Thermal changes observed before and after J.-L. Etienne's journey to the North Pole. Is central nervous system temperature preserved in hypothermia?
The thermoregulatory responses of a French doctor, Jean-Louis Etienne, were examined in a standard cold test before and after his journey to the North Pole, to investigate whether general and/or local cold adaptation had occurred. The two tests were carried out in a climatic chamber for 2 h at rest (dry bulb temperature, 1 degree C; relative humidity, 40%; wind speed, 0.8 m.s-1). After his journey, Etienne showed a general hypothermic-hypometabolic adaptation, i.e. a decrease in rectal temperature (Tre) and metabolic heat production (M), and an increased local skin temperature of the extremities. Between the two tests, a change occurred in the relationship between tympanic temperature (Tty) and M. During the post-journey cold test, Tty [as representative of the central nervous system (CNS) temperature] increased while the decrease in Tre was accelerated, probably due to a redistribution of blood volume towards the CNS. Such a mechanism would protect the central core with special reference to the CNS.
Bittel
J H
JH
Unité de Thermophysiologie, Centre de Recherches du Service de Santé des Armées, La Tronche, France.
Livecchi-Gonnot
G H
GH
Hanniquet
A M
AM
Poulain
C
C
Etienne
J L
JL
D000064:Acclimatization; D001110:Arctic Regions; D001831:Body Temperature; D001833:Body Temperature Regulation; D003080:Cold Temperature; D006801:Humans; D007035:Hypothermia / Q000503:physiopathology*; D007700:Kinetics; D008297:Male; D012881:Skin Temperature