Differences in Management of Neonates with Hypoxic–Ischemic Encephalopathy (HIE) by Level of Neonatal Care Provided at Birth: Insights from a Referral-Based Cohort in the Canton of Zurich, Switzerland

<b>Background/Objectives</b>: Neonates with hypoxic-ischemic encephalopathy (HIE) are born in delivery facilities with different levels of neonatal care. The objective of this study was to investigate differences in the incidence of HIE and postnatal management between different levels of neonatal care in delivery facilities. <b>Methods</b>: This is a retrospective, multi-center cohort study of neonates with moderate-to-severe HIE receiving therapeutic hypothermia (TH) in the Canton of Zurich, Switzerland, registered in the Swiss National Asphyxia and Cooling Register between 2015 and 2023. Incidences of HIE receiving TH were calculated for all delivery facilities according to the national levels of neonatal care on site (Level I-basic; Level IIB-intermediate (no Level IIA facility in the Canton of Zurich); Level III-intensive neonatal care). Perinatal characteristics and variables on transport and outcomes were compared between neonates born in Level I and Level IIB facilities (the majority of the HIE population) and reported for neonates born in all other facilities (for completeness). <b>Results</b>: A total of 173 neonates (79 (45.7%) born in Level I; 80 (46.2%) in Level IIB; 9 (5.2%) in Level III; 5 (2.9%) in birthing centers) were admitted to a neonatal cooling center to receive TH. The average number of annual cases of HIE receiving TH per facility was 0.67 (0.11-1.50) in Level I and 2.22 (0.22-3.11) in Level IIB facilities (<i>p</i> = 0.088), respectively. There was no difference in Apgar score, worst pH (within 60 min after birth) and the severity of encephalopathy between neonates born in Level I and Level IIB facilities. Neonatal transport team requests were initiated earlier in Level I facilities (median 12 vs. 34 min of life, <i>p</i> < 0.001). There was no difference in age at initiation of TH (median 3 vs. 3 h, <i>p</i> = 0.431) and the time when target temperature was reached (median 4 vs. 4 h, <i>p</i> = 0.431) between neonates born in Level I and Level IIB facilities. <b>Conclusions</b>: The level of neonatal care available in delivery facilities influenced the management of neonates with HIE receiving TH.