<qa>  What is the acute respiratory distress syndrome?The acute respiratory distress syndrome ARDS developing after thoracic surgery is usually a lethal complication. The use of corticosteroid in ARDS has been the subject of great controversy and debate over the years. Unfortunately, trials of short-term, high-dose steroid therapy failed to show an improvement in mortality of patients at risk of, or with early, ARDS. Several investigators have suggested that the use of corticosteroids in the late or fibroproliferative phase of ARDS improved lung function and survival. 