OXYGENATION IMPROVEMENT WITH NITRIC-OXIDE IN RIGHT-TO-LEFT SHUNT WITHOUT SIGNIFICANT EFFECTS ON PULMONARY ARTERIAL-PRESSURE

Following surgical closure of an interventricular communication compli cating an anterior myocardial infarction, a 74-year-old woman develope d severe right ventricular failure and hypoxemia due to the opening of a patent foramen ovale (PFO). Mean pulmonary artery pressure was 24 m m Hg. Treatment with inhaled nitric oxide (5 ppm) increased PaO2 from 47 to 90 mm Hg (Flo(2) 1). The present observation points out that nit ric oxide inhalation could be useful in the management of severe hypox emia from a right-to-left shunt due to a PFO even when there is no sig nificant pulmonary hypertension present.