Cerebral Oxygenation Pattern during Therapeutic Hypothermia after Perinatal Asphyxia: A Single Center Cohort Study

Abstract

Introduction: Investigation the association between cerebral oxygenation and short-term adverse outcome in asphyxiated infants with hypoxic-ischemic encephalopathy (HIE) during therapeutic hypothermia (TH). Methods: Near infrared spectroscopic-derived cerebral oxygen saturation (rScO2) pattern during first 4 days was compared to early brain MRI (4–10 days) using the Weeke score to define MRI-derived brain injury of infants with GA >35 weeks treated with TH within 6 h between 2010 and 2023. Weeke scores of >9 were considered adverse short-term outcome. Infants with congenital abnormalities, chromosomal disorders, or on ECMO were excluded. Results: 292 infants (mean ± 1 SD: GA 39.4 ± 1.9 weeks; BW 3, 442 ± 621 g; median [IQR] 5-min Apgar score 4 [3]) were eligible. According to the Sarnat staging, HIE was mild, moderate, or severe in 77, 148, and 67 infants. Adverse short-term outcome/death occurred in 0, 39 (26.4%), and 67 (100%) infants in mild, moderate, and severe HIE groups. Severe HIE infants had higher rScO2 values compared to moderate or mild HIE infants. Mixed model analysis showed an association between rScO2 (dependent variable), time after birth, adverse short-term outcome, and inhaled nitric oxide. Logistic regression showed that adverse outcome had a positive association with rScO2 and first lactate levels. Discussion: High cerebral oxygen saturation during TH is associated with adverse short-term outcome. This knowledge may contribute to early counseling and decision-making. Combination with early blood lactate levels strengthened this association. Simultaneous NO-ventilation may confound this association.