使用血气分析仪、pH计和pH试纸条获得的胸腔积液pH值的比较。

Comparison of pleural fluid pH values obtained using blood gas machine, pH meter, and pH indicator strip.

作者信息

Cheng D S, Rodriguez R M, Rogers J, Wagster M, Starnes D L, Light R W

机构信息

Department of Medicine, Saint Thomas Hospital and Vanderbilt University, Nashville, TN 37202, USA.

出版信息

Chest. 1998 Nov;114(5):1368-72. doi: 10.1378/chest.114.5.1368.

DOI:10.1378/chest.114.5.1368

PMID:9824016

Abstract

STUDY PURPOSE

The purpose of this study was to compare the pleural fluid pH values obtained with a blood gas machine (pHbg), with a pH meter (pHmet), and with a pH indicator strip (pHstrip), to determine if the pleural fluid pH measured by a pH meter or a pH indicator strip was sufficiently accurate for clinical decisions.

METHODS

The pleural fluid pH was determined, within 20 min after being collected anaerobically, by a blood gas machine (CIBA-Corning model 288), pH meter (Corning pH meter 610A), and pH indicator strip (Baxter Diagnostic) following routine laboratory procedures in 50 pleural fluids. Pleural fluid pH was determined in seven additional samples with the blood gas machine and a pH meter at 25 and 37 degrees C respectively, initially, and after 30 min.

RESULTS

The mean pHbg (7.42+/-0.01) was significantly less than the mean pHmet (7.58+/-0.02) or the mean pHstrip (8.23+/-0.06). There were significant differences between the pHbg and the pHmet (p < 0.001), and between the pHbg and the pHstrip (p < 0.001). Analysis of the additional seven samples demonstrated that when the blood gas machine was set at 25 degrees C, the pHbg (pHbg = 7.54+/-0.02) and the pHmet (7.53+/-0.01) were almost identical.

CONCLUSION

When the pleural fluid pH is going to be used for decision making, only the pH values provided by the blood gas machine are sufficiently accurate.

摘要

研究目的

本研究旨在比较使用血气分析仪（pHbg）、pH计（pHmet）和pH试纸条（pHstrip）测得的胸腔积液pH值，以确定用pH计或pH试纸条测得的胸腔积液pH值对于临床决策是否足够准确。

方法

按照常规实验室程序，在50份胸腔积液厌氧采集后20分钟内，分别用血气分析仪（CIBA - Corning 288型）、pH计（Corning pH计610A）和pH试纸条（Baxter Diagnostic）测定胸腔积液pH值。另外7份样本，分别在初始时、30分钟后，于25℃和37℃用血气分析仪和pH计测定胸腔积液pH值。

结果

平均pHbg（7.42±0.01）显著低于平均pHmet（7.58±0.02）或平均pHstrip（8.23±0.06）。pHbg与pHmet之间（p < 0.001）以及pHbg与pHstrip之间（p < 0.001）存在显著差异。对另外7份样本的分析表明，当血气分析仪设置在25℃时，pHbg（pHbg = 7.54±0.02）和pHmet（7.53±0.01）几乎相同。