急进高海拔时健康人夜间睡眠、呼吸状态和血氧饱和度的变化

在海拔2300m选择健康成年男性5人,急进抵海拔4660m,用多导监测仪分别在两地连续7h监测夜间睡眠、呼吸状态和血氧饱和度变化,进行自身对比。结果发现:(1)急进高海拔后,总睡眠时间、有效睡眠指数、Ⅲ～Ⅳ期深睡眠均较中度高原减少(p<0.01);总觉醒时间、Ⅰ～Ⅱ期浅睡眠高海拔较中度高原增多(p<0.05):(2)急进高海拔后,有3名健康人出现周期性呼吸,其中1名健康者出现周期性呼吸119次,伴有中枢性睡眠呼吸暂停,最低Sao_2为78％;(3)同海拔高度夜间睡眠时与清醒时Sao_2相比较,中度高原下降4.2％,高海拔下降11.2％(p<0.01);高海拔与中度高原夜间清醒时Sao_2相比较下降7.4％,睡眠时下降14.4％(p<0.001)。结果提示:(1)睡眠加重了高原人原有的低氧血症;(2)低氧血症导致睡眠结构的紊乱和睡眠质量的降低;(3)睡眠中出现的周期性呼吸,应视为机体的一种自我保护机制;(4)频发的周期性呼吸或睡眠呼吸暂停将影响大脑机能。

CHANGES OF NOCTURNAL SLEEP, RESPIRATION AND Sao_2 IN HEALTHY MEN AFTER RAPID ENTERING HIGHLAND

Nocturnal sleep, respiratory state and Sao2 in 5 healthy men were monitored for 7 hours in Xining (moderate altitude, 2 300m) and at the foot of Animaqin snow mountain (high altitude, 4 660m) respectively. Multi-channel physiological recorder was used for the assessment.The results were as foliows:(l) Total sleep time (TST), sleep efficiency index (SE1) and deep sleep stage 3 and 4 in the subjects transferred to the high altitude remarkably decreased as compared with those at moderate altitude (p< 0.001). The total waking time (TWT), non-deep sleep stage 1 and 2 were longer at high altitude than those at moderate altitute (p<0.05). (2) Periodic breathing (PB) was found in 3 of 5 subjects after entering the high altitude including the one in whom PB as qrequent as 119 with central sleep apnea and the lowest Sao2 of 78% were observed. (3) At moderate altitude, Sao2 during sleeping hours decreased by 4.2% as compared with that during waking hours at night (p< 0.001), while it fell by as much as 11.2% after having reached high altitude (p< 0.001). As compared with Sao2 at moderate altitude, the Sao2 during waking hours at night decreased by 7.4% and that during sleeping time decreased by 14.4% (p< 0.001) after entering the high altitude. These results indicated that (1) sleep aggravated the hypoxemia of highland people; (2) the periodic breathing during sleep should be considered to be a self-protective machanism; (3) hypoxemia led to the disorder of sleep components and the reduction of sleep quality; (4) the frequent periodic breathing or the sleeping apnea would affect the brain function.