[问答题,简答题] 麻醉前用药应依据哪些原则?

简述ASA分级标准? 椎动脉型颈椎病的典型表现是() ["A．头部转动时发作性眩晕","B．下肢无力、步伐不稳","C．颈肩臂疼痛麻木","D．心慌、胸闷","E．大小便功能障碍"] 神经根型颈椎病最常见的表现是() ["A．头痛、头晕、头部转动时发作性眩晕","B．下肢无力，步伐不稳","C．颈肩臂疼痛麻木","D．心慌、胸闷","E．大小便功能障碍"] ASA Apgar评分 麻醉前用药应依据哪些原则?