Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

A new automated method versus continuous positive airway pressure method for measuring pressure–volume curves in patients with acute lung injury



To compare pressure–volume (PV) curves obtained with the Galileo ventilator with those obtained with the CPAP method in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS).


Prospective, observational study.


General critical care center.

Patients and participants

Patients with ALI/ARDS and receiving mechanical ventilation.


Pressure–volume curves were obtained in random order with the CPAP technique and with the software PV Tool-2 (Galileo ventilator).

Measurements and results

In ten consecutive patients, airway pressure was measured by a pressure transducer and changes in lung volume were measured by respiratory inductive plethysmography. PV curves were fitted to a sigmoidal equation with a mean R 2 of 0.994 ± 0.003. Intraclass correlation coefficients were all >0.75 (< 0.001 at all pressure levels). Lower (LIP) and upper inflection (UIP), and deflation maximum curvature (PMC) points calculated from the fitted variables showed a good correlation between methods with intraclass correlation coefficients of 0.98 (0.92, 0.99), 0.92 (0.69, 0.98), and 0.97 (0.86, 0.98), respectively (< 0.001 in all cases). Bias and limits of agreement for LIP (0.51 ± 0.95 cmH2O; −1.36 to 2.38 cmH2O), UIP (0.53 ± 1.52 cmH2O; −2.44 to 3.50 cmH2O), and PMC (−0.62 ± 0.89 cmH2O; −2.35 to 1.12 cmH2O) obtained with the two methods in the same patient were clinically acceptable. No adverse effects were observed.


The PV Tool-2 built into the Galileo ventilator is equivalent to the CPAP method for tracing static PV curves of the respiratory system in critically ill patients receiving mechanical ventilation.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2


  1. 1.

    Lu Q, Rouby JJ (2000) Measurement of pressure volume curves in patients on mechanical ventilation: methods and significance. Crit Care 4:91–100

  2. 2.

    Amato MBP, Amato MB, Barbas CS, Medeiros DM, Magaldi RB, Schettino GP, Lorenzi-Filho G, Kairalla RA, Deheinzelin D, Munoz C, Oliveira R, Takagaki TY, Carvalho CR (1998) Effect of a protective-ventilation strategy on mortality in the acute respiratory distress syndrome. N Engl J Med 38:347–354

  3. 3.

    Villar J, Kacmarek RM, Perez-Mendez L, Aguirre-Jaime A (2006) A high positive end-expiratory pressure, low tidal volume ventilatory strategy improves outcome in persistent acute respiratory distress syndrome: a randomized, controlled trial. Crit Care Med 34:1311–1318

  4. 4.

    Ranieri VM, Suter PM, Tortorella C, De Tullio R, Dayer JM, Brienza A, Bruno F, Slutsky AS (1999) Effect of mechanical ventilation on inflammatory mediators in patients with acute respiratory distress syndrome: a randomized controlled trial. JAMA 282:54–61

  5. 5.

    Terragni PP, Rosboch G, Tealdi A, Corno E, Menaldo E, Davini O, Gandini G, Herrmann P, Mascia L, Quintel M, Slutsky AS, Gattinoni L, Ranieri VM (2007) Tidal hyperinflation during low tidal volume ventilation in acute respiratory distress syndrome. Am J Respir Crit Care Med 175:160–166

  6. 6.

    Roupie E, Dambrosio M, Sevillo G, Mentec H, el Atrous S, Beydon L, Brun-Buisson C, Lemaire F, Brochard L (1995) Titration of tidal volume and induced hypercapnia in acute respiratory distress syndrome. Am J Respir Crit Care Med 152:121–128

  7. 7.

    Albaiceta GM, Luyando LH, Parra D, Menendez R, Calvo J, Pedreira PR, Taboada F (2005) Inspiratory vs expiratory pressure–volume curves to set end-expiratory pressure in acute lung injury. Intensive Care Med 31:1370–1378

  8. 8.

    DiRocco JD, Carney DE, Nieman GF (2007) Correlation between alveolar recruitment/derecruitment and inflection points on the pressure–volume curve. Intensive Care Med 33:1204–1211

  9. 9.

    Bayle F, Guerin C, Debord S, Badet M, Lemasson S, Poupelin JC, Richard JC (2006) Assessment of airway closure from deflation lung volume–pressure curve: sigmoidal equation revisited. Intensive Care Med 32:894–898

  10. 10.

