两种不同方法测定低水平压力支持通气时气道阻断压与自主呼吸时常规方法测定值的相关性分析

目的 拟比较以两种不同方法测定低水平压力支持通气（pressure support ventilation，PSV）病人的气道阻断压（P0．1）与自主呼吸时常规方法测定值的相关性。方法 12例机械通气病人，断开呼吸机自主呼吸时以常规方法测定P0．1得到P0．1-SB：在PSV水平为5cmH20，以常规方法和按压呼气末暂停键测定P0．1分别得到P0．1-PSV5和P0．1-PSV5eeo．分析后二者与前者之间的相关性。结果 P0．1-SB与P0．1-PSV5之间差异无显著性，P0．1-PSV5ee0分别小于P0．1-SB与P0．1-PSV5，差异有显著性；P0．1-PSV5eeo与P0．1-PSV5和P0．1-SB之间的相关系数均为0．97。结论 按压呼气末暂停键测定PSV水平为5cmH2O的P0．1值与常规方法测定的PSV水平为5cmH2O以及自主呼吸时的测定值相比，其值偏小,但前者与后二者之间具有良好的相关性。

Correlation analysis between airway occlusion pressure (P0.1) measured with two ways at low level of pressure support ventilation and that measure with conventional way at spontaneous breathing

Objective To investigate the correlation between airway occlusion pressure (P0.1) measured with two ways at low level of pressure support ventilation and that measured with conventional way at spontaneous breathing. Methods 12 patients mechanically ventilated were enrolled in the study. P0.1 was measured at spontaneous breathing with the conventional airway occlusion technique to acquired P0.1-SB, whereas at PSV level of 5cmH2O, measurement of P0.1 was performed by means of the conventional way and the end-expiratory hold function of the experimental ventilators to acquired P0.1-PSV5 and P0.1-PSV5eeo respectively. Results There was no significance between P0.1-SB and P0.1-PSV5, whereas P0.1-PSV5eeo was significantly lower than the formers. The correlation coefficients between P0.1-PSV5eeo and the formers were all 0.97. Conclusion There was good correlation between P0.1 measured with then new technique at PSV level of 5cmH2O and that measured with conventional way at PSV level of 5cmH2O as well as spontaneous breathing though the former was lower than the latter two.