Impact of resuscitation-trained healthcare workforce availability on neonatal asphyxia mortality: a population-based study

Background: Intrapartum events cause approximately 900,000 neonatal deaths annually worldwide. This study investigated whether the number of healthcare providers trained in resuscitation at the municipal level is associated with decreased neonatal mortality due to perinatal asphyxia. Methods: This population-based study analyzed neonatal deaths with birth weight ≥1500 g without congenital anomalies in São Paulo State, Brazil (2011-2020). Deaths were classified as asphyxia-associated when ICD-10 codes indicating intrauterine hypoxia, birth asphyxia, or neonatal meconium aspiration appeared on any line of death certificates. Temporal trends of neonatal mortality rate associated with perinatal asphyxia (Asphyxia-NMR) and density of Brazilian Neonatal Resuscitation Program (NRP) trained professionals per thousand live births across the 645 municipalities of the State were analyzed using Prais-Winsten regression. A multilevel mixed-effects logistic regression included three hierarchical levels (newborns, municipalities, regional health districts), adjusting for maternal age, prenatal visits, delivery mode, newborn sex, NRP-trained professional density, Gross Domestic Product (log-transformed), and year of birth. Results: Among 6,044,527 live births, 2527 neonatal deaths met inclusion criteria. Asphyxia-NMR declined from 0.43‰ (2011) to 0.31‰ (2020), an annual reduction of 3.84% (95% CI: 0.46-7.10%). The density of NRP-trained professionals rose from 1.67‰ to 35.78‰, an annual increase of 39.97% (95%CI: 24.50-57.35%). Having ≥7 trained professionals per thousand live births decreased the odds of asphyxia-associated neonatal deaths (OR 0.88; 95%CI: 0.80-0.97). Conclusion: Greater availability of healthcare professionals trained in neonatal resuscitation was independently associated with lower neonatal mortality associated with asphyxia, after adjustment for biological, economic, and regional factors.