Author/Editor     Mekjavić, IB; La Prairie, A; Burke, W; Lindborg, B
Title     Respiratory drive during sudden cold water immersion
Type     članek
Source     Respir Physiol
Vol. and No.     Letnik 70, št. 1
Publication year     1987
Volume     str. 121-30
Language     eng
Abstract     Sudden decreases in cutaneous temperature induce an immediate ventilatory response, which has been termed the inspiratory or 'gasp' reflex. This respiratory response has been implicated as a contributing factor to cold water immersion drowning. In the present study, five subjects wearing either shorts or a variety of thermal protective apparel were immersed on separate occasions in 10 degrees C water. The observed peak mean skin temperature cooling rates (dTs/dt) for the different conditions varied from 6.9 +/- 2.1 degrees C/min for the shorts condition to 1.8 +/- 0.3 degrees C/min for a helicopter pilot suit made of cotton ventile material. During the immersion, recordings were made of respiratory drive, as indicated by the mouth occlusion pressure at 100 msec following the onset of inspiration (P0.1). The respiratory drive, an indicator of central inspiratory activity, correlated well with peak dTs/dt. The slope P0.1/(dTs/dt) was subject dependent and did not appear to be related to body composition. The substantial intersubject variability in the respiratory response is suggested to result from differences in the central integration of thermoafferent information. It is concluded that the inspiratory reflex is the result of cutaneous thermoreceptor activity.
Descriptors     COLD
IMMERSION
RESPIRATION
ADULT
BODY TEMPERATURE
PROTECTIVE CLOTHING
SKIN TEMPERATURE
SKINFOLD THICKNESS
THERMAL CONDUCTIVITY
TIME FACTORS