Role of open-lung biopsy in acute respiratory distress syndrome

When classic examinations such as bronchoalveolar lavage are not contributory in the etiologic diagnosis of unresolving acute respiratory distress syndrome, surgical lung biopsy would appear to be useful to determine the specific cause, particularly infection or postaggressive fibrosis, which could benefit from an adapted treatment.

Postaggressive pulmonary fibrosis is a possible evolution for unresolving acute respiratory distress syndrome and its association with a poor prognosis has been demonstrated. The administration of corticoids would make it possible to improve certain ventilatory parameters as well as the prognosis in the fibroproliferation stage. No clinical or usual microbiological criterion can confirm both the existence of fibrosis and nosocomial pneumonia. Biological markers for fibrosis such as procollagen III are not validated to confirm the appearance of a postaggressive fibrosis. A recent study has shown that surgical lung biopsy performed in patients with unresolving acute respiratory distress syndrome led to a therapeutic modification in 78% of the cases and made it possible to avoid empiric corticotherapy in nearly 50% of the cases considering the absence of fibrosis.

Surgical lung biopsy could be proposed for patients with unresolving acute respiratory distress syndrome after 7-10 days of evolution despite well-conducted initial treatment when the etiology of acute respiratory distress syndrome has not been confirmed or when the appearance of postaggressive fibrosis is suspected.