Comparison of clinical responses to natural and synthetic surfactants

The clinical responses to both natural and synthetic surfactants were observed in two District General Hospital Neonatal Units who were centrally randomised as part of two separate multicentre trials (OSIRIS and Curosurf 4). Forty five infants were enrolled consecutively in the OSIRIS trial using synthetic surfactant (Exosurf), while 21 infants were subsequently enrolled in the Curosurf 4 trial using natural surfactant (Curosurf). There were no significant differences between the groups for mean birth weight, gestational age, inspired oxygen (FiO2), or arterial: alveolar oxygen ratio (a/A) prior to surfactant administration. Oxygen requirements fell significantly more rapidly within the first 24 hours for patients treated with Curosurf compared to Exosurf (p < 0.001). Mean duration of > 40% oxygen requirement was significantly shorter in the Curosurf group (2.6 days) compared to 8.0 days in the Exosurf group (p < 0.01). Mean duration of oxygen therapy was also significantly shorter in the Curosurf group (10.2 days) compared to 17.1 days in the Exosurf group (p < 0.05). Ten infants (24%) in the Exosurf group developed intraventricular haemorrhage (IVH) compared to none in the Curosurf group (p < 0.05). As oxygen requirements appear to decrease more rapidly following administration of Curosurf compared to Exosurf a large prospective randomized multicentre trial needs to be performed to compare the effects of these surfactants on both short and long-term outcome.