Oh T E
Department of Anaesthesia & Intensive Care, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, NT.
Ann Acad Med Singap. 1994 Jul;23(4):503-9.
Weaning from mechanical ventilation may be influenced by factors relating to equipment, techniques and procedures. Criteria to initiate weaning and predictors of weaning outcome are generally unreliable, but mechanical work of breathing, the tidal volume: frequency ratio and the inspiratory pressure: maximal inspiratory pressure ratio may anticipate those likely to fail weaning. The optimal weaning ventilatory mode is not known, but intermittent mandatory ventilation, pressure support ventilation, and continuous positive pressure ventilation are the most commonly used. The resistances of individual components of breathing circuits are extremely important. Blow-by heated humidifiers and ventilators which compensate for the impedances of their inspiratory demand valves impose clinically acceptable spontaneous breathing loads. Close monitoring, adequate respiratory muscle rest, attention to mineral deficiencies, nutrition and pulmonary hygiene are also important parts of the weaning process.
机械通气的撤机可能受到与设备、技术和操作程序相关因素的影响。启动撤机的标准和撤机结果的预测指标通常并不可靠，但呼吸机械功、潮气量与频率之比以及吸气压力与最大吸气压力之比可能有助于预测撤机失败的可能性。目前尚不清楚最佳的撤机通气模式，但间歇指令通气、压力支持通气和持续气道正压通气是最常用的。呼吸回路各个组件的阻力极为重要。旁通加热湿化器和能补偿其吸气需求阀阻抗的呼吸机所施加的自主呼吸负荷在临床上是可接受的。密切监测、给予足够的呼吸肌休息、关注矿物质缺乏、营养状况和肺部卫生也是撤机过程的重要组成部分。
