Advertisement

Intensive Care Medicine

, Volume 29, Issue 2, pp 233–240 | Cite as

Estimation of regional lung volume changes by electrical impedance pressures tomography during a pressure-volume maneuver

  • Huibert R. van Genderingen
  • Adrianus J. van Vught
  • Jos R. C. Jansen
Original

Abstract

Objective

To assess the degree of linearity between lung volume and impedance change by electrical impedance tomography (EIT) in pigs with acute lung injury and to investigate regional impedance changes during a pressure-volume maneuver.

Design and setting

Experimental animal study in a university research laboratory.

Patients and participants

Nine pigs with lung injury induced by lung lavage.

Interventions

The lungs were insufflated to four different lung volumes. Next the lungs were inflated in steps up to 40 cmH2O and then in steps deflated.

Measurements and results

EIT measurements were performed. Impedance was highly linear with lung volume ( r 2=0.97). From the pressure-volume maneuver regional pressure-impedance (P-I) curves were obtained in the upper half (ventral) and lower half (dorsal) of the thoracic cross-section. Excellent fit was found of the regional P-I curves with a predefined sigmoid equation ( r 2=0.998). The P-I curves after lavage were markedly different than before lavage. The P-I curves recorded after lavage displayed a strong heterogeneity on the inflation limb: Lower corner pressure (traditionally lower inflection point) was significantly higher in the dorsal (28.3±4.1 cmH2O) than in the ventral region (17.5±4.3 cmH2O). The deflation limb displayed a more homogeneous pattern. Upper corner pressure and true inflection point, where the curve slope is maximal, in the dorsal region were only slightly higher than in the ventral region (1–2 cmH2O).

Conclusions

EIT and automated curve fitting provide information on regional lung inflation and deflation which may be of clinical use for optimizing ventilator settings.

Keywords

Acute lung injury Lung volume Lung compliance Electrical impedance Tomography 

Notes

Acknowledgements

We are grateful to Arnold Drop and Els Duval for their assistance during the experiments. We thank Theo Faes and Rob Heethaar for their comments on the interpretation of EIT and Dick Markhorst for general discussion. The help of Tom Leenhoven in the setup of the experiments is greatly appreciated.

