Now Available for Public Comment: Notice of Proposed Rulemaking (NPRM) for FDAAA 801 and NIH Draft Reporting Policy for NIH-Funded Trials

Cardiac Autonomic Functions During Head-out Immersion and During Head Down Tilt (IMMERSION)

This study has been completed.
Sponsor:
Collaborator:
Ministry of Health, France
Information provided by:
Centre Hospitalier Universitaire de Saint Etienne
ClinicalTrials.gov Identifier:
NCT00515645
First received: August 13, 2007
Last updated: July 18, 2011
Last verified: July 2011

August 13, 2007
July 18, 2011
April 2008
July 2011   (final data collection date for primary outcome measure)
heart rate variability [ Time Frame: inclusion, one week, two weeks ] [ Designated as safety issue: No ]
heart rate variability [ Time Frame: inclusion, one week, two weeks ]
Complete list of historical versions of study NCT00515645 on ClinicalTrials.gov Archive Site
  • Blood pressure variability [ Time Frame: inclusion, one week, two weeks ] [ Designated as safety issue: No ]
  • Spontaneous baroreflex activity [ Time Frame: inclusion, one week, two weeks ] [ Designated as safety issue: No ]
  • Pulmonary diffusion [ Time Frame: inclusion, one week, two weeks ] [ Designated as safety issue: No ]
  • Upper limbs vascular resistance [ Time Frame: inclusion, one week, two weeks ] [ Designated as safety issue: No ]
  • post ischemic forearm hyperemia [ Time Frame: inclusion, one week, two weeks ] [ Designated as safety issue: No ]
  • Hematocrit rate [ Time Frame: Inclusion, one week, two weeks ] [ Designated as safety issue: No ]
  • Cardiac haemodynamic [ Time Frame: Inclusion, one week, two weeks ] [ Designated as safety issue: No ]
  • Blood pressure variability [ Time Frame: inclusion, one week, two weeks ]
  • Spontaneous baroreflex activity [ Time Frame: inclusion, one week, two weeks ]
  • Pulmonary diffusion [ Time Frame: inclusion, one week, two weeks ]
  • Upper limbs vascular resistance [ Time Frame: inclusion, one week, two weeks ]
  • post ischemic forearm hyperemia [ Time Frame: inclusion, one week, two weeks ]
  • Hematocrit rate [ Time Frame: Inclusion, one week, two weeks ]
  • Cardiac haemodynamic [ Time Frame: Inclusion, one week, two weeks ]
Not Provided
Not Provided
 
Cardiac Autonomic Functions During Head-out Immersion and During Head Down Tilt
Cardiac Autonomic Functions During Head-out Immersion and During Head Down Tilt

Head down tilt (HDT) was widely used to simulate microgravity effects on cardiovascular system. HDT could be a suitable model of water immersion (WI) which is also used to simulate the cardiovascular effects of microgravity and which is not easy to study in laboratory. To define the possibility to simulate immersion by HDT, a comparison between these models is required. A comparison between WI and few angles during HDT seems necessary to understand which angle is more adapt.

The immersion induces an increase of the central blood volume. This increase is caused by a redistribution of blood from peripheral portions of the body to the intrathoracic circulation. It seems to load cardiopulmonary and arterial baroreceptors. These baroreceptors bring into play autonomic nervous system (ANS) activation and induce a bradycardia.

HDT induces an increase in central blood volume as supported by the central venous pressure and cardiac volume increase and in return, MSNA and heart rate decrease. These cardiovascular effects seem to be the same as the thermoneutral immersion and suggest that the ANS activation is the same during HDT and WI.

Nevertheless, a few previous studies about ANS in HDT indicate some discordant results: a sympathetic decrease was reported but several results show an increase of parasympathetic activity linked with a trend of increase of arterial baroreflex. The aim of this study is to assess ANS activity in HDT on different angles (-6° and -15°) and WI. The investigators suppose an increase of parasympathetic activity during WI corresponding to parasympathetic activation during HDT especially at -6°.

Not Provided
Interventional
Not Provided
Allocation: Non-Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Basic Science
Healthy
Other: Head-down tilt and immersion
Head-down tilt -6° at inclusion, head-down tilt -15° at week one and Water Immersion at week two
Experimental: 1
Intervention: Other: Head-down tilt and immersion

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
15
July 2011
July 2011   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Sportsman
  • None coffee, alcohol, cigarettes 6 hours before the start of each visit
  • Each meal must have been taken 4 hours before each visit
  • No intensive sport 48 hours before ech visit
  • Written inform consent

Exclusion Criteria:

  • Subject with cardiovascular,renal disease or with metabolic syndrome
  • Subject with medication
  • Subject who participated to an other medical research
Male
18 Years to 40 Years
Yes
Contact information is only displayed when the study is recruiting subjects
France
 
NCT00515645
0708061, 2007-A00727-46
No
Clément CAILLAUX, Centre Hospitalier Universitaire de Saint Etienne
Centre Hospitalier Universitaire de Saint Etienne
Ministry of Health, France
Principal Investigator: Frédéric Roche, MD PhD Centre Hospitalier de Saint-Etienne
Centre Hospitalier Universitaire de Saint Etienne
July 2011

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP