A Comparison of Rewarming Methods in Mildly Hypothermic Individuals

Abstract

The purpose of this study was to compare the rewarming effectiveness of a radio frequency coil (13.56MHz) at a specific absorption rate (SAR) of 2.5 W/kg (RF) with warm water immersion (40 C) (WW) and an insulated mummy-type rewarming sack (TS). Four male subjects, ages 24-35, were immersed in 10 C water for up to 90 minutes or until their rectal temperatures (TRE) decreased to 35 C. Each subject had 3 trials in which they were immersed. After each immersion, rewarming was accomplished with either RF, WW, or TS, so that each subject was rewarmed once with each method. Comparisons of the three rewarming methods were based on the rate of increase of TRE during rewarming (delta TRE/T), TRE 60 minutes after the start of rewarming (TRE 60), the time interval measured from extraction from the water to the end of afterdrop deltat), and the magnitude of any observed Tre afterdrop (deltaTre).WW had significantly greater deltaTRE/t and TRE60 than either RF or TS (p<0.03) and a smaller deltat than TS (p<0.05).TS had significantly greater delta TRE than either WW or RF (p<0.05). No significant differences in deltaTre/t, Tre60, or delta t were observed between TS and RF. The results of this study indicate that for mildly hypothermic individuals, rewarming with RF at a SAR of 2.5 W/kg is roughly equivalent to TS and less effective than WW.

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Document Details

Document Type
Technical Report
Publication Date
May 15, 1990
Accession Number
ADA235146

Entities

People

  • G. J. Askew
  • J. W. Kaufman
  • K. Y. Dejneka

Organizations

  • Naval Air Warfare Center Warminster

Tags

Communities of Interest

  • Advanced Electronics
  • Biomedical
  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Aircrafts
  • Body Temperature
  • Clothing
  • Death
  • Electromagnetic Radiation
  • Energy Transfer
  • Experimental Design
  • Health Services
  • Heart Rate
  • Heat Transfer
  • Hypothermia
  • Military Medicine
  • Military Research
  • Patient Care
  • Research Facilities
  • Rhesus Monkeys
  • Temperature Gradients

Readers

  • Exercise and Sports Science.

Technology Areas

  • Microelectronics