High-frequency oscillatory ventilation in premature infants with respiratory failure: a preliminary report.

High-frequency ventilation has been used successfully to manage life-threatening complications in premature infants with lung disease. Here we report a preliminary assessment of the efficacy and safety of high-frequency oscillatory ventilation-(HFO-A, A = active expiratory phase) when used as a primary ventilator in 11 infants of 24-34 weeks gestation who required ventilatory support. HFO-A was initiated after no more than 5.5 hr of conventional mechanical ventilation (CMV). HFO-A at 15 Hz was used for 12-203 hr following a protocol designed for rapid reduction of FI02 requirements. CO2 elimination was easily achieved in all infants. Oxygenation was satisfactory, except in one infant with congenital pneumonia. There were four deaths during HFO-A: two pulmonary (one congenital pneumonia; one pulmonary hemorrhage) and two nonpulmonary. The HFO-A protocol utilized lung volume recruitment maneuvers plus mean airway pressures (MAwP) greater than those generally used early in the course of CMV. Therefore, in a subset of infants less than or equal to 29 weeks' gestation with respiratory distress syndrome (RDS), ventilator pressures and gas exchange were compared in infants treated with either HFO-A or CMV. Maximum MAwP levels were reached earlier in six infants on HFO-A (5.2 +/- 2.5 hr; mean +/- SD) than in a comparable group of 9 CMV-treated infants (36 +/- 1 hr). This earlier use of high MAwP lowered the FI02 to less than 0.4 by 18.9 +/- 11 hr with HFO-A as compared with 64 +/- 6 hr using CMV, without any evidence of an increase in pulmonary complications. There were 17 complications in the nine CMV-treated infants; and four in the six HFO-A treated ones. We conclude that HFO-A, instituted early and used with a protocol designed for early reduction in FI02 requirements, demonstrates sufficient efficacy and safety to warrant further clinical trials in the routine management of infant RDS.