High frequency oscillatory ventilation and extracorporeal membrane oxygenation in severe persistent pulmonary hypertension of the newborn.

We report on 50 term and near-term neonates (birth weight greater than 1800 g, gestational age greater than 33 weeks) with severe persistent pulmonary hypertension of the newborn (PPHN), referred to us from January 1987 to July 1991 after failure of maximum conventional treatment. All infants had paO2 less than 45 mm Hg when ventilated with peak inspiratory pressure greater than 38 cm H2O and FiO2 = 1.0, hence meeting entry criteria for extracorporeal membrane oxygenation (ECMO). High frequency oscillatory ventilation (HFOV) was tried in all patients. If sufficient oxygenation could not be achieved (paO2 less than 40 mm Hg for at least 2 h), ECMO therapy was begun, which was the case in 25 children. Neonates responding to HFOV (n = 25) were of a slightly younger gestational age (37.0 weeks vs 38.8 weeks, P less than 0.05), had higher Apgar scores and were less hypoxaemic before HFOV (paO2 36.6 mm Hg vs 28.8 mm Hg, P less than 0.01); during HFOV there was a significant rise in paO2 (greater than 150 mm Hg; P less than 0.001) and a fall in pCO2 to 21.6 mm Hg (P less than 0.001). Due to air leaks, which was the main complication of HFOV (52%), ECMO therapy had to be begun in two additional infants after an initial positive effect. HFOV tended to be successful in cases of primary PPHN, meconium aspiration and sepsis, but not in infants with lung hypoplasia as a result of diaphragmatic hernia or other reasons. Success or failure of HFOV could not be reliably predicted by any parameter.(ABSTRACT TRUNCATED AT 250 WORDS)