Abstract 1247 Poster Session I, Saturday, 5/1 (poster 20)

Hypothesis: early use of HFOV in infants of GA < 30 wks with RDS will result in: 1) less infants requiring ≥2 instillations of exogenous surfactant (Curosurf®); 2) less infants requiring oxygen at 28 days and 36 wks post-menstrual age; 3) no difference in occurrence of severe intraventricular hemorrhage (IVH grades 3-4).

Methods: Infants of GA 24-29 wks (stratification: 24-27 and 28-29 wks) who needed CV before 6 hours of life, due to RDS, were randomly assigned to HFOV (same piston oscillator in all cases) or CV, until extubation or treatment failure, or for 10 days. Curosurf® was used in all cases following randomization, after optimization of lung volume in the HFOV group. The expected sample size for showing a 50% reduction in the number of cases requiring ≥2 Curosurf® instillations, was 250 patients (α=0.05; β=0.2).

Results: 292 infants were randomized, at 144 minutes of life (median). Preliminary results are available for 262 cases. 148 infants were of GA 24-27 wks (median 26wks 5d) and 114 infants were of GA 28-29 wks (29wks Od). Characteristics of the 2 groups were similar. Comparison of the 2 groups (HFOV n=134 vs CV n=128) showed: 1)≥2 instillations of Curosurf® were needed in 42 (31%) and 78 infants (61%), respectively (p<0.001); 2) Requirement of oxygen at 28 days was not different (45 and 42%, NS). (Results for oxygen at 36 wks not yet available); 3) IVH grades 3-4 were observed after randomization in 33 (25%) vs 19 cases (15%) (p=0.054). Deaths by age 28 days: 33 in HFOV (IVH 3-4: 20 of 33) and 28 in CV group (IVH 3-4: 15 of 28).

Conclusion: Early use of HFOV compared with CV in the treatment of RDS is associated with a decrease in exogenous surfactant requirement, without influence on oxygen requirement at 28 days. In contrast with our initial expectations, occurrence of severe IVH appears somewhat more frequent with HFOV. The validity of this finding will be carefully examined.

Supported by Assistance Publique-Hopitaux de Paris. Funded by Serono France and Plan Hospitalier de Recherche Clinique.