The risk of venous thrombosis may be increased during aeroplane flights, possibly related to the activation of coagulation by low oxygen concentration (hypoxia) that is caused by the reduction of pressure in the aircraft cabin.
Peter Robbins from the University of Oxford, UK, and colleagues exposed eight healthy human participants to eight hours of hypoxia and eight hours of normal air as a control. Venous blood was sampled before and after the exposure and analysed for markers of activated coagulation.
There were no significant changes in clotting activity between hypoxic and control environments.
Peter Robbins comments: "Although our findings exclude a major activation of the clotting system by an eight-hour exposure to hypoxia, they do not exclude more minor effects, since the number of participants was insufficient to do this analysis. In addition, our results do not exclude a major activation of the clotting system in a subset of susceptible individuals. To address these questions, a much larger scale study would be required."
Contact: Professor Peter A Robbins, University Laboratory of Physiology, University of Oxford, Parks Road, Oxford OX1 3PT; T) +44-0-1865-272490; F) +44-0-1865-272469; E) peter.robbins@physiol.ox.ac.uk
The Lancet