References

  1. 1.
    Lachmann B (1992) Open the lung and keep the lung open. Intensive Care Med 118:319–321Google Scholar
  2. 2.
    Amato MB, Barbas CS, Medeiros DM, Magaldi RB, Schettino GP, Lorenzi-Filho G, et al (1998) Effect of a protective-ventilation strategy on mortality in the acute respiratory distress syndrome. N Engl J Med 338:347–354PubMedGoogle Scholar
  3. 3.
    Gattinoni L, Pelosi P, Crotti S, Valenza F (1995) Effects of positive end-expiratory pressure on regional distribution of tidal volume and recruitment in adult respiratory distress syndrome. Am J Respir Crit Care Med 151:1807–1814PubMedGoogle Scholar
  4. 4.
    Gattinoni L, Pesenti A, Avalli L, Rossi F, Bombino M (1987) Pressure-volume curve of total respiratory system in acute respiratory failure. Computed tomographic scan study. Am Rev Respir Dis 136:730–736PubMedGoogle Scholar
  5. 5.
    Hahn G, Spinova I, Baisch F, Hellige G (1995) Changes in the thoracic impedance under different ventilatory conditions. Physiol Meas 16: A161–A173CrossRefPubMedGoogle Scholar
  6. 6.
    Nopp P, Rapp E, Pfutzner H, Nakesch H, Ruhsam C (1993) Dielectric properties of lung tissue as a function of air content. Phys Med Biol 38:699–716CrossRefPubMedGoogle Scholar
  7. 7.
    Kunst PW, Bohm SH, Vazquez de Anda G, Amato MB, Lachmann B, Postmus PE, de Vries PM (2000) Regional pressure volume curves by electrical impedance tomography in a model of acute lung injury. Crit Care Med 28:178–183PubMedGoogle Scholar
  8. 8.
    Hickling KG (1998) The pressure-volume curve is greatly modified by recruitment. A mathematical model of ARDS lungs. Am J Respir Crit Care Med 158:194–202PubMedGoogle Scholar
  9. 9.
    Barber DC and Brown BH (1984) Applied potential tomography. J Phys [E] 17:723–733Google Scholar
  10. 10.
    Hahn G, Frerichs I, Kleyer M, Hellige G (1996) Local mechanics of the lung tissue determined by functional EIT. Physiol Meas 17 [Suppl 4A]:A159–A166Google Scholar
  11. 11.
    Jansen JRC, Hoorn E, Goudoever J van, Versprille A (1989) A computerized respiratory system including test functions of lung and circulation. J Appl Physiol 67:1687–1691PubMedGoogle Scholar
  12. 12.
    Guyton AC (1986) Textbook of medical physiology. 7th edn. Saunders, Philadelphia, pp 481–503Google Scholar
  13. 13.
    Jansen JR, Versprille A (1986) Improvement of cardiac output estimation by the thermodilution method during mechanical ventilation. Intensive Care Med 12:71–79PubMedGoogle Scholar
  14. 14.
    Grotjohan HP, Heijde RMJL van der (1992) Experimental models of the respiratory distress syndrome: lavage and oleic acid. Thesis, Erasmus University Rotterdam, The Netherlands–Google Scholar
  15. 15.
    Huygen PE, Feenstra BW, Holland WP, Ince C, Stam H, Bruining HA (1990) Design and validation of an indicator gas injector for multiple gas washout tests in mechanically ventilated patients. Crit Care Med 18:754–759PubMedGoogle Scholar
  16. 16.
    Venegas JG, Harris RS, Simon BA (1998) A comprehensive equation for the pulmonary pressure-volume curve. J Appl Physiol 84:389–395PubMedGoogle Scholar
  17. 17.
    Harris RS, Hess DR, Venegas JG (2000) An objective analysis of the pressure-volume curve in the acute respiratory distress syndrome. Am J Respir Crit Care Med 161:432–439Google Scholar
  18. 18.
    Harris ND, Suggett AJ, Barber DC, Brown BH (1987) Applications of applied potential tomography (APT) in respiratory medicine. Clin Phys Physiol Meas 8 [Suppl A]:155–165Google Scholar
  19. 19.
    Adler A, Amyot R, Guardo R, Bates JHT, Berhiaume Y (1997) Monitoring changes in lung air and liquid volumes with electrical impedance tomography. J Appl Physiol 89:1762–1767Google Scholar
  20. 20.
    Frerichs I, Hahn G, Schroder T, Hellige G (1998) Electrical impedance tomography in monitoring experimental lung injury. Intensive Care Med 24:829–836PubMedGoogle Scholar
  21. 21.
    Kunst PW, de Vries PM, Postmus PE, Bakker J (1999) Evaluation of electrical impedance tomography in the measurement of PEEP-induced changes in lung volume. Chest 115:1102–1106PubMedGoogle Scholar
  22. 22.
    Frerichs I, Schiffmann H, Hahn G, Hellige G (2001) Non-invasive radiation-free monitoring of regional lung ventilation in critically ill infants. Intensive Care Med 27:1385–1394CrossRefPubMedGoogle Scholar
  23. 23.
    Hahn G, Thiel F, Dudykevych T, Frerichs I, Gersing E, Schroder T, Hartung C, Hellige G (2001) Quantitative evaluation of the performance of different electrical tomography devices. Biomed Tech (Berl) 46:91–95Google Scholar
  24. 24.
    Crotti S, Mascheroni D, Caironi P, Pelosi P, Ronzoni G, Mondino M, Marini JJ, Gattinoni L (2001) Recruitment and derecruitment during acute respiratory failure: a clinical study. Am J Respir Crit Care Med 164:131–140PubMedGoogle Scholar
  25. 25.
    O'Keefe GE, Gentilello LM, Erford S, Maier RV (1998) Imprecision in lower "inflection point" estimation from static pressure-volume curves in patients at risk for acute respiratory distress syndrome. J Trauma 44:1064–1068PubMedGoogle Scholar
  26. 26.
    Gattinoni L, D'Andrea L, Pelosi P, Vitale G, Pesenti A, Fumagalli R (1993) Regional effects and mechanism of positive end-expiratory pressure in early adult respiratory distress syndrome. JAMA 269:2122–127PubMedGoogle Scholar
  27. 27.
    Pelosi P, D'Andrea L, Vitale G, Pesenti A, Gattinoni L (1994) Vertical gradient of regional lung inflation in adult respiratory distress syndrome. Am J Respir Crit Care Med 149:8–13Google Scholar
  28. 28.
    Goddon S, Fujino Y, Hromi JM, Kacmarek RM (2001) Optimal mean airway pressure during high-frequency oscillation: predicted by the pressure-volume curve. Anesthesiology 94:862–869PubMedGoogle Scholar
  29. 29.
    Holzapfel L, Robert D, Perrin F, Blanc PL, Palmier B, Guerin C (1983) Static pressure-volume curves and effect of positive end-expiratory pressure on gas exchange in adult respiratory distress syndrome. Crit Care Med 11:591–597PubMedGoogle Scholar
  30. 30.
    Acute Respiratory Distress Syndrome Network (2000) Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. N Engl J Med 342:1301–1318PubMedGoogle Scholar

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Huibert R. van Genderingen
    • 1
  • Adrianus J. van Vught
    • 2
  • Jos R. C. Jansen
    • 3
    • 4
  1. 1.Department of Clinical Physics and InformaticsVrije Universiteit Medical CenterAmsterdamThe Netherlands
  2. 2.Pediatric Intensive Care Unit, Department of PediatricsWilhelmina Children's HospitalUtrechtThe Netherlands
  3. 3.Department of Intensive CareLeiden University Medical CenterLeidenThe Netherlands
  4. 4.Pathophysiological Laboratory, Department of Pulmonary DiseasesErasmus UniversityRotterdamThe Netherlands

Personalised recommendations