Rescue therapy with inhaled nitric oxide in critically ill patients with severe hypoxemic respiratory failure (Brief report)

Purpose To evaluate the efficacy of inhaled nitric oxide (iNO) on oxygenation, shunt, and pulmonary vascular resistance index (PVRI) in severely hypoxemic, ventilated patients. Methods In a two-period double-blind crossover design, 14 critically ill, hypoxemic, ventilated patients were randomized to receive iNO 10 ppm in 100% oxygen or no iNO in 100% oxygen for 30 min followed by a 30-min washout period and then crossed over to the other intervention. Responders to iNO then received iNO, which was increased from 5 ppm to 25 ppm in 5 ppm increments. Severity of illness scores and cardiorespiratory variables were measured. Results Nitric oxide decreased shunt ( P = 0.002) and PVBI ( P = 0.033) and increased oxygenation ( P = 0.011) although the latter two were not statistically significant after adjustment for multiple comparisons. Treatment by period interactions were observed. Conclusion Our findings suggest that iNO improves oxygenation to a clinically significant extent in critically ill patients who are severely hypoxemic.