吸氧排氮对家兔氮排出量及减压气泡形成的影响【论文】

吸氧排氮对家兔氮排出量及减压气泡形成的影响【论文】 吸氧排氮对家兔氮排出量及减压气泡形成的影响 吸氧排氮对家兔氮排出量及减压气泡形成的影响 作者: 吴燕红,孙喜庆,王永春,张舒,倪鹤鹦,全海曦 【关键词】 吸氧排氮 Nitrogen output and bubbles formation during depression after denitrogenation in rabbits 【Abstrat】 AIM: To analse quantitativel the effiien of nitrogen elimination at different denitrogenation time. METHODS: Tentfour rabbits ere randoml pided into ontrol group, denitrogenation 30, 60 and 120 min groups. The rabbits ere anesthetized and ventilated b mehanial ventilator. After 0, 30, 60 and 120 min of denitrogenation, the rabbits ere exposed to 11000 m for 30 min. The nitrogen output as analsed b hromatograph and the gas bubbles generated in the bod of rabbits ere monitored b Doppler ultrasound method. RESULTS: The nitrogen onentration and nitrogen output dereased sharpl in the first 5 min of denitrogenation, then dereased graduall ith the prolonged denitrogenation time. Aumulative number of bubbles dereased ith the elapse of denitrogenation time. Aumulative number of bubbles as negativel orrelated ith denitrogenation time . As pared ith the ontrol group, aumulative number of bubbles dereased signifiantl in denitrogenation 60 and 120 min groups. CONCLUSION: The nitrogen output dereases sharpl at first and then graduall. Denitrogenation for 60 and 120 min ma redue gas babbles during de pression in rabbits. 【Keords】 denitrogenation; nitrogen output; depression; gas bubble formation; rabbits 【摘要】 目的: 定量分析不同吸氧排氮时家兔的吸氧排氮效率，为制定我国航天员出舱活动吸氧排氮方案提供理论依据. 方法: 24只家兔随机分为对照组、吸氧排氮30, 60和120 min组4组. 麻醉后行机械通气，分别吸氧排氮0, 30, 60和120 min，收集呼出气,定量分析不同吸氧排氮时间的氮排出量，并用超声多普勒低压舱上升至11 000米停留30 min的气泡产生情况. 结果: 在吸氧排氮的前5 min，呼出气氮体积分数和氮排出量降低幅度最大(约93%)，之后随着吸氧排氮时间的延长逐渐缓慢降低;累积气泡数随着吸氧排氮时间的延长而减少，吸氧排氮60和120 min组家兔累积气泡数较对照组显著减少(P 0.0 1) ，累积气泡数与吸氧排氮时间呈负相关(r,-0.63, P 0.0 1) . 结论: 吸氧排氮过程的特点为先快后慢，吸氧排氮60和120 min可显著减少高空减压时气泡的产生. 【关键词】 吸氧排氮;氮排出量;减压;气泡形成;兔 0引言 当前航天减压病已经成为威胁航天员生命安全的潜在危险因子,1,，除提高飞行器座舱和航天服的压力外，低压暴露前预先在地面吸氧以增加排氮量是目前有效的预防措施,2,，并为各航天大国所采用. 但世界各国采用的吸氧排氮方法各异，吸氧排氮时间也不完全统一,3,.