Effect of rewarming and homeostasis of groin-mediated forced-air warming system in patients with hypothermia after cardiopulmonary bypass

Objective To investigate the rewarming effect of groin-mediated forced-air warming system in patients with hypothermia after cardiopulmonary bypass. Methods A total of 100 hypothermia patients after cardiopulmonary bypass were divided into observation group and control group with 50 cases each by random digits table method. Patients in control group received pelma-mediated forced-air warming system, observation group carried out groin-mediated forced-air warming system. The levels of bladder temperature, axillary temperature and lactate concentration were monitored at 10 min (T10), 30 min (T30), 60 min (T60), 90 min (T90) after rewarming in two groups, rewarming time and drainage volume at 90 min after rewarming between two groups was also compared. Results Bladder temperature in observation group were (34.44±0.98), (35.44±1.12), (36.71±1.16), (37.60±1.45) ℃ at T10, T30, T60, T90, axillary temperature were (34.30±1.85), (35.31±1.36), (36.38±1.57), (37.28±1.72) ℃, bladder temperature and axillary temperature in control group were (34.18±1.56), (36.91±1.61), (37.70±1.29), (37.40±1.10) ℃ and (34.45±1.03), (36.30±1.25), (37.70±1.23), (37.19±1.31) ℃, respectively. There was no significant difference in bladder temperature and axillary temperature at T10 and T90 (P>0.05), however, the bladder temperature and axillary temperature was significantly decreased in observation group compared to control group at T30 and T60 (t value was 5.309, 4.073, P 0.05), however, the lactate concentration was significantly decreased in observation group compared to control group at T60 and T90 (t value was 7.276, 8.640, P<0.01), in addition, there were crossover effect of time and grouping factor in lactate concentration (F value was 36.034, P<0.01). Drainage volume at 90 min after rewarming were (95.44±15.24) ml in observation group, (106.08±25.56) ml in control group, the difference was significant between two groups (t value was 2.528, P<0.05). Conclusions Groin-mediated forced-air warming system can effectively and uniformly rewarming the body temperature of patients with hypothermia after cardiopulmonary bypass and served as a potential rewarming strategy. Key words: Cardiopulmonary bypass; Forced-air rewarming; Bladder temperature; Axillary temperature