文档介绍：第七章吸入麻醉 Inhalational Anesthesia
一、概述(introduction) (concept) (characteristic)
可控性好
不留任何后遗症
二、吸入麻醉药的吸收、分布与消除 Uptake, distribution and elimination of inhalational anesthetics
1、吸收与分布Uptake and distribution
作用部位:大脑 central nerve system
PA PB PBr 动态平衡
dynamic equilibrium
吸收与分布影响因素:
吸入浓度 inspired concentration
分钟通气量 minute volume
血/气分配系数
blood/gas partition coefficient
每分钟肺灌流量
perfusion of pulmonary
Elimination ●大部分以原形经肺排出 Eliminated mostly in an unchanged form via the lungs ●少部分经肝、肾排出 a small proportion is metabolized in liver and eliminated via kidney
三、吸入麻醉药的临床评价 Clinical evaluation of inhalational anesthetics
controllable
●与血/气分配系数有关
associated with blood/gas partition coefficient
2. 麻醉强度 anesthetic potency
●与油/气分配系数有关
associated with oil/gas partition coefficient
● MAC(minimal alveolar concentration)
MAC is minimal alveolar concentration of an inhalational anesthetic at 1 atmosphere absolute that prevents movements of 50% of the population to a standard stimulus.
3. 对心血管的影响
Effects on Cardiovascular system
●心肌抑制
depression of myocardial contractility
●增加心肌对儿茶酚胺的敏感性:氟烷
Increased myocardial excitability
Arrhythmias mon during halothane
Increased circulating catecholamines
Effects on respiratory
●呼吸抑制 Respiratory depression dose-dependent depression of ventilation ●呼吸道刺激 irritant to respiratory depression ●支气管平滑肌舒张 relaxation of bronchial smooth muscle
Effects on neuromuscular junction
●肌松作用,增强肌松剂的肌松作用
Skeletal muscle relaxation and potentiates non-depolarizing relaxants.
●安氟醚肌松作用最强
Skeletal muscle relaxation of enflurane is the greatest in all inhalational anesthetic .
●氟烷对子宫平滑肌松弛作用最强,增加产后出血可能
Hatholane relaxes uterine muscle and may cause postpartum hemorrhage.