The patients were preoxygenated for min using a close-fitting face mask and 00% O at l0L·min- . Inhalation of nitrous oxide was then started.
The patients were preoxygenated for min using a close-fitting face mask and 00% O at l0L·min- . Inhalation of nitrous oxide was then started.
用面罩吸氧去氮,min后吸入氧气与氧化亚氮的混合气体,总流量为0L·min-。