Abstract
BACKGROUND
Assessment of hemodynamics during the transitional period in preterm infants is challenging.
OBJECTIVES
We aimed to describe the relationship between cerebral regional tissue oxygenation saturation (CrSO2), preductal perfusion index (PI), echocardiographic and clinical parameters in extremely preterm infants in their first 72 hours of life.
DESIGN/METHODS
This single center prospective observational study was conducted in the level 3 neonatal intensive care unit of Sainte-Justine Hospital between July 2015 and May 2016. Twenty newborns born at <28 weeks of gestation were continuously monitored with CrSO2 and preductal PI as well as cardiac outputs measured at 6, 24, 48 and 72 hours of life. Data were assessed for normality and Pearson correlation statistics were performed. Serial data were tested using a one-way ANOVA with repeated measures and Bonferroni adjustment. The level of significance was set to 0.05
RESULTS
Median gestational age and birth weight were 25.0 weeks (24–26) and 750 g (655–920) respectively. Table 1 describes the measures over the 72 hours of the study period. CrSO2 and preductal PI were weakly correlated with mean blood pressure, PaCO2, lactates and haemoglobin. Fifteen patients had at least one episode of low left and/or right ventricular output (RVO) measured and showed strong correlation between CrSO2 and superior vena cava (SVC) flow at H6 (r=0.74) and H24 (r=0.86) and between PI and RVO at H6 (r=0.68) and H24 (r=0.92). Five patients had low SVC flowat H6 and showed strong correlation between PI and RVO (r=0.98).
CONCLUSION
CrSO2 and preductal PI were weakly correlated with clinical parameters in the preterm infants. However, CrSO2 and PI showed stronger correlation with RVO and SVC flow during low cardiac output states.

