[Induction of fetal lung maturation using ambroxol and betamethasone. Results of an open multicenter study]

Abstract

In a randomized open multicenter study the results of antenatal prophylaxis against neonatal RDS by administration of betamethasone were compared with those obtained with the bromhexine VIII metabolite Ambroxol. Ambroxol was administered for a maximum of 5 days - 1000 mg in an infusion solution; betamethasone was injected intramuscularly in 2 daily doses of 8 mg. One of these two substances was given to 123 pregnant women for pulmonary maturation in the fetus, in accordance with a randomization plan. The patients were either being treated for premature labor or pregnancy was terminated on the basis of indication between the 28th and 36th week. Therapy had to be discontinued in 4 cases in each group, because of continued labor and birth, and in one case because of an amniotic infection syndrome. A full analysis of the treatment records of 57 pregnancies in the Ambroxol group was carried out; the corresponding figure for the betamethasone group was 58. In 39 patients the duration of pregnancy was 37 weeks or more, so that no assessment on the basis of neonatal pulmonary maturity was possible. In the remaining pregnancies, RDS morbidity was estimated on the basis of clinical and radiological findings and blood gas analysis. Related to a maximum duration of pregnancy of 34 weeks, RDS morbidity after Ambroxol therapy was 18.2% (2 out of 11), as opposed to 35.7% (5 out of 14) after betamethasone treatment. The results confirm that antenatal administration of Ambroxol can bring about a reduction in neonatal RDS corresponding to that achieved with betamethasone therapy. However, with Ambroxol the occurrence of side-effects is potentially lower; it therefore has advantages over betamethasone while being equally efficacious.