呼气末二氧化碳监测在血流动力学监测中的应用

Application of end-tidal carbon dioxide monitoring in hemodynamic management

呼气末二氧化碳(end-tidal CO2,ETCO2)是指呼气终末期呼出的混合肺泡气体内二氧化碳的分压或浓度。ETCO2既反映肺血流量,又可以反映心排血量(cardiac output,CO),并能间接体现冠状动脉的灌注情况,与每分通气量成负相关,与CO和二氧化碳产生量(VCO2)成正相关[1-2]。近年来,监测机械通气患者及自主呼吸患者的ETCO2已成为患者管理的重要组成部分。监测ETCO2除了评估通气外,还可以提供有关肺部通气-血流比、CO和代谢率等重要的生理数据信息。

End-tidal CO2(ETCO2) refers to the partial pressure or concentration of carbon dioxide in the mixed alveolar gas exhaled at the end of expiration. ETCO2 is determined by minute ventilation, lung blood flow and carbon dioxide(VCO2) produced by cell metabolism. Therefore, ETCO2 can comprehensively evaluate the three main functions of the human body: metabolism, blood circulation and alveolar ventilation. With the increasing maturity of ETCO2 monitoring technology, it has been widely used in clinical practice. At present, ETCO2 monitoring is mainly used in clinical applications: airway positioning, respiratory monitoring, circulation monitoring, auxiliary diagnosis and disease evaluation. This article mainly discusses the application of ETCO2 in hemodynamic monitoring, including monitoring of spontaneous circulation recovery in cardiopulmonary resuscitation, resuscitation evaluation and volume response evaluation.