AJP - Lung Columbus Instruments
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Lung Cell Mol Physiol 294: L1021-L1022, 2008. First published April 25, 2008; doi:10.1152/ajplung.90279.2008
1040-0605/08 $8.00
This Article
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
294/6/L1021    most recent
90279.2008v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Web of Science (1)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Matthay, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Matthay, M. A.

EDITORIAL FOCUS

Measurement of extravascular lung water in patients with pulmonary edema

Michael A. Matthay

Departments of Medicine and Anesthesia and The Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California

MEASUREMENT OF EXTRAVASCULAR lung water has been a topic of major interest for more than two decades (1, 5, 19). In the recent article by Effros et al. (2), they provide a review of current and past efforts to measure extravascular lung water with thermal and osmotic dilution methods. The authors discuss several of the limitations of these methods, including problems related to early recirculation of the thermal indicator, as well as potential problems related to heterogeneous perfusion of edematous lungs. Although the authors have provided a thoughtful critique of some of the limitations of the transpulmonary thermodilution technique for measuring extravascular lung water, there is some recent evidence that this methodology may provide valuable insights into lung fluid balance in patients with acute pulmonary edema and acute lung injury.

In 2006, Perkins et al. (13) published the results of a randomized placebo-controlled clinical trial in which 40 patients with acute lung injury were treated with either intravenous salbutamol (a β2-agonist) or placebo. The primary objective of the trial was to determine if the β-agonist reduced extravascular lung water in these patients. β-agonist therapy has been proposed as a treatment that may accelerate the resolution of alveolar edema by upregulating salt and water transport mechanisms in the alveolar epithelium (3, 4). The results of this blinded trial showed that the patients who were treated with intravenous salbutamol had a 40% reduction in extravascular lung water compared with the controls. The reduction in extravascular lung water was matched by a reduction in the plateau airway pressure, a measure of quasistatic respiratory compliance that may reflect less pulmonary edema. In spite of the methodological concerns pointed out by Effros et al. (2), the results of this blinded trial seemed to indicate that the transpulmonary thermodilution technique (PiCCO; Pulsion Medical Systems, Munich, Germany) is able to detect a significant change in lung water with a treatment that might be expected to achieve this objective.

In addition, the results of a recent clinical trial published in April 2008 also support the conclusion that this methodology for measuring extravascular lung water is able to detect clinically significant changes in lung water (8). In this trial, the patients had their extravascular lung water measured before surgical resection of a lung lobe for cancer, and then the extravascular lung water was measured again every 6 h postoperatively. The patients were randomized in an elegant crossover design to receive every 6 h either 5 mg of inhaled salbutamol (β2-agonist) or 0.5 mg of inhaled ipratroprium. When patients were treated with inhaled salbutamol, there was an 18% reduction in extravascular lung water (P = 0.019) and a corresponding improvement in oxygenation (P = 0.012). The results of this study provide further evidence that the measurement of extravascular lung water with this transpulmonary thermodilution technique is sensitive to detecting changes in the quantity of pulmonary edema in patients with pulmonary edema.

It should also be noted that several investigators have tested the reliability of the extravascular lung water measurement compared with gravimetric measurements in animal models and in patients (6, 7, 9, 15–18). Most of these studies have found a good correlation with gravimetric measurements. Also, a recent study from Phillips et al. (14) reported that the combined measurement of extravascular lung water and pulmonary dead space in patients with acute lung injury has prognostic value for identifying patients at the highest risk of nonsurvival. In fact, extravascular lung water that was greater than 16 ml/kg/predicted body weight predicted death with 100% specificity and 86% sensitivity. The use of predicted body weight for indexing extravascular lung water measurements may increase the accuracy of this method because of the prevalence of obesity in European and U.S. populations (11, 12).

In summary, the concerns expressed by Effros et al. (2) regarding the methodological issues with measurement of extravascular lung water are important to appreciate. However, the results of experimental studies, observational clinical studies, and two double-blind controlled trials indicate that significant changes in extravascular lung water can be detected in patients, and therefore measurements of lung water have research value (8, 13). The studies by the late Dr. Schuster and his colleagues (10) almost 20 years ago suggested the potential benefit of measuring extravascular lung water as a method for improving clinical outcomes. Thus, in my opinion, further studies are needed to assess extravascular lung water in patients at risk for developing pulmonary edema as well as in patients with established pulmonary edema from hydrostatic causes or from an increase in permeability (acute lung injury). Reliance on the chest radiograph or arterial oxygenation is not adequate for assessing the quantity of pulmonary edema. The transpulmonary thermodilution technique should be used to advance research into the mechanisms and potential therapeutic strategies in patients who are at risk for developing pulmonary edema from acute lung injury as well as in patients with established acute lung injury.


