A.PaO2≤55mmHg或SAO2≤88%,有或沒(méi)有高碳酸血癥 B.PaO255~60mmHg,或SAO2<89%,并有肺動(dòng)脈高壓、心力衰竭、水腫或紅細(xì)胞增多癥 C.50%≤FEV1<80%預(yù)計(jì)值 D.有慢性咳嗽、咳痰癥狀 E.FEV1<50%,伴慢性呼吸衰竭