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Updated: Jan 4, 2026

Leveraging Turbidity and Thromboelastography for Complementary Clot Characterization
Published on: June 4, 2020
The effect of normobaric hypoxic exposure on coagulation as measured by thromboelastography
Jonny Coppel1, Edward Gilbert-Kawai1, Tom Bottomley1
1University College London Centre for Altitude, Space, and Extreme Environment Medicine, University College London Hospitals National Institute for Health Research Biomedical Research Centre, Institute of Sport and Exercise Health, London, United Kingdom.
Introduction:
The physiological impact of hypoxia on coagulation has significant importance in the clinical setting, but it is not yet fully understood. Various static methods exist to investigate the process of coagulation, however, thromboelastography (TEG) provides a dynamic assessment of clot formation that can be quantitatively assessed.
Method:
Twenty-five participants were exposed to normobaric hypoxia (12.5% oxygen) for 8 h. Venous blood was taken from the participants directly pre- and post-hypoxic exposure, and coagulation was tested using TEG. Coagulation variables assessed included reaction time, split point, alpha angle, kinetics and maximum amplitude.
Results:
Time taken for clot initiation, (assessed using the split point and reaction time) was significantly reduced after 8 h of hypoxic exposure. The split point reduced from a mean of 5.20 to 4.23 min (p = 0.022), whilst the reaction time reduced from 6.09 to 4.94 min (p = 0.004). Maximum amplitude, alpha angle and kinetics did not change significantly after hypoxic exposure.
Conclusion:
The results demonstrate that subacute normobaric hypoxic exposure increases the tendency for whole blood to coagulate, as demonstrated by a reduced split and reaction time using TEG.
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