Abstract:  Acute respiratory distress syndrome (ARDS) is an acute respiratory failure characterized by progressive respiratory dyspnea and intractable hypoxemia caused by various causes both inside and outside the lungs. At present, there is still controversy about the monitoring of prone position（PP）ventilation in patients with severe hypoxemia. This article summarized a case of severe ARDS with type A H1N1 severe pneumonia treated with PP ventilation to improve oxygenation, so as to provide reference for clinical treatment.

Key words: prone position, mechanical ventilation, influenza A virus, H1N1 subtype, acute respiratory distress syndrome, oxygenation index