Interrelations of intraoperative changes in cerebral tissue oxygen saturation on brain volumes and neuro-development outcome after the comprehensive stage II procedure in infants with hypoplastic left heart syndrome

Abstract Objectives : The monitoring of cerebral tissue oxygen saturation by near-infrared spectroscopy (ScerebO2) is widely used in pediatric cardiac anesthesia. However, little information is available on the effects of changes in perioperative ScerebO2 on brain morphology and neurological outcome. The primary hypothesis tested in this study was that intraoperative ScerebO2 during the comprehensive stage II procedure correlates with brain volumes assessed by magnetic resonance imaging and neurodevelopemental scores. Design : Retrospective observational cohort study Setting : University Hospital, Pediatric Heart Centre Patients and Measurements : In 19 infants, the intraoperative course of ScerebO2 during the comprehensive Phase II procedure was examined. Minimal ScerebO2 and integrated ScerebO2 below 45% (AUC) during surgery as well as cerebral MRI examinations and Bayley III test at the age of 2 to 3 years were analyzed. Main Results : A positive correlation between minimal ScerebO2 and intracranial volume (p = 0.0243), total brain volume (p = 0.0243) and white matter volume (p = 0.0276) was observed, as was a negative correlation between AUC and intracranial volume (p = 0.0454) and white matter volume (p = 0.0381), respectively. No association was found between ScerebO2 and Bayley-III Score. Conclusion : The correlation between ScerebO2 and brain volumes measured by MRI points out a possible importance of neuroprotective strategies aimed at optimizing ScerebO2 during complex congenital heart surgery. That no correlation between ScerebO2 and Bayley III Score was found suggests the multifactorial causes for neurological outcome in children with congenital heart defects.