人体为了维持正常的机能活动,必须不断地从外界摄取足够的氧气并从体内排出一定量的二氧化碳,才能进行正常的新陈代谢,如果气体交换发生了障碍,机体就进入一种病理状态——缺氧和二氧化碳滞留等一系列病理生理改变。所谓呼吸商(即呼吸交换率)就是在一定时问内从体内排出的二氧化碳容量与同一时间内从外界吸收的氧容量 The human body in order to maintain normal functional activity, must continue to take enough oxygen from the outside world and discharge a certain amount of carbon dioxide from the body in order to carry out normal metabolism, if gas exchange barriers, the body into a pathological state - hypoxia And carbon dioxide retention and a series of pathophysiological changes. The so-called respiratory quotient (ie, respiratory exchange rate) is the amount of carbon dioxide emissions from the body within a certain time and the same time absorbed from the outside world oxygen capacity