brief Summary:

The primary aim of this project is to get further knowledge of the physiology of flight atelectasis and its prevention. We seek to: 1) assess whether low levels of positive pressure breathing can prevent atelectasis formation in humans during exposure to hyperoxia and +Gz-accelerations. 2) get further knowledge on the effects of hypobaria on regional ventilation and perfusion.

A secondary aim is to evaluate the effect of anti G-trouser inflation on ventilation and regional perfusion.


Condition or disease Intervention/treatment Phase
Pulmonary Atelectasis Other: +Gz accelerations and positive pressure breathing Not Applicable

Detailed Description:

The effect of positive pressure breathing on lung function is being studied, when applied during exposure to hyperoxia and +Gz-accelerations. Focus is on lung tissue compression, ventilation and regional perfusion. In addition, the influence of hypobaria on these parameters is assessed.

This study is conducted in accordance with the amended Declaration of Helsinki. The Ethics Committee Ile-de-France III (ref. 3274) and the French National Agency for Drug Safety ANSM have approved the protocol (ref. ID RCB 2015-A00485-44 and ANSM 151046B-32).

Primary aim, item 1: Experiments are conducted in a human centrifuge. The protocol mimics a routine peacetime flight in combat aircraft, and includes 1hr05 min at +1Gz followed by 10-min exposure to +1.4 to +3.5Gz . Subjects are exposed three times to this sequence, breathing at positive pressure levels of 0, 5 or 10 hPa. Two groups of sixteen healthy male non-smoking volunteers, wearing anti-G trousers, are studied and compared: group 1 breathes air, group 2 100% O2.

Primary aim, item 2: Experiments are conducted in a hypobaric chamber. Sixteen healthy male non-smoking volunteers are exposed to four conditions: 0 or 15,000 ft altitude, breathing air or 100%O2. Protocol duration is 1h15min. Positive breathing pressure can be applied depending on the results of the experiments of item 1.

Secondary aim: Experiments are conducted in a human centrifuge. Sixteen healthy male non-smoking volunteers are exposed to four conditions: uninflated or inflated anti-G trousers (175 hPa), +1 or +3.5 Gz for 3 min.


Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 80 participants
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Two arms are studied, breathing air or 100%O2. In each arm, subjects are studied at two occasions: with and without positive pressure breathing. These occasions are randomized.
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Influence of Hyperoxia and Hypobaria on Atelectasis Occurrence and Mitigation of Atelectasis Formation
Actual Study Start Date : September 14, 2015
Estimated Primary Completion Date : January 30, 2019
Estimated Study Completion Date : January 1, 2020

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Collapsed Lung

Arm Intervention/treatment
Experimental: 100%O2 breathing
Primary aim, item 1
Other: +Gz accelerations and positive pressure breathing
Experimental: Air breathing
Primary aim, item 1
Other: +Gz accelerations and positive pressure breathing



Primary Outcome Measures :
  1. atelectasis formation (change between pre and post-protocol) [ Time Frame: pre-protocol (baseline) and 1h30 min after centrifuge stop ]
    computerized tomography: 0-5 scale for size and localization

  2. change in pulmonary ventilation between 1 Gz, 1.6 Gz and 3.5 Gz [ Time Frame: pre-protocol (baseline), baseline + 1hr, baseline +1h10 min, baseline +1h15 min ]
    electrical impedance tomography: deltaZ on regions of interest

  3. change in pulmonary tissue density from baseline at centrifuge stop and 1h30 min after stop [ Time Frame: pre protocol (baseline), at centrifuge stop (baseline + 1h15 min) and 1h30 min after centrifuge stop ]
    ultrasound: number of lung comets + localization



Information from the National Library of Medicine

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, Learn About Clinical Studies.


Ages Eligible for Study:   25 Years to 45 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • normal lung function checked by pulmonary function tests.
  • normal ECG
  • normal clinical examination

Aim 1 exclusion criteria:

  • smoking
  • myopia
  • past medical history of heart or lung disease
  • current medical treatment for heart or lung disease
  • past medical history of back pain or spine trauma or disease
  • otitis
  • bad tolerance to +Gz accelerations (G-induced loss of consciousness, motion sickness)
  • claustrophobia in the centrifuge gondola

Aim 2 exclusion criteria:

  • smoking
  • past medical history of heart or lung disease
  • current medical treatment for heart or lung disease
  • otitis
  • bad tolerance to the altitude chamber (15,000 ft): ear pain, claustrophobia

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03311347


Contacts
Contact: Stephanie S Montmerle-Borgdorff, MD, PhD +33(1)78651249 stephanie.montmerle@intradef.gouv.fr
Contact: Catherine Verret, MD, PhD +33(1)78651115 catherine.verret@intradef.gouv.fr

Locations
France
Armed Forces Biomedical Research Institute Recruiting
Brétigny-sur-Orge, France, 91 223
Contact: Stephanie S Montmerle-Borgdorff, MD, PhD    +33(1)78651249    stephanie.montmerle@intradef.gouv.fr   
Contact: Maquilon-Lefebvre David, nurse    +33(1)78651091    david.maquilon@intradef.gouv.fr   
Principal Investigator: Stephanie S Montmerle-Borgdorff, MD, PhD         
Sub-Investigator: Göran Hedenstierna, Pr, MD, PhD         
Sub-Investigator: João Batista Borges, MD, PhD         
Sub-Investigator: Caroline Dussault, PhD         
Department of Radiology, Percy hospital Active, not recruiting
Clamart, France, 92140
Sponsors and Collaborators
Direction Centrale du Service de Santé des Armées
Uppsala University Hospital
Percy Hospital
Investigators
Study Chair: Dominique Felten, MD Armed Forces Biomedical Research Institute

Publications of Results:
Other Publications:
Responsible Party: Direction Centrale du Service de Santé des Armées
ClinicalTrials.gov Identifier: NCT03311347     History of Changes
Other Study ID Numbers: PDH1-SMO2-0714
First Posted: October 17, 2017    Key Record Dates
Last Update Posted: June 5, 2018
Last Verified: June 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Direction Centrale du Service de Santé des Armées:
pulmonary ultrasound
hypergravity
human physiology
oxygen
lung ventilation
lung perfusion
computed tomography
electrical impedance tomography
altitude chamber

Additional relevant MeSH terms:
Pulmonary Atelectasis
Hyperoxia
Lung Diseases
Respiratory Tract Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms