Prone positioning is most likely to improve this patient's chance of survival. This patient has severe acute respiratory distress syndrome (ARDS) due to viral pneumonia, which has significantly impaired oxygenation. A randomized controlled trial has shown that survival was dramatically improved for patients who were placed in the prone position for at least 16 hours per day until their oxygenation improved, compared with patients who were managed identically except for being kept in the supine position. In the study, the 90-day mortality in the group with prone positioning was 23.6%, whereas it was 41% in the supine group. This technique was not associated with increased adverse consequences. The mechanisms by which prone positioning improves oxygenation are likely multifactorial, with optimization of ventilation-perfusion matching likely playing a major role. Therefore, for this patient with severe ARDS, the best option is daily prone positioning based on its demonstrated benefit in improving oxygenation and reducing mortality.

Aerosolized surfactant has been used in infant respiratory distress syndrome, but trials of this therapy in adults have not shown benefit.

Nitric oxide dilates the pulmonary vasculature when administered by inhalation and may have a role in treating patients with pulmonary arterial hypertension. In studies of patients with ARDS, inhaled nitric oxide has been shown to improve oxygenation by temporarily improving ventilation-perfusion mismatch; however, a mortality benefit has not been demonstrated in patients with ARDS. It would therefore not be the most appropriate next step in the management of this patient.

Studies of glucocorticoids in ARDS have shown inconsistent results and have not generally demonstrated improved outcomes. Therefore, systemic glucocorticoids would not be an optimal therapy for treating this patient.