第六届现代麻醉与监测新进展高级讲习班资料.pdf

1. ······································· 2. ·········································· 3. ·········································· 4. ·························· 5. ······························· 6. ·································· 7. ·········································· 8. ······························· 9. ·································· 10. ·················· 11. ········································ 12. Anaesthesia and Muscle Relaxants in Myasthenia Gravis ····································································· 13. ···························· 14. ································ 心脏病人围术期管理的若干问题 北京阜外心血管病医院 李立环 一、麻醉前准备和麻醉前用药 （一）冠心病 理想的术前准备及麻醉前用药应使病人入手术室呈嗜睡状，无焦虑、紧 张，表情淡漠，对周围漠不关心。心率慢于 70/min，血压较在病房时低 5%～ 10%，无胸痛、胸闷等任何心血管方面的症状。为达到上述要求，麻醉前用药除 投以适量的镇静或安定药外，应参考术前心率、血压的变化情况及与心绞痛之 间的关系，投入适量的β—阻滞药和（或）钙通道阻滞药。一般情况下，劳力 性心绞痛应以β—阻滞药为主，不稳定性心绞痛应给予钙通道阻滞药。术前心 率偏快者（70/min），应加大β阻滞药的药量。血压偏高者，可考虑增加钙通 道阻滞药的用量。心绞痛多在凌晨发作的，亦应给以钙通道阻滞药。 心绞痛发作时伴随的循环动力学变化亦应作为术前用药的参考。心绞痛发 作时伴心率增快者，应加大β阻滞药的用量；如血压升高，可增加钙通道阻滞 药的用量。如病人心功能良好，可投予较大剂量的β阻滞药和钙通道阻滞药。 不同的手术模式也应作为术前用药的参考，即在心肺转流（CPB）下完成手 术还是不用心肺转流（off-pump）？如在 off-pump 下手术，为便于术中控制心 率，可考虑加大β阻滞药的用量。 一般情况下，冠心病人对上述术前用药有较大的耐受性，尤其是左主干或 3 支病变、术前无心肌梗死病史者。该类病人接受较大剂量的β阻滞药和钙通道 阻滞药非常有利于安全渡过术晨和麻醉诱导前心肌缺血易发期。但对术前心功 能较差者，尤其是高度依赖交感神经张力维持心排血量者，β阻滞药和钙通道 阻滞药可促发严重的心力衰竭。因此，对心脏扩大、合并室壁瘤、左室射血分 数（LVEF）低下、不能耐受心率减慢的病人，应谨慎使用β—阻滞药和钙通道 阻滞药。 （二）瓣膜性心脏病 除单一的主动脉瓣损害者外，需行瓣膜置换的心脏病人术前往往有心房纤 颤。严重的二尖瓣或主动脉瓣狭窄的病人，术前必须控制心室率。在充分洋地 黄准备