We aim to investiga the effect of hypoxia on blood coagulation and the blood cells, particularly on blood cell activation, microparticle release and expression of anionic phospholipids on the cell membrane. We also want to investigate whether the…
ID
Source
Brief title
Condition
- Coagulopathies and bleeding diatheses (excl thrombocytopenic)
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Whole blood will be used for measuring thrombin generation, platelet function
test, measuring phospholipid exposition on the cellular membranes and for a
whole blood count (Hb, Ht, number of red blood cells, number of leucocytes,
number of platelets). The whole blood thrombin generation samples will be
fixated for studying blood cell morphology using scanning electron microscopy.
Plasma will be used for measuring thrombin generation, routine coagulation
tests and for quantifying microparticles.
Secondary outcome
N.A.
Background summary
Hypoxia is an important aspect of several diseases, such as COPD and OSAS.
These diseases are also characterised by an increased risk of developing
thrombosis, for instance COPD patients admitted to the hospital have a 25%
chance of developing a pulmonary embolism. The mechanism behind this is still
unknown, but it has been suggested that immobilisation, inflammation and
hypoxia play a major role.
Recently our study group investigated the effect of hypoxia on blood
coagulation, by ascending from sea level to 4,000 m with two groups of healthy
participants: one actively climbing group and one passively ascending group
(using cable cars). By measuring thrombin generation, we found that hypoxia
leads to an elevation of thrombin generation in whole blood, but not in plasma.
Because of this discrepancy, is is thought that the cellular part of the blood
is influenced by the hypoxia and may be responsible for the increased risk of
thrombosis.
Study objective
We aim to investiga the effect of hypoxia on blood coagulation and the blood
cells, particularly on blood cell activation, microparticle release and
expression of anionic phospholipids on the cell membrane. We also want to
investigate whether the effects of a stay at high altitude (hypobaria) are
compareble to a stay in a hypoxic chamber, where air pressure is not decreased
(normobaria).
Study design
Our study consists of two parts:
Part A (Expedition): hypoxia will be induced by ascending passively from sea
level to 4,000 m, over a period of 7 days. During this expedition we will focus
on the effect of hypoxia on blood cells and blood coagulation. These data will
be correlated to our previous expedition.
Part B (Hypoxia Chamber): hypoxia will be induced by a 10 hour stay in a
normobaric hypoxic chamber, in which the oxygen level is adapted to resemble
3,000m above sea level. Healthy participats will stay twice in the room: once
exposed to room air (single blinded control), and once exposed to the hypoxia.
Intervention
N.A.
Study burden and risks
Blood samples will be drawn by venipuncture by experienced scientists.
Venipuncture can lead to a bruise.
During the Expedition a qualified medical doctor will join the group and will
monitor the health of all participants by regular measurments of vital
functions and by drawing a questionnaire about mountain sickness. Also the
group will be accompanied by an experienced qualified mountain guide who is
aquanted with the Mont Blanc area.
If a volunteer experiences any sign of mountain sickness, the volunteer will be
escorted back to the base camp at 1.000m immediately and receive immediate
care, or be brought back to The Netherlands. No unneccessary risks will be
taken.
Oxfordlaan 70
Maastricht 6229EV
NL
Oxfordlaan 70
Maastricht 6229EV
NL
Listed location countries
Age
Inclusion criteria
Healthy subjects (without any morbidity and witbout obvious signs of illness, not taking any medication interfering with coagulation), willing to participate in bot parts of our study
All healthy volunteers will undergo a physical check-up by a medical doctor. During this check-up, the medical doctor will look at the ECG, measure blood pressure, heart rate and blood oxygen level.
Subjects must be between 18 and 50 years of age. This maximum age is taken to prevent comorbodities that may influence coagulation (such as diabates, atherosclerosis, peripheral arterial disease).
Exclusion criteria
Use of medication interfering with blood coagulation (such as vitamin K antagonists, new oral anticoagulants, low molecular weight heparins).
Presence of cardiovascular disease of any other serious comorbidity.
Age below 18 of above 50 years old.
Not passing physical check-up.
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL49890.068.14 |
| Other | NTR4806 (trialregister.nl) |