   FOOTNOTES
 

Address for reprint requests and other correspondence: M. A. Matthay, Univ. of California, San Francisco Cardiovascular Research Institute, 505 Parnassus Ave., M-917, San Francisco, CA 94143-0624 (e-mail: michael.matthay{at}ucsf.edu)


   REFERENCES
TOP
 REFERENCES
 

  1. Chinard FP, Enns T. Transcapillary pulmonary exchange of water in the dog. Am J Physiol 178: 197–202, 1954.[Free Full Text]
  2. Effros RM, Pornsuriyasak P, Porszasz J, Casaburi R. Indicator dilution measurements of extravascular lung water: basic assumptions and observations. Am J Physiol Lung Cell Mol Physiol (March 21, 2008). doi: 10.1152/ajplung.00533.2007.[Abstract/Free Full Text]
  3. Folkesson HG, Matthay MA. Alveolar epithelial ion and fluid transport: recent progress. Am J Respir Cell Mol Biol 35: 10–19, 2006.[Free Full Text]
  4. Guidot DM, Folkesson HG, Jain L, Sznajder JI, Pittet JF, Matthay MA. Integrating acute lung injury and regulation of alveolar fluid clearance. Am J Physiol Lung Cell Mol Physiol 291: L301–L306, 2006.[Abstract/Free Full Text]
  5. Isakow W, Schuster DP. Extravascular lung water measurements and hemodynamic monitoring in the critically ill: bedside alternatives to the pulmonary artery catheter. Am J Physiol Lung Cell Mol Physiol 291: L1118–L1131, 2006.[Abstract/Free Full Text]
  6. Katzenelson R, Perel A, Berkenstadt H, Preisman S, Kogan S, Sternik L, Segal E. Accuracy of transpulmonary thermodilution versus gravimetric measurement of extravascular lung water. Crit Care Med 32: 1550–1554, 2004.[CrossRef][Web of Science][Medline]
  7. Kirov MY, Kuzkov VV, Kuklin VN, Waerhaug K, Bjertnaes LJ. Extravascular lung water assessed by transpulmonary single thermodilution and postmortem gravimetry in sheep. Crit Care 8: R451–R458, 2004.[CrossRef][Web of Science][Medline]
  8. Licker M, Tschopp JM, Robert J, Frey JG, Diaper J, Ellenberger C. Aerosolized salbutamol accelerates the resolution of pulmonary edema after lung resection. Chest 133: 845–852, 2008.[CrossRef][Web of Science][Medline]
  9. Mihm FG, Feeley TW, Rosenthal MH, Lewis F. Measurement of extravascular lung water in dogs using the thermal-green dye indicator dilution method. Anesthesiology 57: 116–122, 1982.[Web of Science][Medline]
  10. Mitchell JP, Schuller D, Calandrino FS, Schuster DP. Improved outcome based on fluid management in critically ill patients requiring pulmonary artery catheterization. Am Rev Respir Dis 145: 990–998, 1992.[Web of Science][Medline]
  11. Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, 1999–2004. JAMA 295: 1549–1555, 2006.[Abstract/Free Full Text]
  12. Patroniti N, Bellani G, Maggioni E, Manfio A, Marcora B, Pesenti A. Measurement of pulmonary edema in patients with acute respiratory distress syndrome. Crit Care Med 33: 2547–2554, 2005.[CrossRef][Web of Science][Medline]
  13. Perkins GD, McAuley DF, Thickett DR, Gao F. The beta-agonist lung injury trial (BALTI): a randomized placebo-controlled clinical trial. Am J Respir Crit Care Med 173: 281–287, 2006.[Abstract/Free Full Text]
  14. Phillips CR, Chesnutt MS, Smith SM. Extravascular lung water in sepsis-associated acute respiratory distress syndrome: indexing with predicted body weight improves correlation with severity of illness and survival. Crit Care Med 36: 69–73, 2008.[Web of Science][Medline]
  15. Roch A, Michelet P, Lambert D, Delliaux S, Saby C, Perrin G, Ghez O, Bregeon F, Thomas P, Carpentier JP, Papazian L, Auffray JP. Accuracy of the double indicator method for measurement of extravascular lung water depends on the type of acute lung injury. Crit Care Med 32: 811–817, 2004.[CrossRef][Web of Science][Medline]
  16. Rossi P, Wanecek M, Rudehill A, Konrad D, Weitzberg E, Oldner A. Comparison of a single indicator and gravimetric technique for estimation of extravascular lung water in endotoxemic pigs. Crit Care Med 34: 1437–1443, 2006.[CrossRef][Web of Science][Medline]
  17. Sakka SG, Ruhl CC, Pfeiffer UJ, Beale R, McLuckie A, Reinhart K, Meier-Hellmann A. Assessment of cardiac preload and extravascular lung water by single transpulmonary thermodilution. Intensive Care Med 26: 180–187, 2000.[CrossRef][Web of Science][Medline]
  18. Schuster DP, Calandrino FS. Single versus double indicator dilution measurements of extravascular lung water. Crit Care Med 19: 84–88, 1991.[Web of Science][Medline]
  19. Staub NC, Hyde RW, Crandall E. NHLBI workshop summary. Workshop on techniques to evaluate lung alveolar-microvascular injury. Am Rev Respir Dis 141: 1071–1077, 1990.[Web of Science][Medline]




This Article
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
294/6/L1021    most recent
90279.2008v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Web of Science (1)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Matthay, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Matthay, M. A.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2008 by the American Physiological Society.