慢性呼吸衰竭患者机械通气的指征，错误的是() ["A．PaCO2进行性升高","B．PaCO2升高达到80mmHg以上","C．严重的低氧血症，积极氧疗后，PaO仍为40mmHg","D．呼吸频率超过35次/分","E．并发肺性脑病"]
呼吸衰竭时，呼吸器使用不当可发生哪些危害() ["A．加重二氧化碳潴留","B．呼吸性碱中毒","C．加重心力衰竭","D．气胸","E．以上全都是"]
吸痰法
呼吸衰竭时，临床上最早出现的症状是() ["A．发绀","B．消化道出血","C．呼吸困难","D．血尿","E．心悸"]
丝脉
平均动脉压
