Gas Exchange and Cardiovascular Kinetics of Regulation - Effects of Short Term Changes in Gravity

NCT ID: NCT02850354

Last Updated: 2016-08-01

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 18 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2015-10-31
• Study Completion Date: 2018-10-31

Brief Summary

The regulation of the cardiovascular respiratory system after changing environmental conditions or changes in work rates are essential for cognitive as well as physical functioning. For decades, it is known that high level of headward acceleration (+Gz) impairs cardiovascular function that may cause loss of consciousness. Some "anti-g" maneuvers, such as muscle contraction of the lower extremities and buttocks or intermittent exhalation on exertion (i.e., exhalation against a closed airway) have been proved to increase tolerance to high +Gz.

Main objective of this experiment is to investigate the effects of anti-g maneuvers on cardiovascular and respiratory tolerance to the push-pull-effect.

Cardiovascular and respiratory functions will be evaluated with the following parameters: heart rate, stroke volume, cardiac output, blood pressure, oxygen uptake, carbon dioxide output, ventilation, breathing frequency, body core temperature.

Electromyography (EMG) will not be a judgment criteria but will be used to check the quality of 'muscle contraction' anti-g maneuver.

The main hypothesis is that anti-g maneuvers will increase cardiovascular and respiratory tolerance to the push-pull effect, especially when they are combined.

Conditions

Healthy Volunteers

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Blinding Strategy: NONE

Study Groups

anti-g maneuvers

Before the first parabola, pulmonary function will be evaluated. Then during each weightlessness period the subject will be instructed either to stay at rest (control condition) or to perform anti-g maneuvers (4 times each): intermittent exhalation on exertion, lower limbs and abdomen muscular contraction, combined maneuver ('intermittent exhalation on exertion' + 'muscle contraction'). Before, the exhalation on exertion, the subject will close the airway after the mouthpiece by pushing on a button actuating a pneumatic valve.

Each subject will be tested during 15 parabola where the anti-g maneuvers will be performed in randomized order. After the 15th parabola, pulmonary function will be again evaluated.

Group Type: EXPERIMENTAL

anti-g maneuvers

Intervention Type: OTHER

investigate the effects of anti-g maneuvers on cardiovascular and respiratory tolerance to the push-pull-effect.

Interventions

anti-g maneuvers

investigate the effects of anti-g maneuvers on cardiovascular and respiratory tolerance to the push-pull-effect.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Healthy volunteers (men or women)
• Aged from 20 to 65
• Affiliated to a Social Security system and, for non-French resident, holding a European Health Insurance Card (EHIC)
• Who accepted to take part in the study
• Who have given their written stated consent
• Who has passed a medical examination similar to a standard aviation medical examination for private pilot aptitude (JAR FCL3 Class 2 medical examination). There will be no additional test performed for subject selection.

Subjects will be staff member of the team or of other teams participating in the parabolic flight campaign.

Exclusion Criteria

• Person who took part in a previous biomedical research protocol, of which exclusion period is not terminated
• Treated or non-treated arterial hypertension
• Smoker
• Asthma
• Respiratory bacterial or viral infection
• Pregnant women

• Minimum Eligible Age: 20 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Novespace

INDUSTRY

Sponsor Role: collaborator

University Hospital, Caen

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Pierre DP Denise, PhD

Role: PRINCIPAL_INVESTIGATOR

UMR 1075 UFR de Médecine Caen

Locations

Caen CHU

Caen, , France

Site Status: RECRUITING

Countries

France

Central Contacts

Pierre DP Denise, PhD

Role: CONTACT

pierre.denise@unicaen.fr

02.31.06.81.32 ext. +33

Cathy GC Gaillard

Role: CONTACT

gaillard-c@chu-caen.fr

02 31 06 53 49 ext. +33

Other Identifiers

2015-A01258-41

Identifier Type: -

Identifier Source: org_study_id