Studies on the optimal inspiratory pattern to correct the heterogeneous distribution of alveolar pressure during pressure support ventilation in septic pulmonary edema

使用最新的呼吸机，我们可以在压力支持通气（PSV）期间调节初始流量来调节吸气模式。实际上，在临床治疗中，动态测量肺泡压（PA）对于选择正确肺泡压非均匀分布的吸气方式是很困难的。我们研究了PVS过程中四种吸气方式中哪种是最优的，以均匀化狗体内PA的不均匀分布。在每个吸气模式中，10厘米水的选择压力上升时间（PRT）： 0,025,0.5，或0.75秒。我们用肺泡囊法在每个肺叶中动态地同时测量PA。在正常肺模型对照研究的基础上，我们试图通过给药白介素-1和肿瘤坏死因子来确定脓毒性肺水肿模型的最佳吸气方式。在正常肺模型中，达到所选压力支持水平越慢，初始吸气时负PA越高。在非依赖区（NDZ）和依赖区（DZ）的吸气模式中，末吸气PA均在PRT的0.5 s时最高，各PRT之间无差异。在脓毒性肺模型中，肺泡囊法测量PA非常困难，因为肺泡油分泌增加。我们清楚地表明，在正常肺非模态的PSV期间，当PRT被充分测定时，肺泡的压力传递得到改善。适当的PRT可以纠正脓毒症肺模型中PA的不均匀分布。在脓毒性肺模型的进一步研究中，有必要改进PA的测量方法。

With recent ventilators, we can regulate the initial flow rate to modulate inspiratory patters during pressure support ventilation (PSV). Actually, in clinical treatment, it is difficult to measure alveolar pressure (PA) dynamically for the selection of the inspiratory pattern that correct the heteogeneous distribution of PA.We studied which is the most optimal one among four inspiratory patterns during PVS to homogenize he heterogeneous distribution of PA in dogs. In each inspiratory pattern, 10 cm H2O of the selected pressure rising time (PRT) : 0,025,0.5, or 0.75 second. We performed simultaneous PA measurement in each of lobes dynamically with an alveoar capsule method. After the control study in normal lung models, we tried to determine the optimal inspiratory pattern in the models with septic pulmopnary edema made by administration of interleukin-1 and tumor necrosis factor.In normal lung models, the more slowly the selected pressure support level was reached, the higher was the negative PA in the initial inspiration. End inspiratory PA tended to be highest in the inspiraytory pattern with 0.5 second of he PRT in both nondependent zone (NDZ) and dependent zone (DZ), which had no difference among each PRT.In septic lung models, measurements of PA with the alveolar capsule method were very difficult by increased secretion from alveoil.We made it clear that the transmissions of pressure to alveoli were improved when the adequate determination of he PRT was done during PSV in normal lung modeless. Adequate PRT may correct the heterogeneous distribution of PA in septic lung models. It will be necessary to improve the methods to measure PA for the additional investigations about septic lung models.