Predicting Surfactant Need at Birth: Failed Validation of a Bedside Method Using Gastric Aspirates

To validate a prototype point-of-care (POC) test for the lecithin/sphingomyelin (L/S) ratio by identifying the optimal L/S cut-off for predicting surfactant need in preterm infants < 30 weeks' gestation using gastric aspirates (GAS) sampled at birth and to assess clinical feasibility.

GAS was sampled within 45 min of birth and analysed using the only available prototype POC L/S test. The primary outcome was the optimal L/S cut-off and diagnostic accuracy in predicting rescue surfactant treatment per European RDS guidelines, assessed by receiver operating characteristics. L/S results were blinded to clinicians. Due to a dispute between clinical investigators and patent holders, legal restrictions prohibit reporting of the primary outcome.

Of 93 eligible infants, 25 were not included: Six cases (6%) had no GAS available, 12 infants (13%) received surfactant before sampling and 7 (8%) other reasons. Of 68 included, 42 (62%) received surfactant, and 40% were treated within 2 h of life (median: 147 min [IQR: 89; 327]).

We aimed to validate a POC L/S test but are legally restricted from disclosing results. Clinical applicability seems limited, as a substantial proportion of infants had no GAS available or required surfactant before sampling. The potential to accelerate treatment appears limited.