Abstract: Objective To evaluate the performance of a self-made passive blood transfusion warmer based on the coagulation exotherm of supercooled liquid,investigate the changes in blood quality after warming,and provide data support for its practical application. Methods Whole blood and suspended red blood cells stored in 2~6 ℃ was heated by passive blood transfusion warmer,and the changes of hemolysis rate,blood routine examination,biochemical indexes, morphology,membrane damage and coagulation function were detected. Results After whole blood being warmed, the white blood cells count was slightly decreased and the K⁺ concentration and MA value were slightly increased with the differences statistically significant（P<0.05）. In the case of suspended red blood cells,lactate dehydrogenase concentration were slightly increased after being warming, and the free hemoglobin concentration and hemolysis rate were slightly increased with the differences statistically significant （P<0.05）. The rest of the indicators did not show significant change. Conclusion After being warmed with the self-made warmer,although the quality-related indicators have slight changes,they are all within normal ranges. The quality of blood completely meet the requirements of GB18469-2012 "Quality requirements for whole blood and blood components".

Key words: Warming, Transfusion, Hypothermia, Quality evaluation