The histamine concentration of plasma was detected before anesthesia induction and after 1?min,3?min,5?min,7?min,10?min of atracurium was injected, MAP and HR were monitored and recorded at the same time.

• 四组病人于诱导前、静注肌松药后1、3、5、7、10min抽血检测血浆组胺浓度,监测并记录相应时间点的平均动脉压(MAP)和心率(HR),并根据临床表现对病人过敏反应严重程度进行分级。