Oral or Poster Presentation
Concurrent Session 4B - Neo Cardiovascular Science & Hemodynamics
Introduction: The goal of this study was to assess cerebral hemodynamics and oxygen metabolism alterations during the preoperative and postoperative period in neonates with dextro-transposition of the great arteries (TGA) by comparing with age-matched healthy controls and investigate their association with 4-months motor development outcome.
Methods: In 24 neonates undergoing arterial switch operation and 24 age-matched healthy controls (Table1), we used an advanced bedside optical monitoring technique that combined frequency-domain near-infrared spectroscopy (FDNIRS) and diffuse correlation spectroscopy (DCS) to assess cerebral oxygen saturation (SO2), oxygen extraction fraction (OEF), cerebral blood volume (CBV) and indices of cerebral blood flow (CBFi) and cerebral oxygen metabolism (CMRO2i). Concurrently, peripheral arterial oxygen saturation (SaO2) and hemoglobin concentration in the blood (HGB) were extracted from clinical charts. Optical measures were compared between three (preoperative, postoperative unstable and postoperative stable) periods in TGA neonates and with healthy controls. Association between postnatal cerebral findings and motor development at 4-months were assessed to identify low-risk and high-risk motor outcome in infants.
Results: Comparing the preoperative measures with healthy controls helped identify abnormal patterns such as significantly decreased SaO2 and increased HGB reflecting hypoxia, decreased OEF, CMRO2i and CBV indicating delayed brain maturation, unchanged CBFi suggesting postnatal blood flow preservation (Table2). Postoperatively, hemodynamic and metabolic recovery was demonstrated with an increase in SaO2, OEF, and CMRO2i reaching the level of healthy neonates during stable period (Table3). Compared to low-risk infants, high-risk infants presented significantly higher HGB during preoperative period, lower SO2, lower HGB and higher OEF during postoperative unstable period (Table4).
Conclusion: Continuous monitoring of the postnatal cerebral hemodynamics and oxygen metabolism measures in TGA neonates using bedside FDNIRS-DCS and comparison with age-matched controls helped assess the abnormal patterns of the postnatal cerebral measures. Their association with 4-months motor outcome seems promising in identifying critical window of brain vulnerability in TGA neonates.