Coupling between Regional Oxygen Saturation of the Brain and Vital Signs during Immediate Transition after Birth

Abstract

Introduction: The primary aim was to analyze any coupling of heart rate (HR)/arterial oxygen saturation (SpO₂) and regional cerebral oxygen saturation (rScO₂) and regional cerebral fractional tissue oxygen extraction (cFTOE) during immediate transition after birth in term and preterm neonates to gain more insight into interactions. Methods: The present study is a post hoc analysis of data from 106 neonates, obtained from a prospective, observational study. Measurements of HR, SpO₂, rScO₂, and cFTOE were performed during the first 15 min after birth. The linear and nonlinear correlation were computed between these parameters in a sliding window. The resulting coupling curves were clustered. After clustering, demographic data of the clusters were de-blinded and compared. Results: Due to missing data, 58 out of 106 eligible patients were excluded. Two clusters were obtained: cluster 1 (N = 39) and cluster 2 (N = 9). SpO₂ had linear and nonlinear correlations with rScO₂ and cFTOE, whereby the correlations with rScO₂ were more pronounced in cluster 2. HR-rScO₂ and HR-cFTOE demonstrated a nonlinear correlation in both clusters, again being more pronounced in cluster 2, whereby linear correlations were mainly absent. After de-blinding, the demographic data revealed that the neonates in cluster 2 had significantly lower gestational age (mainly preterm) compared to cluster 1 (mainly term). Discussion: Besides SpO₂, also HR demonstrated a nonlinear correlation with rScO₂ and cFTOE in term and preterm neonates during immediate transition after birth. In addition, the coupling of SpO₂ and HR with cerebral oxygenation was more pronounced in neonates with a lower gestational age.