Elsevier

Respiratory Medicine

Volume 104, Issue 6, June 2010, Pages 822-828
Respiratory Medicine

Mechanical ventilation induces changes in exhaled breath condensate of patients without lung injury

https://doi.org/10.1016/j.rmed.2010.01.013Get rights and content
Under an Elsevier user license
open archive

Summary

Introduction

Measurement of biomarkers in exhaled breath condensate (EBC) may be useful for monitoring lung inflammation and injury in mechanically ventilated patients. The aim of this study was to analyze changes in biomarkers of inflammation in EBC associated with prolonged mechanical ventilation.

Methods

EBC samples were collected from critically ill patients weaning from mechanical ventilation without lung disease and from healthy nonsmokers. The following parameters were measured: pH after helium deaeration, nitrogen oxide and 8-isoprostane concentrations.

Results

EBC was obtained from 10 patients and 20 controls. Ventilation time before the start of sample collection was 250 (85–714) h. The post-deaeration pH of EBC samples was significantly lower in ventilated patients than controls (7.50 [7.28–7.70] vs 8.07 [7.60–8.40]; P = 0.008). Ventilation time before sample collection inversely correlated with pH (r = −0.636; P = 0.048). A significantly higher concentration of nitrogen oxide (μM) was seen in ventilated patients vs controls (66.22 [22.26–83.13] vs 15.06 [10.73–23.30]; P = 0.002), whereas levels of 8-isoprostane (pg/mL) were not significantly different between both groups (5.73 [4.0–11.4] vs 9.09 [6.63–11.43]; P = 0.169). The nitrogen oxide concentration correlated negatively with dynamic compliance (r = −0.952; P < 0.001) and positively with respiratory rate (r = 0.683; P = 0.029).

Conclusions

EBC analysis is a non-invasive technique that can be used to monitor ventilated patients. Mechanically ventilated patients had higher EBC acidity and nitrogen oxide concentrations. Duration of ventilation correlated with breath condensate pH.

Keywords

Mechanical ventilation
Exhaled breath condensate
Biomarkers
Ventilator-associated lung injury

Cited by (0)