Efficacy of postoperative rewarming after cardiac surgery.
OBJECTIVE
To compare the efficacy of forced-air warmers and radiant heaters on rewarming after cardiac surgery in a prospective randomized study.


METHODS
Fifty male patients who had undergone coronary artery bypass graft surgery were studied. The control group (Gr. C, n=10) was nursed under a standard hospital blanket. Two groups were treated with forced-air warmers: WarmTouch 5700 (Gr. WT, n=10) and Bair Hugger 500 (Gr. BH, n=10). Two other groups were treated by radiant heaters: the Aragona Thermal Ceilings CTC X radiant heater (Gr. TC, n=10) and a self assembled radiant heater of 4 Hydrosun 500 infrared lamps (Gr. HY, n=10). Changes of oesophageal temperature, mean skin temperature, mean body temperature and relative heat balance were calculated from oesophageal temperature, 4 skin temperatures and oxygen consumption (VO(2)).


RESULTS
All actively treated groups with exception of the TC group showed significantly faster oesophageal warming than the control group. The mean body temperature increased 1.1 (0.7-1.7) degrees Ch(-1) in Gr. WT, 1.3 (0.7-1.5) degrees Ch(-1) in Gr. BH, 0.8 (0.5-1.4) degrees Ch(-1) in Gr. TC and 0.7 (0.4-1.0) degrees Ch(-1) in Gr. HY compared to Gr. C with 0.4 (0.2-0.7) degrees Ch(-1). The mean VO(2) and the maxima of the VO(2) during the study period did not differ significantly between the groups.


CONCLUSIONS
In the current setting active warming, forced-air warming more than radiant warming, increased speed of rewarming two- to threefold in comparison to insulation with a blanket.
Department of Anesthesiology, Emergency and Intensive Care Medicine, University of Götingen, Göttingen, Germany.
Anselm
A
Bräuer
Wolfgang
W
Weyland
Stephan
S
Kazmaier
Ulf
U
Trostdorf
Zoran
Z
Textor
Gerhard
G
Hellige
Ulrich
U
Braun
D000368:Aged; D001512:Bedding and Linens; D001831:Body Temperature / Q000502:physiology; D001026:Coronary Artery Bypass; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D011182:Postoperative Care / Q000295:instrumentation; D011446:Prospective Studies; D017694:Rewarming / Q000295:instrumentation*; D012768:Shivering / Q000502:physiology; D012881:Skin Temperature / Q000502:physiology; D018709:Statistics, Nonparametric; D016896:Treatment Outcome