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Heat transfer coefficient: Medivance Arctic Sun® Temperature Management System vs. water immersion

Published online by Cambridge University Press:  01 July 2008

M. J. English  and
T. M. Hemmerling
M. J. English*
Affiliation:
McGill University, Department of Anesthesiology, Montreal, Quebec, Canada
T. M. Hemmerling
Affiliation:
McGill University, Department of Anesthesiology, Montreal, Quebec, Canada
*
Department of Anesthesiology, D10-157.2, Montreal General Hospital, 1650 Cedar Avenue, Montreal H3G 1A4, Quebec, Canada. E-mail: [email protected]; Tel: +1 514 934 1934 Ext. 43261; Fax: +1 514 934 8249
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Summary

Background and objective

To improve heat transfer, the Medivance Arctic Sun® Temperature Management System (Medivance, Inc., Louisville, CO, USA) features an adhesive, water-conditioned, highly conductive hydrogel pad for intimate skin contact. This study measured and compared the heat transfer coefficient (h), i.e. heat transfer efficiency, of this pad (hPAD), in a heated model and in nine volunteers’ thighs; and of 10°C water (hWATER) in 33 head-out immersions by 11 volunteers.

Methods

Volunteer studies had ethical approval and written informed consent. Calibrated heat flux transducers measured heat flux (W m−2). Temperature gradient (ΔT) was measured between skin and pad or water temperatures. Temperature gradient was changed through the pad’s water temperature controller or by skin cooling on immersion.

Results

The heat transfer coefficient is the slope of W m−2/ΔT: its unit is W m−2 °C−1. Average with (95% CI) was: model, hPAD = 110.4 (107.8–113.1), R2 = 0.99, n = 45; volunteers, hPAD = 109.8 (95.5–124.1), R2 = 0.83, n = 51; and water immersion, hWATER = 107.1 (98.1–116), R2 = 0.86, n = 94.

Conclusion

The heat transfer coefficient for the pad was the same in the model and volunteers, and equivalent to hWATER. Therefore, for the same ΔT and heat transfer area, the Arctic Sun’s heat transfer rate would equal water immersion. This has important implications for body cooling/rewarming rates.

Keywords

HEAT TRANSFERHYPOTHERMIABODY TEMPERATURE REGULATION
Type
Original Article
Information
European Journal of Anaesthesiology , Volume 25 , Issue 7 , July 2008 , pp. 531 - 537
Copyright
Copyright © European Society of Anaesthesiology 2008

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References

1.English, MJM, Farmer, C, Scott, WAC. Heat loss in exposed volunteers. J Trauma 1990; 30: 422–425.CrossRefGoogle ScholarPubMed
2.Bräuer, A, English, MJM, Sander, H et al. Construction and evaluation of a manikin for perioperative heat transfer. Acta Anaesthesiol Scand 2002; 46: 43–50.CrossRefGoogle Scholar
3.Perl, T, Bräuer, A, Timmermann, A et al. Differences among forced-air warming systems with upper body blankets are small: a randomized trial for heat transfer in volunteers. Acta Anaesthesiol Scand 2003; 47: 1159–1164.Google Scholar
4.Plattner, O, Kurz, A, Sessler, DI et al. Efficacy of intraoperative cooling methods. Anesthesiology 1997; 87: 1089–1095.CrossRefGoogle ScholarPubMed
5.Layton, RP, Mints, WH, Annis, J et al. Calorimetry with heat flux transducers: comparison with a suit calorimeter. J Appl Physiol 1983; 54: 1361–1367.CrossRefGoogle ScholarPubMed
6.Frim, J, Ducharme, M. Heat flux transducer measurement error: a simplified view. J Appl Physiol 1993; 74: 2040–2044.Google Scholar
7.Sessler, D, Moayeri, A. Skin-surface warming: heat flux and central temperature. Anesthesiology 1990; 73: 214–218.CrossRefGoogle ScholarPubMed
8.Giesbrecht, G, Ducharme, M, McGuire, J. Comparison of forced-air warming systems for perioperative us. Anesthesiology 1994; 80: 671–679.Google Scholar
9.Ferretti, G, Veicsteinas, A, Rennie, DW. Conductive and convective heat flows of exercising humans in cold water. J Appl Physiol 1989; 67: 2473–2480.Google Scholar
10.Torossian, A. Survey on intra-operative temperature management in Europe. Eur J Anaesthesiol 2007; 24 (8): 668–675.Google Scholar
11.Tikuisis, P. Predicting survival time for cold exposure. Int J Biometeorol 1995; 39: 94–102.CrossRefGoogle ScholarPubMed
12.International Standard ISO 9920. Ergonomics of the thermal environment – Estimation of the thermal insulation and evaporative resistance of a clothing ensemble. Genève, Switzerlerand: International Organization for Standardization, 1995.Google Scholar
13.Bräuer, A, English, MJM, Steinmetz, N et al. Comparison of forced-air warming systems with upper body blankets using a copper manikin of the human body. Acta Anaesthesiol Scand 2002; 46: 965–972.Google Scholar
14.Tikuisis, P. Heat balance precedes stabilization of body temperatures during cold water immersion. J Appl Physiol 2003; 95: 89–96.CrossRefGoogle ScholarPubMed
15.Bullard, RW, Rapp, GM. Problems of body heat loss in water immersion. Aerospace Med 1970; 41: 1269–1277.Google Scholar
16.Witherspoon, JM, Goldman, RF, Breckenridge, JR. Heat transfer coefficients of humans in cold water. J Physiol 1971; 63: 459–462.Google ScholarPubMed
17.Rapp, GM. Convection coefficients in a forensic area of thermal physiology: heat transfer in underwater exercise. J Physiol 1971; 63: 392–396.Google Scholar
18.Nadel, ER, Holmer, I, Bergh, U et al. Energy transfers of swimming man. J Appl Physiol 1974; 36: 465–471.Google Scholar
19.Wade, CE, Dacanay, S, Smith, RM. Regional heat loss in resting man during immersion in 25.2°C water. Aviat Space Environ Med 1979; 50: 590–593.Google Scholar
20.Strong, LH, Gee, GK, Goldman, RF. Metabolic and vasomotor insulative responses occurring on immersion in cold water. J Appl Physiol 1985; 58: 964–977.Google Scholar
21.Ferretti, G, Veicsteinas, A, Rennie, D. Regional heat flows of resting and exercising men immersed in cool water. J Appl Physiol 1988; 64: 1239–1248.CrossRefGoogle ScholarPubMed
22.Tikuisis, P, Gonzalez, R, Pandolf, K. Thermoregulatory model for immersion of humans in cold water. J Appl Physiol 1988; 64: 719–727.CrossRefGoogle ScholarPubMed