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Updated: Jan 16, 2026

An In Vitro Hemodynamic Loop Model to Investigate the Hemocytocompatibility and Host Cell Activation of Vascular Medical Devices
Published on: August 21, 2020
10° compared to 22° celsius cold fluid bolus does not affect hemostasis in healthy adults - A randomized crossover
Casper Nielsen1, Ane Johanne Davidsen Dahlberg1, Mikkel Brabrand2
1Department of Emergency Medicine, Odense University Hospital, J. B. Winsløws Vej 4, 5000, Odense, Denmark.
Aims:
Previous studies suggest that infusing cold crystalloid fluid may have beneficial hemodynamic effects. This raises questions about the optimal temperature for fluid administration in the management of hypotensive patients, particularly regarding its impact on hemostasis and safety in patients at risk of bleeding. This study examined the effects of administering a 1000 mL bolus of Ringer's lactate at a temperature of 10 °C or 22 °C on hemostasis.
Methods:
Twenty-five healthy participants were randomized to receive Ringer's lactate at either 10 °C or 22 °C, followed by cross-over to the alternative temperature. The primary outcome was change in clotting time. Secondary outcomes included alterations in thromboelastometry amplitude after 5 and 10 min, maximum clot firmness and maximum lysis at baseline and after 30 min. Additional secondary outcomes were differences in activated partial thromboplastin time (aPTT), international normalized ratio (INR), platelet count, platelet pre-activation and fibrinogen.
Results:
ROTEM® analysis demonstrated a prolonged clotting time (mean difference: 2.6 s, 95 % CI: 0.30 to 4.90) after 30 min among participants who received a 10 °C bolus. No other alterations were observed in thromboelastometry. Additionally, fibrinogen levels were slightly elevated after 30 min.
Conclusion:
Administration of a bolus of Ringer's lactate at 10 °C compared to 22 °C resulted in a minor prolongation of clotting time after 30 min as assessed by thromboelastometry and had minimal impact on hemostasis. Fibrinogen was slightly elevated after 30 min. We conclude that administering 1000 mL of cold fluids does not notably affect hemostasis and is considered safe in healthy adults.

