Inhaled nitric oxide in acute lung disease.

The recognition that inhaled nitric oxide (NO.) selectively vasodilates the pulmonary vasculature and the fact that pulmonary artery hypertension appears to play a pivotal and central role in the clinical manifestations of adult respiratory distress syndrome have led to an explosion of interest in this treatment modality. Improved pulmonary function and reduced ventilatory support have been noted in some patients with acute lung disease treated with inhaled NO.. The efficacy of inhaled NO. in various animal models has been inconsistent. Although it appears likely that inhaled NO. will be a useful adjunct in the treatment of patients with acute lung disease, the appropriate role of inhaled NO. in the treatment of ARDS remains uncertain. In order for inhaled NO. to be clinically useful in patients, this modality will have to be combined with other treatments that alter the florid inflammatory response. One should anticipate the most benefit in patients in whom respiratory failure is secondary to pressure-driven pulmonary edema and true intrapulmonary shunt.