Literature is also summarized regarding the need to exhale to FRC or RV before inhaling from MDI plus valved holding chambers or other extension devices and from dry powder inhalers.

• 关于使用MDI和单向储雾器或其它辅助吸入治疗器以及干粉吸入器前需要呼气至FRC或RV，我们也对文献做了总结。