Effect of Hyperoxia and Hypergravity on Lung Ventilation and Perfusion
|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. Read our disclaimer for details.|
|ClinicalTrials.gov Identifier: NCT01993394|
Recruitment Status : Completed
First Posted : November 25, 2013
Last Update Posted : November 25, 2013
|Condition or disease||Intervention/treatment||Phase|
|Atelectasis||Other: hypergravity Other: gas mixture||Not Applicable|
Experiments were conducted in a human centrifuge. The protocol aimed at mimicking a routine peacetime flight in combat aircraft, and included 10-min exposure to +1.4 - +3.5 Gz. Subjects were exposed three times to this sequence, breathing air, 44.5% O2 or 100% O2.
Ten volunteers wearing anti-G trousers participated in the study. The Ethics Committee Ile-de-France III and the French National Agency for Drug Safety (ANSM) approved the protocol (number 2009-A01092-55).
Three different imaging techniques, electrical impedance tomography (EIT), pulmonary ultrasound and chest SPECT/CT were used and compared. EIT enabled ventilation monitoring in the human centrifuge, whereas pulmonary ultrasound and SPECT/CT gave functional and topographical information before and after exposure to +Gz accelerations. EIT analysis focused on regional ventilation, SPECT on global lung ventilation and perfusion, CT on the presence of atelectasis, and pulmonary ultrasound analysis looked for comet tails in 64 chest areas. Arterial blood pressure was recorded continuously by finger photoplethysmography. Cardiac output and stroke volume were computed from these recordings, using three different algorithms. Echocardiography was used as reference non-invasive technique for stroke volume determination and performed before and after exposure to +Gz accelerations.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||20 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||Single (Outcomes Assessor)|
|Primary Purpose:||Basic Science|
|Official Title:||Influence of Hyperoxia and Hypergravity on Pulmonary Ventilation and Perfusion|
|Study Start Date :||October 2011|
|Actual Primary Completion Date :||July 2012|
|Actual Study Completion Date :||July 2012|
hypergravity gas mixture
1hr sitting rest followed by 10 min of hypergravity (2 centrifuge runs)
Other: gas mixture
breathing air, 44.5%O2 or 100%O2
- change in regional ventilation distribution [ Time Frame: baseline, 2hrs 30min ]"per lobe and per quadrant at 5th intercostal space level"
- change in regional pulmonary perfusion [ Time Frame: baseline, 2hrs 30min ]"per lobe and per quadrant at 5th intercostal space level"
- cardiac output (L/min) [ Time Frame: 2hrs ]"echocardiography (sub-aortic diameter), photoplethysmography (Liljestrand, systolic area and Windkessel algorithms)"
- tidal volume [ Time Frame: 2hrs 30min ]global (mL, area under the flow versus time curve) and regional (% change per quadrant at 5th intercostal space level)
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): NCT01993394
|Armed Forces Biomedical Research Institute|
|Brétigny-sur-Orge, France, 91 223|
|Department of Nuclear Medicine, Val-de-Grâce hospital|
|Paris, France, 75005|
|Study Chair:||Daniel Garin, MD, PhD||Armed Forces Biomedical Research Institute|