Accession Number:

ADA050547

Title:

Evidence for a Direct Role of Physical Effort in the Etiology of Heatstroke Injury and Mortality,

Descriptive Note:

Corporate Author:

ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MASS

Report Date:

1978-01-13

Pagination or Media Count:

24.0

Abstract:

A total of 171 untrained, unacclimatized and unanesthetized rates were used to evaluate the effects of sedentary and work-induced hyperthermia on the incidence of mortality and cellular injury, 24 h post-exposure. Cellular injury was defined as serum transaminase activity SGPT and SGOT exceeding 1000 IUL heatstroke levels. Both the percent mortality and the percentage of 24 h survivors with transaminase levels above 1000 IUL were plotted against maximum core temperatures. Exertion-induced hyperthermia produced a significantly higher incidence of cellular injury and heatstroke death at lower core temperatures than hyperthermia alone. With hyperthermia only, the SGPT and SGOT dose-response curves were identical. When work was combined with hyperthermia, there was a greater incidence of elevated SGOT at lower core temperatures. These curves bore a striking resemblance to curves reflecting heat andor work induced mortality in humans. The results suggest a direct role of physical effort in causing heatstroke injury and mortality. Author

Subject Categories:

  • Stress Physiology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE