Late surfactant replacement therapy increases surfactant protein-B content in a randomized pilot study.

Department of Pediatrics, University of California San Francisco, San Francisco CA.
Pediatric Research (Impact Factor: 2.84). 10/2012; 72(6). DOI: 10.1038/pr.2012.136
Source: PubMed

ABSTRACT Background:Surfactant dysfunction may contribute to the development of bronchopulmonary dysplasia in persistently ventilated preterm infants. We conducted a multicenter randomized, blinded pilot study to assess the safety and efficacy of late doses of a surfactant protein-B (SP-B) containing surfactant (calfactant) in combination with prolonged inhaled nitric oxide (iNO) in infants ≤ 1000g birth weight.Methods:We randomized 85 preterm infants ventilated at 7-14 d to late surfactant (up to 5 doses) and prolonged iNO versus iNO-alone. Large aggregate surfactant was isolated from daily tracheal aspirates for measurement of SP-B content, total protein and phospholipid.Results:Late surfactant was administered with minimal acute adverse effects. Clinical status and tracheal aspirate surfactant recovery and SP-B content were transiently improved compared to Controls; effects waned after 1 day. The change in SP-B content with surfactant dosing was positively correlated with SP-B levels during treatment (r=0.50, P=0.02).Conclusion:Low SP-B content increased with calfactant administration, but the relationship of response to SP-B levels suggests degradation as a contributing mechanism for SP-B deficiency and surfactant dysfunction. We conclude that late surfactant therapy in combination with iNO is safe and transiently increases surfactant SP-B content, which may lead to improved short- and long-term respiratory outcomes.Pediatric Research (2012); doi:10.1038/pr.2012.136.

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