This Article Full Text Full Text (PDF) All Versions of this Article: 29/3/496    most recent 09031936.00084006v1 Alert me when this article is cited Alert me if a correction is posted Permissions Request Permissions Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (30) Citing Articles via Google Scholar Google Scholar Articles by Kullmann, T. Articles by Horváth, I. Search for Related Content PubMed PubMed Citation Articles by Kullmann, T. Articles by Horváth, I.

Exhaled breath condensate pH standardised for CO₂ partial pressure

¹ Dept of Pathophysiology and, ³ Clinical Laboratory, National Korányi Institute for Tuberculosis and Pulmonology, and ² Institute of Human Physiology and Clinical Experimental Research, Semmelweis University, Budapest, Hungary.

CORRESPONDENCE: I. Horváth, Dept of Human Physiology and Clinical Experimental Research, Semmelweis University, 1082 Budapest Üllüi u. 78/a Hungary. Fax: 36 13343162. E-mail: kiss.horvath{at}t-online.hu

Keywords: Airway biology, airway inflammation, breath test, exhaled biomarkers, exhaled breath condensate

Received: June 27, 2006
Accepted October 23, 2006

Exhaled breath condensate (EBC) pH is considered to reflect the acid-base balance of the airways. Current pH measurements do not take into account the effect of CO₂. The aim of the present study was to determine the effect of condensate CO₂ partial pressure on pH and to provide a more precise mode of EBC pH determination.

Condensate pH and CO₂ partial pressure were measured in parallel from 12 healthy volunteers and 12 asthmatics using a blood gas analyser in neat, argon de-aerated and CO₂-loaded samples. The regression analysis was used to test the relationship between pH and CO₂, and to calculate the pH at a CO₂ level of 5.33 kPa (physiological alveolar CO₂ partial pressure). Reproducibility of different pH readings was compared using the Bland–Altman test.

Condensate CO₂ concentration was variable both in neat and argon de-aerated samples. There was a close negative logarithmic relationship between CO₂ and pH. Calculation of pH at a CO₂ level of 5.33 kPa provided reproducibility approximately six times as good as that of the currently used measurements.

Condensate CO₂ partial pressure influences pH measurements. Determination of pH at a standard CO₂ level provides the most reproducible condensate pH values to date.

This article has been cited by other articles:

				I. Horvath, Z. Lazar, N. Gyulai, M. Kollai, and G. Losonczy Exhaled biomarkers in lung cancer Eur. Respir. J., July 1, 2009; 34(1): 261 - 275. [Abstract] [Full Text] [PDF]

				L. Prieto, S. Esnal, V. Lopez, D. Barato, R. Rojas, and J. Marin Maximal Response Plateau to Adenosine 5'-Monophosphate in Asthma: Relationship With the Response to Methacholine, Exhaled Nitric Oxide, and Exhaled Breath Condensate pH Chest, June 1, 2009; 135(6): 1521 - 1526. [Abstract] [Full Text] [PDF]

				M.-J. Cruz, S. Sanchez-Vidaurre, P.-V. Romero, F. Morell, and X. Munoz Impact Of Age on pH, 8-Isoprostane, and Nitrogen Oxides in Exhaled Breath Condensate Chest, February 1, 2009; 135(2): 462 - 467. [Abstract] [Full Text] [PDF]

				Z. L. Borrill, K. Roy, and D. Singh Exhaled breath condensate biomarkers in COPD Eur. Respir. J., August 1, 2008; 32(2): 472 - 486. [Abstract] [Full Text] [PDF]

				T. Kullmann, I. Barta, B. Antus, M. Valyon, and I. Horvath Environmental temperature and relative humidity influence exhaled breath condensate pH Eur. Respir. J., February 1, 2008; 31(2): 474 - 475. [Full Text] [PDF]

				S. Dodig, I. Cepelak, D. Plavec, Z. Vlasic, B. Nogalo, and M. Turkalj The effect of gas standardisation on exhaled breath condensate pH and PCO2 Eur. Respir. J., July 1, 2007; 30(1): 185 - 187. [Full Text] [PDF]

				I. Horvath From the authors Eur. Respir. J., July 1, 2007; 30(1): 187 - 187. [Full Text] [PDF]