Multicenter study of surfactant (beractant) use in the treatment of term infants with severe respiratory failure. Survanta in Term Infants Study Group.

OBJECTIVE: The purpose of this study was to determine whether surfactant (beractant) administration to term newborns in respiratory failure and at risk for requiring extracorporeal membrane oxygenation (ECMO) treatment would significantly reduce the incidence of severe complications through 28 days of age and the need for ECMO. STUDY DESIGN: A multicenter (n = 44), randomized, double-blind, placebo-controlled trial was conducted. Infants weighing 2000 gm or more with gestational ages of 36 weeks or greater were stratified by diagnosis (meconium aspiration syndrome, sepsis, or idiopathic persistent pulmonary hypertension of the newborn) and oxygenation index (15 to 22, 23 to 30, 31 to 39) and then randomly assigned to receive four doses of beractant, 100 mg/kg (n = 167), or air placebo (n = 161) before ECMO treatment and four additional doses during ECMO, if ECMO was required. The incidence of untoward effects (including hemorrhagic, neurologic, pulmonary, renal, cardiovascular, infectious, metabolic, and technical complications) occurring before and after randomization and through 28 days of age or discharge were recorded. RESULTS: The two treatment groups were comparable in baseline parameters, including birth weight, sex, gestational age, oxygenation index, and primary diagnosis. There was no difference in the incidence of severe complications. The need for ECMO therapy was significantly less in the surfactant group than in the placebo group (p = 0.038); this effect was greatest within the lowest oxygenation index stratum (15 to 22; p = 0.013). CONCLUSIONS: Use of surfactant, particularly in the early phase of respiratory failure, significantly decreases the need for ECMO in the treatment of term newborns with respiratory failure, without increasing the risk of complications.

Effect of different surfactants on pulmonary group B streptococcal infection in premature rabbits.

OBJECTIVES: To evaluate the effects of different surfactants on pulmonary infection with group B streptococci in premature rabbits and to examine the effects of different surfactants on pulmonary alveolar macrophage function of newborn rabbits. MODEL: Preterm and term rabbit pups. METHODS: Rabbit pups were infected with GBS aerosols followed by intratracheal administration of either calf lung surfactant extract, minced porcine lung surfactant (Curosurf), synthetic surfactant (Exosurf Neonatal), minced bovine lung surfactant (Survanta), human amniotic fluid-derived surfactant, rabbit surfactant, saline vehicle, or no treatment. Intrapulmonary clearance of GBS was determined by comparing bacterial counts in left lungs cultured immediately after aerosol infection with similarly infected lungs analyzed 4 hours after surfactant therapy. Phagocytosis of streptococci was ascertained by microscopic examination of the right lungs fixed in situ at 4 hours. For comparison, an in vitro method was used to measure growth of GBS in the different surfactants. RESULTS: Preterm animals had a sixfold increase in pulmonary bacterial growth compared with a slight decrease in intrapulmonary GBS in term animals when all were delivered by cesarean section (p < 0.05). In premature rabbits, GBS proliferation was lowest in animals treated with Exosurf Neonatal and highest in animals receiving Curosurf and human amniotic fluid-derived surfactant (p < 0.05). None of the surfactants promoted accelerated growth of GBS in comparison with control animals. Similar growth of GBS was seen in in vitro cultures. Intrapulmonary phagocytosis of GBS in premature pups was not altered by any of the surfactants. In term rabbit pups, the following measures of macrophage population kinetics remained normal at 1 and 24 hours after surfactant administration: viability, cell numbers based on lung lavage, and in vivo incorporation of thymidine. CONCLUSIONS: Surfactants used in clinical practice do not accelerate the in vivo growth of group B streptococci in the lungs of preterm rabbits. Some surfactants inhibit streptococcal proliferation. The effects of different surfactants are not explained by changes in macrophage function.

Comparison of three dosing procedures for administration of bovine surfactant to neonates with respiratory distress syndrome.

A multicenter, randomized, double-blind, controlled trial compared three beractant (Survanta) administration procedures in the treatment of neonatal respiratory distress syndrome. Infants weighing > or = 600 gm with respiratory distress syndrome who required assisted ventilation were treated within 8 hours of birth with beractant administered intratracheally. Procedure A required administration in two fractional doses after removal of the infant from the ventilator. Procedure B required administration in two fractional doses through a neonatal suction valve and did not require removal of the infant from the ventilator, and procedure C required administration in four fractional doses during removal from the ventilator. Procedure C is the method used in all previous beractant studies. Of the 299 infants enrolled, 103 were randomly assigned to procedure A, 100 to procedure B, and 96 to procedure C. The results indicate no significant differences among the treatment groups in the clinical outcome measures of fractional inspired oxygen, mean airway pressure, and arterial-alveolar ratio of partial pressure of oxygen at 72 hours of life, or in the incidences of air leaks, pulmonary interstitial emphysema, or death through 72 hours of life. There were no significant differences in the lowest heart rates recorded during administration of doses, but there was less oxygen desaturation during administration of dose 1 with procedure B than with procedure A (p = 0.001), and more reflux of beractant after procedure B than after procedure C (p = 0.007). We conclude that the three procedures are equally effective and can be used to administer beractant safely and effectively. Procedure B has the advantage of allowing administration without interrupting mechanical ventilation.