氮氧和氦氧模拟饱和潜水对人体脑电图的影响

本文报道人体长时间饱和暴露于不同深度和呼吸N_2-O_2和He-O_2混合气体时的脑电图变化。结果表明,当人体暴露于相当于36.5m和50m氮氧环境的海下时,脑电图上最明显的变化是出现弥漫性的慢波,通常为每秒4—7次的θ波,个别为每秒2—3次的δ波,在50m处脑电图的变化较在36.5m处更为明显。随着在高压下停留时间的延长,脑电图的改变有一定改善:慢波减少,α波增多,这种变化和人体出现的症状有一定的关系。高压氮氧条件下导致脑电图变化的主要因素是氮的麻醉效应,另外,高压下体内二氧化碳的潴留也是脑电图变化的诱因,因为高压下重复呼吸高浓度的二氧化碳混合气可加重脑电图的改变,而用过度通气导致体内二氧化碳下降时可使异常的脑电图得到改善。在302m氦氧饱和暴露时人体脑电图的主要变化是θ活动甚至δ活动增加;α节律减少,振幅下降,在302m处还可见有θ指数的增加和α指数的减少。在上述任何压力条件下,当背景脑电图呈现以慢波为特征的异常改变时,结予光刺激可使脑电得到暂时的改善;慢波消失,α波出现,光刺激停止后,α波消失,慢波再现,这表明高压下脑电图的异常改变是脑功能的一种暂时的可逆性的变化。

THE INFLUENCE OF N_2-O-2 AND He-O_2 SATURATION DIVING ON ELECTROENCEPHALOGRAM OF HUMAN BODIESS

This paper reports the changes of the EEG of human bodies during saturation ex-posure at different depths to different mixed gases. The results of the research show thatthe most obvious on EEG was the appearance of diffused slow waves, usually θ wavesof 4- 7 times/s, and δ waves of 2- 3 times/s within individual subjects. The EEG changesat 50 m were more obvious than those at 36 .5 m. With the prolonging of time under highpressure, the EEG had some improvements, for instance, the slow waves decreased andthe α waves increased. There was a certain relationship between these changes and thesymptoms which appeared in the human body. The chief factor of the EEG changes isdue to the effect of nitrogen narcosis during the oxygen-nitrogen diving experiment. Inaddition, carbon dioxide retention under the high pressure is also a factor of the EEGchanges, because repeated inhaling of CO2-dense mixtures could aggravate the EEGchanges and the reduction of carbon dioxide in humans by hyperventilation could