Author/Editor     Cheung, SS; Mekjavić, IB
Title     Human temperature regulation during subanesthetic levels of nitrous oxide-induced narcosis
Type     članek
Source     J Appl Physiol
Vol. and No.     Letnik 78, št. 6
Publication year     1995
Volume     str. 2301-8
Language     eng
Abstract     The present study investigated whether nitrous oxide (N2O) attenuates shivering thermogenesis during cold water immersion in a dose-dependent manner. Seven male subjects were immersed to the neck for 60 min in 20 degrees C water on five separate occasions while breathing either air (AIR) or a normoxic mixture of 10, 15, 20, or 25 percent N2O balanced with N2. All N2O concentrations investigated caused a significant (P less th. 0.02) reduction in shivering thermogenesis compared with AIR. Despite similar heat flux from the skin, the relative changes in esophageal temperature from resting preimmersion levels were significantly greater (P less th. 0.05) during the N2O trials compared with AIR, with no significant difference among the N2O conditions. A dose-dependent trend in the perception of thermal comfort was observed for the N2O conditions. It is concluded that shivering thermogenesis, and thus thermal balance, is affected to the same degree for the range of inspired N2O concentrations investigated, with no discernable dose-dependent effect.
Descriptors     BODY TEMPERATURE REGULATION
IMMERSION
NITROUS OXIDE
ADULT
ELECTROMYOGRAPHY
HYPOTHERMIA
RESPIRATION
SKIN
TIME FACTORS