Hypothermia Induced Impairment of Platelets: Assessment With Multiplate vs. ROTEM-An In Vitro Study

Introduction: This experimental in vitro study aimed to identify and characterize hypothermia-associated coagulopathy and to compare changes in mild to severe hypothermia with the quantitative measurement of rotational thromboelastometry (ROTEM) and multiple-electrode aggregometry (MULTIPLATE).Methods: Whole blood samples from 18 healthy volunteers were analyzed at the target temperatures of 37, 32, 24, 18, and 13.7 degrees C with ROTEM (ExTEM, InTEM and FibTEM) and MULTIPLATE using the arachidonic acid 0.5 mM (ASPI), thrombin receptor-activating peptide-6 32 mu M (TRAP) and adenosine diphosphate 6.4 mu M (ADP) tests at the corresponding incubating temperatures for coagulation assessment.Results: Compared to baseline (37 degrees C) values ROTEM measurements of clotting time (CT) was prolonged by 98% (at 18 degrees C), clot formation time (CFT) was prolonged by 205% and the alpha angle dropped to 76% at 13.7 degrees C (p < 0.001). At 24.0 degrees C CT was prolonged by 56% and CFT by 53%. Maximum clot firmness was only slightly reduced by <= 2% at 13.7 degrees C. Platelet function measured by MULTIPLATE was reduced with decreasing temperature (p < 0.001): AUC at 13.7 degrees C -96% (ADP), -92% (ASPI) and -91% (TRAP).Conclusion: Hypothermia impairs coagulation by prolonging coagulation clotting time and by decreasing the velocity of clot formation in ROTEM measurements. MULTIPLATE testing confirms a linear decrease in platelet function with decreasing temperatures, but ROTEM fails to adequately detect hypothermia induced impairment of platelets.

Automated summary

Hypothermia prolongs clotting time and decreases clot formation velocity in ROTEM measurements, while also leading to a linear decrease in platelet function with decreasing temperatures.