ObjectiveTo study the efficacy of pulmonary surfactants (PS) combined with continuous distending pressure (CDP) for treatment of respiratory distress syndrome (RDS) in very low birth weight (VLBW) infants.MethodsNinety VLBW infants with RDS (weight <1 500 g, gestational age <34 weeks) were randomly treated with a combination of PS and the Infant Flow Advance system which can provide CDP, PS alone or the Infant Flow Advance system alone (n=30 in each group). Clinical symptoms, signs, and blood gas changes were assessed 1, 6, 12 and 24 hrs after treatment. The treatment outcomes were compared between the three groups.ResultsClinical symptoms and signs, as well as the values of PaO2, PaCO2 and pH, in the three groups were improved 1, 6, 12 and 24 hrs after treatment. The combined use of PS with CDP produced a higher PaO2 and a lower PaCO2 compared with the PS or CDP use alone (P＜0.01). The combination treatment group had shorter duration of oxygen therapy and shorter length of hospital stay than the PS or CDP use alone group. ConclusionsThe combined use of PS with CDP can effectively improve pulmonary oxygenation and ventilation and shorten the duration of oxygen therapy and the length of hospital stay in VLBW infants with RDS.