吸入纯氧对健康成人肺萎陷形成的影响

Effect of breathing pure oxygen on the development of atelectasis in healthy adults

目的观察吸入纯氧对健康成人肺萎陷形成的影响。方法健康男性志愿者6名,年龄31～36岁,体重60～80kg,身高168～179cm。分别于6个时点行室间隔平面胸部CT扫描：平静呼气末(T_1)；在残气位下吸入空气,呼气末二氧化碳分压35～45mm Hg,5min后再吸气至功能残气位(T_2)；10次深呼吸后即刻(T_3)；密闭面罩下吸入纯氧30min平静呼气末(T_4)；残气位吸入纯氧5min吸气至功能残气位(T_5)；撤掉面罩,深吸入空气10次,呼气末(T_6)。计算肺通气降低区及肺萎陷区占双肺面积的百分比。结果6名志愿者T_1时双肺均未出现通气降低区和肺萎陷区。T_2时双肺背侧通气降低区占双肺面积的(22.9±5.0)%,无肺萎陷区。T_(3、4)时双肺均无通气降低区和肺萎陷区。T_5时双肺背侧肺萎陷区占双肺面积的(4.5±1.1)%,T_6时降低至(0.9±0.4)%(P＜0.05)。结论当肺容量缩小时,吸入纯氧导致肺萎陷的形成。

Objective To investigate the development of absorption atelectasis in healthy adult volunteers breathing 100% oxygen.Methods Six healthy volunteers aged 31-36 yrs weighing 60-80 kg were recruited into this study. Chest computed tomograph （CT） of the layer of interventricular septum was performed at the end of normal expiration （FRC） at 6 time points： （1） the baseline （T1） ; （2） after 5 min maximal expiration （close to residual volume） （T2） ; （3） immediately after 10 maximal inspiration and expiration （T3 ） ; （4） after breathing 100% O2 through face mask at tidal volume for 30 min （T4） ; （5） after breathing 100% O2 at maximal expiration for 5 min （T5） and （6） breathing room air deeply 10 times （T6 ）. The area of atelectasis and poorly ventilated lung were expressed as percentage of the total lungs. Results There was no atelectasis or poorly ventilated lung at T1. At T2 the poorly ventilated lung accounted for 22.9% ± 5.0%, but there was no atelectasis. There was no atelectasis and poorly ventilated lung at T3 and T4. At T5 atelectasis accounted for 4.5 % ± 1.1% which was reduced to 0.9% ± 0.4% at T6 . Conclusion Breathing 100% oxygen at reduced lung volume can result in atelectasis.