La réparation alvéolaire est-elle responsable des modifications de mécanique respiratoire observées au cours du SDRAÂ ?

The acute respiratory distress syndrome (ARDS) is the most severe response to pulmonary aggression. The recovery of a normal respiratory function requires a proper lung consolidation. Consolidation involves an intense fibroproliferative phase that occurs early in the course of the disease. Nevertheless, lung consolidation highly depends on the balance between matrix deposition and degradation. Historically, the alterations of respiratory mechanics in the ARDS, and mainly the reduction in pulmonary compliance, have been mostly related to lung volume reduction. This reduction of normally aerated lung areas has been evidenced by CT scan and led to the “baby lung” concept. More recent works have suggested a relationship between lung matrix turnover and respiratory system compliance. More precisely, a strong collagen deposition correlates with a lower respiratory system compliance. These data are relevant with regards for the fact that ARDS patients with high markers of collagen lung deposition seem to have a more severe prognosis. Finally, the involvement of these results in the potential indication of steroids in ARDS patients will need further investigations.