Change in neonatal resuscitation guidelines and trends in incidence of meconium aspiration syndrome in California.

To describe trends in the incidence and severity of meconium aspiration syndrome (MAS) around the release of revised Neonatal Resuscitation Program (NRP) guidelines in 2016. The California Perinatal Quality Care Collaborative database was queried for years 2013-2017 to describe the incidence and outcomes of infants with MAS. Results were analyzed based on both individual years and pre- vs. post-guideline epochs (2013-15 vs. 2017). Incidence of MAS decreased significantly from 2013-15 to 2017 (1.02 to 0.78/1000 births, p < 0.001). Among infants with MAS, delivery room intubations decreased from 2013-15 to 2017 (44.3 vs. 35.1%; p = 0.005), but similar proportion of infants required invasive respiratory support (80.1 vs. 80.8%), inhaled nitric oxide (28.8 vs. 28.4%) or extracorporeal membrane oxygenation (0.81 vs. 0.35%). While the study design precludes confirmation of implementation of the recent NRP recommendation, there was no increase in the incidence or severity of MAS following its release.