左右肺间相互通气的高频通气机制研究

传统观念认为充足潮气量是满足呼吸的必要条件,但低气潮气量的高频通气仍能满足呼吸病患者的通气需求。为探究其通气机制,本文提出了高频通气下左右肺间存在相互通气这一观点,并开发设计了基于新鲜绵羊肺的高频通气实验平台,以测验高频通气下左右肺间的通气气流。同时,还建立了基于呼吸道对气流的黏性阻力(R)、惯性阻力(I)和肺顺应性(C)的肺通气模型,并进行通气仿真分析,进一步从理论上探讨进入左右肺内的通气气流特征。本文实验与仿真结果均表明,在一定频率的高频震荡通气条件下,进入左右肺内的气流存在相位差,因而可以引起相互通气;即使进入肺部的总气流为0,左右肺间仍存在彼此气流交换现象。本文研究证实了高频通气下左右肺间相互通气气流的存在,这一现象将有利于肺部通气更为均匀,并提高肺内氧气的利用率。

Investigating the mechanism of the high frequency ventilation for the oscillation airflow between left and right lungs

Traditionally,adequate tidal volume is considered to be a necessary condition to support respiratory patient breathing.But the high frequency ventilation(HFV)with a small tidal volume can still support the respiratory patient breathing well.In order to further explore the mechanisms of HFV,the pendelluft ventilation between left and right lungs was proposed in this paper.And a test platform by using two fresh sheep lungs was developed for investigating the pendelluft ventilation between the left and right lungs.Furthermore,considering the viscous resistance(R),inertance(I)and lung compliance(C)in the lung,a second-order lung ventilation model was designed to inspect and evaluate the pendelluft ventilation between left lung and right lungs.On referring to both results of experiments in practice and simulation in MATLAB Simulink,between the left and right lungs,the phase difference in their airflow happens during HFV at some frequencies.And the pendelluft ventilation between the left and right lungs is resulted by the phase difference,even if the total airflow entering a whole lung is 0.Under HFV,the pendelluft ventilation between left and right lungs will benefit the lungs being more adequately ventilated,and will be improve the utilization rate of oxygen in the lungs.