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Short-Duration Hypothermia Induction in Rats using Models for Studies examining Clinical Relevance and Mechanisms
Published on: March 3, 2021
Moderate superficial hypothermia prolongs bleeding time in humans
B Romlin1, K Petruson, K Nilsson
1Department of Pediatric Anaestesia and Intensive Care, The Queen Silvia Children's Hospital, Göteborg, Sweden. birgitta.romlin@vgregion.se
Acta Anaesthesiologica Scandinavica
|November 14, 2006
Summary
Mild local skin cooling significantly prolonged bleeding time in healthy volunteers, even when core body temperature remained stable. Local cooling did not affect whole blood coagulation parameters measured by thrombelastograph (TEG).
Area of Science:
- Medical Research
- Physiology
- Hemostasis
Background:
- Systemic hypothermia affects platelet function and coagulation.
- Previous research indicates systemic hypothermia influences coagulation.
- The impact of local hypothermia on bleeding time and coagulation is less understood.
Purpose of the Study:
- To test if mild local hypothermia increases bleeding time in healthy volunteers with normal core temperature.
- To assess the effect of local cooling on whole blood coagulation using thrombelastograph (TEG).
Main Methods:
- Bleeding time was measured on the forearm at baseline (32°C) and after cooling to 30°C and 28°C.
- Skin temperature was monitored continuously using thermistors.
- Whole blood coagulation was analyzed using TEG before and after cooling to 28°C.
- Core body temperature was monitored via tympanic membrane temperature.
Main Results:
- Bleeding time significantly increased at 30°C and 28°C compared to baseline.
- No significant changes were observed in any TEG parameters.
- Core body (tympanic membrane) temperature remained unchanged throughout the study.
Conclusions:
- Local skin cooling significantly prolongs bleeding time, independent of core temperature.
- Local hypothermia does not appear to influence whole blood coagulation as measured by TEG.
- Local skin temperature is a critical factor to consider when evaluating bleeding at surgical sites.
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