呼吸机相关性肺炎与胃黏膜内pH值的关系：一项病例对照研究。

Relationship between ventilator-associated pneumonia and intramucosal gastric pHi: a case-control study.

作者信息

Hernández C, el-Ebiary M, Gonzalez J, de la Bellacasa J P, Montón C, Torres A

机构信息

Department de Medicina, Hospital Clínic, Universitat de Barcelona, Spain.

出版信息

J Crit Care. 1996 Sep;11(3):122-8. doi: 10.1016/s0883-9441(96)90008-8.

DOI:10.1016/s0883-9441(96)90008-8

PMID:8891963

Abstract

PURPOSE

Prior investigations have suggested a clear relationship between nosocomial pneumonia and intramucosal gastric pH (pHi), a probable marker of bacterial translocation.

METHODS

We studied 33 patients (18 with pneumonia and 15 without) admitted to an intensive care unit and hospitalized longer than 72 hours with the aim of assessing the relationship between nosocomial pneumonia, pHi, and outcome. pHi was estimated at the time of inclusion of patients into the study. Arterial pH (pHa) and bicarbonate and stomach pH and tonometer PtCO2 were also recorded. Values of < 7.32 or delta pHa-pHi of > +0.06 were used to differentiate between normal and low pHi. Quantitative cultures of pharyngeal swabs, gastric lumen, and protected specimen brush from lower airways were also done.

RESULTS

The mean pHi values were 7.397 +/- 0.105 (range, 7.14 to 7.53) and 7.452 +/- 0.059 (range, 7.37 to 7.56) for patients with and without pneumonia, respectively (P = .073). Five patients, all with pneumonia, had pHi < 7.32. No patients without pneumonia had pHi < 7.32 (P = .04). The mean delta pHa-pHi was 0.04 +/- 0.07 (range, -0.11 to 0.13) and 0.05 +/- 0.09 (range, -0.09 to 0.28; P = .72) for patients with and without pneumonia, respectively. However, there were significant differences when tonometer PtCO2 values of both groups were compared (38.9 +/- 8.3 and 30.6 +/- 4.7 mm Hg, respectively; P = .025). Patients with pneumonia had higher alkaline gastric lumen pH (5.2 +/- 1.0) than those without pneumonia (3.8 +/- 1.4; P = .006). Nonsurvivors (n = 7) had more acidic pHi (7.33 +/- 0.11) than survivors (7.44 +/- 0.06; P = .045). The mean gastric lumen bacterial concentration was 4.14 +/- 1.01 Log10 CFU/mL in patients with pneumonia and 4.28 +/- 1.22 Log10 CFU/mL in patients without pneumonia (P = NS). When patients with and without intramucosal gastric acidosis (pHi < 7.32) were compared, the gastric bacterial burden was 4.42 +/- 0.82 Log10CFU/mL and 4.32 +/- 1.03 Log10 CFU/mL (P = .08), respectively.

CONCLUSIONS

Most patients with nosocomial pneumonia had no associated intramucosal gastric acidosis. However, low pHi was associated with increased mortality.

摘要

目的

先前的研究表明，医院获得性肺炎与黏膜内胃pH值（pHi）之间存在明确关系，pHi可能是细菌易位的一个标志物。

方法

我们研究了33例入住重症监护病房且住院时间超过72小时的患者（18例患有肺炎，15例未患肺炎），旨在评估医院获得性肺炎、pHi与预后之间的关系。在患者纳入研究时估计pHi。还记录了动脉血pH值（pHa）、碳酸氢盐、胃pH值和张力计测量的PtCO2。pHi < 7.32或pHa - pHi差值 > +0.06用于区分正常pHi和低pHi。还对咽拭子、胃腔和下呼吸道保护性标本刷进行了定量培养。

结果

患有肺炎和未患肺炎患者的平均pHi值分别为7.397 ± 0.105（范围7.14至7.53）和7.452 ± 0.059（范围7.37至7.56）（P = 0.073）。5例患者（均患有肺炎）的pHi < 7.32。无肺炎患者中没有pHi < 7.32的情况（P = 0.04）。患有肺炎和未患肺炎患者的平均pHa - pHi差值分别为0.04 ± 0.07（范围 -0.11至0.13）和0.05 ± 0.09（范围 -0.09至0.28；P = 0.72）。然而，比较两组的张力计PtCO2值时存在显著差异（分别为38.9 ± 8.3和30.6 ± 4.7 mmHg；P = 0.025）。患有肺炎的患者胃腔碱性pH值（5.2 ± 1.0）高于未患肺炎的患者（3.8 ± 1.4；P = 0.006）。非存活者（n = 7）的pHi比存活者更偏酸性（7.33 ± 0.11比7.44 ± 0.06；P = 0.045）。患有肺炎患者的平均胃腔细菌浓度为4.14 ± 1.01 Log10 CFU/mL，未患肺炎患者为4.28 ± 1.22 Log10 CFU/mL（P = 无显著差异）。比较有和没有黏膜内胃酸缺乏（pHi < 7.32）的患者时，胃细菌负荷分别为4.42 ± 0.82 Log10CFU/mL和4.32 ± 1.03 Log10 CFU/mL（P = 0.08）。