[充气与放气压力-容积曲线在确定最佳呼气末正压中的比较研究]

[A comparative study between inflation and deflation pressure-volume curve in determining the optimal positive end-expiratory pressure].

作者信息

Gang Li, Sun Xiao-yi, Xu Jin-quan, Zhang Xin-li, Kou Lu-xin, Jiang Zhi-hong, Zhang Lei

机构信息

Emergency Department, Zhongshan Hospital of Dalian University, Dalian 116001, Liaoning, China. dlgangli@163. com

出版信息

Zhongguo Wei Zhong Bing Ji Jiu Yi Xue. 2012 Feb;24(2):74-7.

PMID:22316537

Abstract

OBJECTIVE

To determine the optimal positive end-expiratory pressure (PEEP) according to inflation and deflation pressure-volume curve (P-V curve) in patients with acute respiratory distress syndrome (ARDS).

METHODS

ARDS models were reproduced in 20 dogs, and they were randomly divided into two groups. In both groups, Levenberg-Marquardt iterative algorithm was employed using software to explore parameters fitting with Boltzmann formula, by which the real inflection point of pressure (Pinf d) in deflation limb or lower inflection point pressure (PLip) in inflation limb on P-V curve were defined. For the control group (inflation curve) P-V curve of PLip + 2 cm H(2)O [1 cm H(2)O = 0.098 kPa] was applied as the best PEEP value. In the experimental group (deflation curve) the Pinf d was taken as the best PEEP value. The heart rate (HR), blood pressure (BP), fingertip pulse oxygen saturation [SpO(2)], static lung compliance (Cst), arterial partial pressure of oxygen [PaO(2)] and arterial partial pressure of carbon dioxide [PaCO(2)] were monitored at 0, 2, 6, 12, 24 and 48 hours.

RESULTS

Oxygenation index increased significantly both in control and experimental groups. In experimental group, oxygenation index (mm Hg, 1 mm Hg = 0.133 kPa) of 12, 24 and 48 hours was respectively significantly higher than that of the control group (12 hours: 177.63 ± 8.94 vs. 165.60 ± 8.90, 24 hours: 194.19 ± 10.67 vs. 168.70 ± 10.60, 48 hours: 203.15 ± 13.21 vs. 171.26 ± 9.21, all P < 0.01). Cst [ml/cm H(2)O] at 2, 6, 12, 24 and 48 hours was respectively higher than that of the control group (2 hours: 41.00 ± 4.17 vs. 36.20 ± 3.90, 6 hours: 44.00 ± 4.65 vs. 36.88 ± 3.39, 12 hours: 46.92 ± 5.47 vs. 37.92 ± 3.10, 24 hours: 42.83 ± 8.97 vs. 37.92 ± 3.09, 48 hours: 42.64 ± 9.04 vs. 37.97 ± 2.98, P < 0.05 or P < 0.01).

CONCLUSION

Determining optimal PEEP for ARDS with deflation P-V curve was better than that of inflation curve.

摘要

目的

根据急性呼吸窘迫综合征（ARDS）患者的充气和放气压力-容积曲线（P-V曲线）确定最佳呼气末正压（PEEP）。

方法

在20只犬中复制ARDS模型，并将它们随机分为两组。两组均使用软件采用Levenberg-Marquardt迭代算法探索与玻尔兹曼公式拟合的参数，据此定义P-V曲线上放气支的实际压力拐点（Pinf d）或充气支的下拐点压力（PLip）。对于对照组（充气曲线），将PLip + 2 cm H₂O[1 cm H₂O = 0.098 kPa]的P-V曲线作为最佳PEEP值。在实验组（放气曲线），将Pinf d作为最佳PEEP值。在0、2、6、12、24和48小时监测心率（HR）、血压（BP）、指尖脉搏血氧饱和度[SpO₂]、静态肺顺应性（Cst）、动脉血氧分压[PaO₂]和动脉血二氧化碳分压[PaCO₂]。

结果

对照组和实验组的氧合指数均显著升高。在实验组，12、24和48小时的氧合指数（mmHg，1 mmHg = 0.133 kPa）分别显著高于对照组（12小时：177.63 ± 8.94对165.60 ± 8.90，24小时：194.19 ± 10.67对168.70 ± 10.60，48小时：203.15 ± 13.21对171.26 ± 9.21，均P < 0.01）。2、6、12、24和48小时的Cst[ml/cm H₂O]分别高于对照组（2小时：41.00 ± 4.17对36.20 ± 3.90，6小时：44.00 ± 4.65对36.88 ± 3.39，12小时：46.92 ± .47对 37.92 ± 3.10，24小时：42.83 ± 8.97对37.92 ± 3.09，48小时：42.64 ± 9.04对37.97 ± 2.98，P < 0.05或P < 0.01）。