气管内肺通气对急性肺损伤羊通气功能的影响

气管内肺通气（ＩＴＰＶ）是一种新的持续正压通气方式。本研究应用直流和反流两种气管插管内导管进行ＩＴＰＶ，并与压力控制通气（ＰＣＶ）进行比较。结果显示：直流ＩＴＰＶ的ＰａＣＯ２下降０．６９～０．９３ｋＰａ（１ｋＰａ＝７．５ｍｍＨｇ，Ｐ＜０．０５），生理死腔（ＶＤ）减少０．８ｍｌ／ｋｇ；反流ＩＴＰＶ的ＰａＣＯ２下降１．０７～１．３３ｋＰａ（Ｐ＜０．０１），ＶＤ减少１．０ｍｌ／ｋｇ；在维持ＰａＣＯ２５．０７±０．４４ｋＰａ条件下，反流ＩＴＰＶ气管内吸气压峰压（ＰＩＰ）下降３３％，平均气道压（Ｐａｗ）下降约５０％；ＰａＯ２和血流动力学参数均无显著变化（Ｐ＞０．０５）。提示：ＩＴＰＶ通过减少生理死腔使通气效率提高，可以用较低的ＰＩＰ和Ｐａｗ维持肺的正常气体交换；反流ＩＴＰＶ比直流ＩＴＰＶ显示更有效的通气效率

Effects of intratracheal pulmonary ventilation on ventilatory efficiency in sheep with acute lung injury

idal ventilation with continuous gas flow through a catheter at the carina reduces dead space and increases ventilatory efficiency.This study compared the intratracheal pulmnonary ventilation(ITPV) using two types of intratracheal catheter with pressure control ventilation (PCV) in adult sheep before and after lung injury.The result showed that ITPV significantly decreased PaCO 2V D( P <0 01) and markedly increased CO 2 ( P <0 01).ITPV with reverse flow catheter was more effective than ITPV with straight tipped catheter in reducing V D,especially in lung injury.It is suggested that ITPV increases ventilatory efficiency by reducing physiologic dead space,and maintains CO 2 exchange and oxygenation at lower PIP P aw and V T.ITPV with reverse flow.