OBJECTIVEAmbroxol induces the synthesis of surfactant in lung alveolar type II cells. Some studies have shown its effectiveness for the prevention of respiratory distress syndrome (RDS) in preterm infants. This study aimed to compare the efficacy of two different ways of ambroxol administration, ie, intravenous injection and atomizing inhalation, for the prevention of RDS in preterm infants.

METHODSA total of 125 preterm infants born between 28-37 weeks of gestation were randomly assigned into three groups: Intravenous and Atomizing ambroxol treatment groups (n=40 each) or Control group (n=45). The Intravenous group was injected with 15 mg/kg of ambroxol through the umbilical vein immediately after birth and then received 30 mg/kg of ambroxol daily for 2 days by intravenous drip. The Atomizing group was administered with 30 mg/kg of ambroxol daily for 2 days by atomizing inhalation immediately after birth. The Control group received no ambroxol treatment. The incidences of RDS and complications as well as the blood gas results 6 hrs after birth were compared among the three groups.

RESULTSThe incidence of RDS was 7.5%, 5.0% and 24.4% in the Intravenous, Atomizing and Control groups respectively. There were no significant differences in the incidence of RDS between the two ambroxol treatment groups. However, the incidence of RDS in the two treatment groups were noticeably lower than in the Control group (P < 0.05). The blood gas results did not show significant differences between the two ambroxol treatment groups but both groups demonstrated improved blood gas results compared with the Control group at 6 hrs after birth (P < 0.05). The incidence of complications, such as pulmonary hemorrhage, respiratory failure, intraranial hemorrhage, in the two ambroxol treatment groups was reduced compared with the Control group (P < 0.05), but there were no differences between the two ambroxol groups.

CONCLUSIONSEarly administration of either intravenous or atomizing ambroxol can produce a positive efficacy for the prevention of RDS in preterm infants. The two different ways of administration seem to result in a similar efficacy in the prevention of RDS.