Abnormalities in cerebral hemodynamics and changes with surgical intervention in neonates with congenital heart disease

Objective: To use novel optical techniques to measure perioperative cerebral hemodynamics of diverse congenital heart disease (CHD) groups (two-ventricle, d-transposition of the great arteries [TGA], and single ventricle [SV]) and (1) compare CHD groups with healthy controls preoperatively and (2) compare preoperative and postoperative values within each CHD group.

Methods: Frequency-domain near-infrared spectroscopy and diffuse correlation spectroscopy were used to measure cerebral oxygen saturation, cerebral blood volume, cerebral blood flow index, cerebral oxygen extraction fraction (OEF, calculated using arterial oxygen saturation and cerebral oxygen saturation), and an index of cerebral metabolic rate of oxygen consumption in control and CHD neonates. Preoperative CHD measures were compared with controls. Preoperative and postoperative measures were compared within each CHD group.

Results: In total, 31 CHD neonates (7 two-ventricle, 11 TGA, 13 SV) and 13 controls were included. Only neonates with SV CHD displayed significantly lower preoperative cerebral blood flow index (P < .04) than controls. TGA and SV groups displayed greater OEF (P < .05) during the preoperative period compared with controls. Compared with the preoperative state, postoperative neonates with TGA had a greater arterial oxygen saturation with lower OEF.

Conclusions: Differences in cerebral hemodynamics and oxygen metabolism were observed in diverse CHD groups compared with controls. Increased OEF appears to be a compensatory mechanism in neonates with TGA and SV. Studies are needed to understand the relationship of these metrics to outcome and their potential to guide interventions to improve outcome.