急性缺氧对膈肌疲劳的影响

Effect of acute hypoxemia on diaphragmatic fatigue

本文观察急性缺氧对犬膈肌疲劳的影响，发现急性缺氧条件下，膈肌疲劳的耐受时间为１８．００±３．７０ｍｉｎ，较对照组４１．３３±５．３０ｍｉｎ明显缩短（Ｐ＜０．０５），而且疲劳膈肌恢复过程中产生跨膈压（ｔｒａｎｓｄｉａｐｈｒａｇｍａｔｉｃｐｒｅｓｓｕｒｅ，Ｐｄｉ）明显低于对照组（Ｐ＜０．０５），证实急性缺氧使膈肌疲劳的耐受性明显下降，且不利于疲劳膈肌肌力的恢复。

Ten dogs were randomly divided into two groups in order to observe theeffect of acute hypoxemia on canine diaphragmatic fatigue. In hypoxemia group(n=5),diaphragmatic fatigue was produced during hypoxemia while the control group(n=5)was breathing room air.It was found that:1) hypoxemia group had much shorterendurance time than control group;2 )at 60, 120 min after fatigue,the transdiaphrag-matic pressure(Pdi)at all frequency of stimulation in hypoxemia group was less thanthat in control group.It is concluded that acute hypoxemia not only increased the dia-phragmatic fatigue but also delayed the recovery of diaphragmatic fatigue.