Comparison of forced-air warming and resistive heating.
BACKGROUND
Perioperative hypothermia is common during anesthesia and surgery and is accompanied by several complications. Forced-air warming is recognized as an effective procedure to prevent hypothermia. The aim of this study was to compare a resistive heating device with a forced-air warming device.


METHODS
Prospective randomized trial.


METHODS
heat transfer laboratory of a University hospital.


METHODS
six healthy volunteers.


METHODS
warming with a forced-air warming device (BairHugger 505 and Upper Body Blanket 522; Arizant Healthcare Inc., Eden Prairie, MN, USA) or a resistive heating device (Geratherm Adult system; Geratherm Medical AG, Geschwenda, Germany).


METHODS
heat transfer was measured with 11 calibrated heat flux transducers on the upper body. Additionally, blanket and skin temperatures were measured. The t-test for matched pairs was used for statistical evaluation.


RESULTS
Skin temperature under the covered surface was not statistically different between the two groups (37.3+/-0.2 degrees C in the forced-air warming group and 37.8+/-0.2 degrees C in the resistive heating group). In contrast, blanket temperature (40.3+/-0.6 degrees C vs 38.1+/-0.4 degrees C, P=0.002) and heat transfer (13.2+/-3.6 W vs 7.8+/-1.9 W, P=0.048) were significantly higher in the resistive heating group.


CONCLUSIONS
Heat transfer in the resistive heating system was significantly greater than that of the forced-air warming system.
Perl
T
T
Department of Anesthesiology, Emergency and Intensive Care Medicine, University of Goettingen, Goettingen, Germany.
Flöther
L
L
Weyland
W
W
Quintel
M
M
Bräuer
A
A
D000328:Adult; D000388:Air; D006361:Heating / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007035:Hypothermia / Q000517:prevention & control*; D007431:Intraoperative Complications / Q000517:prevention & control*; D008297:Male; D011183:Postoperative Complications / Q000517:prevention & control*; D011446:Prospective Studies