    Albaiceta GM, Piacentini E, Villagra A, Lopez-Aguilar J, Taboada F, Blanch L (2003) Application of continuous positive airway pressure to trace static pressure–volume curves of the respiratory system. Crit Care Med 31:2514–2519

  11. 11.

    Piacentini E, Wysocki M, Ll Blanch (2007) Validation of a new commercially available method to measure static-pressure volume curves at the bedside. Intensive Care Med 33(S2):207

  12. 12.

    Bernard GR, Artigas A, Brigham KL, Carlet J, Falke K, Hudson L, Lamy M, Le Call JR, Morris A, Spragg R, The Consensus Committee (1994) The American–European consensus conference on ARDS. Definition, mechanisms, relevant outcomes, and clinical trial coordination. Am J Respir Crit Care Med 149:818–824

  13. 13.

    Decailliot F, Demoule A, Maggiore SM, Jonson B, Duvaldestin P, Brochard L (2006) Pressure–volume curves with and without muscle paralysis in acute respiratory distress syndrome. Intensive Care Med 32:1322–1328

  14. 14.

    Venegas JG, Harris RS, Simon BA (1998) A comprehensive equation the pulmonary pressure volume curve. J Appl Physiol 84:389–395

  15. 15.

    Bland JM, Altman DG (1986) Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 8476:307–310

  16. 16.

    Bartko JJ (1966) The intraclass correlation coefficient as a measure of reliability. Psychol Rep 19:3–11

  17. 17.

    Chiumello D, Carlesso E, Aliverti A, Dellaca RL, Pedotti A, Pelosi P, Gattinoni L (2007) Effects of volume shift on the pressure–volume curve of the respiratory system in ALI/ARDS patients. Minerva Anestesiol 73:109–118

  18. 18.

    Fernandez R, Blanch L, Artigas A (1993) Inflation static pressure–volume curves of the total respiratory system determined without any instrumentation other than the mechanical ventilator. Intensive Care Med 19:33–38

  19. 19.

    Servillo G, Svantesson C, Beydon L, Roupie E, Brochard L, Lemaire F, Jonson B (1997) Pressure–volume curves in acute respiratory failure. Automated low flow inflation versus occlusion. Am J Respir Crit Care Med 155:1629–1636

  20. 20.

    Lu Q, Vieira S, Richecoeur J, Puybasset L, Kalfon P, Coriat P, Rouby JJ (1999) A simple automated method for measuring pressure volume curve during mechanical ventilation. Am J Respir Crit Care Med 159:275–282

  21. 21.

    Ranieri VM, Giuliani R, Flore T, Dambrosio M, Milic-Emili J (1994) Volume–pressure curve of the respiratory system predicts effects of PEEP in ARDS: ‘occlusion’ versus ‘constant flow’ technique. Am J Respir Crit Care Med 149:19–27

  22. 22.

    Jonson B, Richard JC, Straus C, Mancebo J, Lemaire F, Brochard L (1999) Pressure–volume curves and compliance in acute lung injury: evidence of recruitment above the lower inflection point. Am J Respir Crit Care Med 159:1172–1178

  23. 23.

    Blanch L, Lopez-Aguilar J, Villagra A (2007) Bedside evaluation of pressure–volume curves in patients with acute respiratory distress syndrome. Curr Opin Crit Care 13:332–337

  24. 24.

    Markhorst DG, Van Gestel JP, Van Genderingen HR, Haitsma JJ, Lachmann B, Van Vught AJ (2006) Respiratory inductive plethysmography accuracy at varying PEEP levels and degrees of acute lung injury. J Med Eng Technol 30:166–175

  25. 25.

    Dall’ava-Santucci J, Armaganidis A, Brunet F, Dhainaut JF, Chelucci G, Monsallier J, Lockhart A (1988) Causes of error of respiratory pressure–volume curves in paralyzed subjects. J Appl Physiol 64:42–49

Download references


This work was supported in part by an Educational grant from Hamilton. CIBER of respiratory diseases is an initiative of ISCIII.

Author information

Correspondence to Lluis Blanch.

Additional information

An erratum to this article is available at

Electronic supplementary material

Below is the link to the electronic supplementary material.

Figures 1e–5e (DOC 124 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Piacentini, E., Wysocki, M. & Blanch, L. A new automated method versus continuous positive airway pressure method for measuring pressure–volume curves in patients with acute lung injury. Intensive Care Med 35, 565–570 (2009).

Download citation


  • Acute lung injury
  • Acute respiratory distress syndrome
  • Static pressure–volume curves of the respiratory system
  • Continuous airway positive pressure
  • Mathematical fitting of respiratory data