The laboratory performance of the enFLOW^®, buddy lite^™ and ThermoSens^® fluid warmers

Summary We measured heating of isotonic saline by three fluid warmers in six experiments: saline at 5 C or 20 C delivered at 30, 50 or 100 ml.min^-1. At the three flow rates, the enFLOW^®, buddy lite^™ and ThermoSens^® systems heated 5 C saline to mean (SD) temperatures of: 41.1 (0.5) C, 37.7 (0.6) C and 39.1 (0.6) C; to 40.3 (0.8) C, 33.9 (1.6) C and 39.3 (0.7) C; and to 37.1 (0.8) C, 24.0 (1.3) C and 37.6 (1.0) C, respectively, p < 0.0001 for each experiment. The mean (SD) times taken to heat 5 C saline were: 16.6 (1.7) s, 258.4 (58.9) s and 134.2 (79.6) s; 16.9 (1.8) s, 256.2 (62.2) s and 182.5 (74.5) s; and 21.5 (1.5) s, 275.9 (49.3) s and 313.5 (18.0) s, respectively, p < 0.0003 for each experiment. The results for saline at 20 C were similar. The enFLOW system heated saline above 36 C faster than the ThermoSens system, whereas the buddy lite often failed to achieve 36 C.