title: Conductive heat exchange with a gel-coated circulating water mattress.
abstract: The use of forced-air warming is associated with costs for the disposable blankets. As an alternative method, we studied heat transfer with a reusable gel-coated circulating water mattress placed under the back in eight healthy volunteers. Heat flux was measured with six calibrated heat flux transducers. Additionally, mattress temperature, skin temperature, and core temperature were measured. Water temperature was set to 25 degrees C, 30 degrees C, 35 degrees C, and 41 degrees C. Heat transfer was calculated by multiplying heat flux by contact area. Mattress temperature, skin temperature, and heat flux were used to determine the heat exchange coefficient for conduction. Heat flux and water temperature were related by the following equation: heat flux = 10.3 x water temperature - 374 (r(2) = 0.98). The heat exchange coefficient for conduction was 121 W . m(-2) . degrees C(-1). The maximal heat transfer with the gel-coated circulating water mattress was 18.4 +/- 3.3 W. Because of the small effect on the heat balance of the body, a gel-coated circulating water mattress placed only on the back cannot replace a forced-air warming system.
authors.affiliation: *Department of Anesthesiology, Emergency and Intensive Care Medicine, Georg-August-University of Göttingen, Göttingen, Germany; †Department of Anaesthesia, Montreal General Hospital and McGill University, Montreal, Canada; and ‡Department of Anaesthesia and Intensive Care Medicine, Evangelisches Bethesda-Krankenhaus, Essen, Germany.
authors.forename: Anselm
authors.initials: A
authors.lastname: Bräuer
authors.forename: Larissa
authors.initials: L
authors.lastname: Pacholik
authors.forename: Thorsten
authors.initials: T
authors.lastname: Perl
authors.forename: Michael John Murray
authors.initials: MJM
authors.lastname: English
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Weyland
authors.forename: Ulrich
authors.initials: U
authors.lastname: Braun
mesh_terms: D000328:Adult; D000392:Air Movements; D005260:Female; D005782:Gels; D006358:Hot Temperature; D006801:Humans; D006813:Humidity; D008297:Male; D017694:Rewarming / Q000295:instrumentation*; D012881:Skin Temperature / Q000502:physiology; D013696:Temperature; D013816:Thermodynamics
chemical_list: D005782:Gels