Intensive Care Medicine

, Volume 31, Issue 2, pp 220–226

Prone position improves mechanics and alveolar ventilation in acute respiratory distress syndrome

  • Antoine Vieillard-Baron
  • Anne Rabiller
  • Karin Chergui
  • Olivier Peyrouset
  • Bernard Page
  • Alain Beauchet
  • François Jardin
Original

DOI: 10.1007/s00134-004-2478-z

Cite this article as:
Vieillard-Baron, A., Rabiller, A., Chergui, K. et al. Intensive Care Med (2005) 31: 220. doi:10.1007/s00134-004-2478-z

Abstract

Objective

We tested the hypothesis that ventilation in the prone position might improve homogenization of tidal ventilation by reducing time-constant inequalities, and thus improving alveolar ventilation. We have recently reported in ARDS patients that these inequalities are responsible for the presence of a “slow compartment,” excluded from tidal ventilation at supportive respiratory rate.

Design

In 11 ARDS patients treated by ventilation in the prone position because of a major oxygenation impairment (PaO2/FIO2≤100 mm Hg) we studied mechanical and blood gas changes produced by a low PEEP (6±1 cm H2O), ventilation in the prone position, and the two combined.

Results

Ventilation in the prone position significantly reduced the expiratory time constant from 1.98±0.53 s at baseline with ZEEP to 1.53±0.34 s, and significantly decreased PaCO2 from 55±11 mm Hg at baseline with ZEEP to 50±7 mm Hg. This improvement in alveolar ventilation was accompanied by a significant improvement in respiratory system mechanics, and in arterial oxygenation, the latter being markedly increased by application of a low PEEP (PaO2/FIO2 increasing from 64±19 mm Hg in supine position with ZEEP to 137±88 mm Hg in prone with a low PEEP).

Conclusion

In severely hypoxemic patients, prone position was able to improve alveolar ventilation significantly by reducing the expiratory time constant.

Keywords

ARDSProne positionSlow compartmentTime constantCompliance

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • Antoine Vieillard-Baron
    • 1
  • Anne Rabiller
    • 1
  • Karin Chergui
    • 1
  • Olivier Peyrouset
    • 1
  • Bernard Page
    • 1
  • Alain Beauchet
    • 2
  • François Jardin
    • 1
  1. 1.Medical Intensive Care UnitUniversity Hospital Ambroise Paré, Assistance Publique Hôpitaux de ParisBoulogne CedexFrance
  2. 2.Department of BiostatisticsUniversity Hospital Ambroise ParéBoulogne CedexFrance