简述术中发生喉痉挛和支气管痉挛的原因、表现及处理。
哪段硬膜外间隙易出现单侧阻滞现象() ["腰段","下胸段","中胸段","上胸段","颈段"]
瘕治疗方法为() ["温养肾气,调理气血","补气升提","理气散结,破血消

","通调气血","养阴润燥,佐以开郁"]
什么静脉麻醉?
硬膜外阻滞的主要机制与部位() ["椎旁阻滞","经吸收循环后再作用于脊髓","根蛛网膜绒毛阻滞脊神经根","直接透过硬膜与蛛网膜产生蛛网膜下阻滞","各种途径进入脑脊液作用于脑部"]
小儿麻醉中常见的并发症有哪些?