Surfactant therapy in neonates with respiratory failure due to haemorrhagic pulmonary oedema

We studied the clinical and biochemical factors associated with surfactant dysfunction and factors affecting the responsiveness to exogenous surfactant among 27 neonates with haemorrhagic pulmonary oedema (HPE). HPE was defined as the presence of a large amount of blood-stained lung effluent and respiratory failure which was difficult to differentiate from respiratory distress syndrome. Among the neonates, 33% had very low birth weight, 96% were preterm, 70% were delivered by caesarean section, and 44% had delivery room intubation. The onset of HPE was at 1.5±0.1 h (mean ± SEM) after birth. In 26 cases, surfactant was administered at 3.0±1.3 h after the onset of HPE. The concentrations of surfactant protein A (SP-A), disaturated phosphatidylcholine (DSPC), and albumin in the epithelial lining fluid were determined using the first lung effluent from the patients. The level of inhibitory activity against pulmonary surfactant in the effluent was determined in vitro. Surfactant inhibitory activity was associated with lower birth weight, earlier gestational age, delivery room intubation, earlier onset of HPE, and lower SP-A or DSPC concentration. A good response to exogenous surfactant, which was defined as ventilatory index <0.047 at 1 h after surfactant administration, was seen in 82% of cases, and was associated with lower serum albumin, lower birth weight, and earlier gestational age. Cases with higher DSPC concentration prior to surfactant administration and shorter interval between the onset of HPE and surfactant administration showed an immediate response to surfactant, followed by no increase in ventilatory index for 24 h after surfactant administration. Conclusion: exogenous surfactant appeared to be a useful adjunctive therapy for overcoming surfactant inhibition and normalising the respiratory status of infants with haemorraghic pulmonary oedema. Surfactant treatment for this indication awaits further investigations including a randomised controlled study.Abbreviations ALB albumin - AS airway specimen - DSPC disaturated phosphatidylcholine - ELF epithelial lining fluid - HPE haemorrhagic pulmonary oedema - In natural logarithm - RDS respiratory distress syndrome - SP-A surfactant protein A - VI ventilatory index - _min minimum surface tension