预先吸入不同浓度富氧气体对急性低压缺氧暴露的生理影响  

Effects of preceded O_2 concentrations on physiological responses to decompression at high altitudes

作　　者：肖华军[1] 万长宏[1] 王英 陈晓勤[1] 高瑞霞[1] 贾玉兰[1] 王维山 

机构地区：[1]北京空军航空医学研究所,北京100036

出　　处：《中华航空医学杂志》1994年第3期150-156,共7页

摘　　要：通过人体急性暴露到低氧性缺氧环境和动物高空迅速减压实验，观察了预先吸入模拟分子筛产氧系统不同富氧浓度的气体对应急减压瞬间的生理影响。模拟暴发性缺氧实验结果表明，当预先供氧浓度低于60％，在暴露到暴发性缺氧环境10s内出现缺氧反应，而高于70％供氧浓度时未出现缺或变化；动物高空迅速减压缩果进一步表明，减压前预先吸入氧浓度为70％～100％，在迅速减压瞬间的生理反应是等效的，吸入各种富氧浓度气体与纯氧之间的血氧饱和度及静脉氧分压光明显差别（P＞0.05），但与迅速减压前呼吸空气（21％氧）的结果之间有显著的差别（P＜0．05）。高空迅速减压时氧自体内向外界的反向弥散有两个过程，它与减压瞬间生理效应和有效意识时间有密切关系。此结果为机教分子筛氧气系统的研制与应用提供了生理依据。To observe the effects of preceded O2 fractional concentrations on physiological responses to decompression at high altitudes,the tests simulating fulminating hypoxia at ground level in humen,and of rapid decompression at high altitudes in dogs were made. Eight young men aged 18～21 were arranged to inhale gas mixture of various O2 concentrations (50%, 60%, 70%, 80%, 90%, 100K ) for 5min separately in random order, and then inhale 0. 8% low-oxygen gas for 15 s, ECG, HbSo2 ,Po2 andPco, of expired gas were recorded following transfered to low-oxygen gas for 30 s. Eight dogs served asexperimental animals in another experiment. The preceded O2 concentrations used were 70%, 80%,90% and 100%. Decompression altitudes were 12 km, 14 km, 16 km, 18 km. Following decompressionthe breathing oxygen rich gas was turn to air for 30 s,and the physiological parameters were recorded.The group under went rapid decompression preceded with air (21% 0,) was used as control. The results of the fulminating hypoxia tests showed that in the groups preceded with 50% and 60% O2, thehypoxia responses appeared following low-oxygen exposure within 10 s, while in the groups with preceded oxygen concentration above 70%, hypoxia effects were not found. The animal experimentsdemonstrated that there was an equivalent physiological reaction following rapid decompression within 6～8 s when preceded O2 concentrations were 70% ～ 100%. In rich oxygen gas groups, oxyhemoglobinsaturation and venous Po2 had no significant difference as compared to 100% O2 group,but there wassignificant difference as compared with air (21 M O2) group (P<0. 05). The oxygen inversion diffusionfrom body to enviroment after decompression had two processes which were related with the time of effective consciousness and physiological effects. The results mentioned above provide the physiologicalbasis for design and application of molecular sieve oxygen generation system(MSOGS).

关 键 词：混合氧 肺泡氧分压 缺氧 低压 生理学 飞行人员 

分 类 号：R852.11[医药卫生—航空、航天与航海医学]