Cerebral oxygen saturation does not normalize until after stage 2 single ventricle palliation

Area of Science:

• Pediatric Cardiology
• Congenital Heart Disease
• Cerebral Physiology

Background:

• Optimizing neurologic outcomes in single ventricle congenital heart disease (SV-CHD) necessitates monitoring cerebral oxygen saturation (SCO2).
• The relationship between SCO2 and the stage of palliative care in SV-CHD requires further investigation.

Purpose of the Study:

• To investigate the correlation between cerebral oxygen saturation (SCO2) and the specific stage of palliative surgery in pediatric patients with single ventricle congenital heart disease.
• To determine if SCO2 levels can predict perioperative mortality in this vulnerable population.

Main Methods:

• Continuous intraoperative cerebral oxygen saturation (SCO2) monitoring was performed in 34 infants and children undergoing palliative surgery for SV-CHD.
• A control group of 12 neonates with ductus-dependent circulation undergoing complete repair was also studied.
• SCO2 data were correlated with the patient's palliative stage and clinical outcomes, including perioperative mortality.

Main Results:

• Baseline SCO2 varied significantly across palliative stages, being lowest (41%) in infants undergoing interstage operations.
• Post-bypass, SCO2 improved in stage 2 palliation infants (53%), but decreased significantly by the end of surgery in neonates (48%).
• Cerebral oxygen saturation at the conclusion of surgery was significantly lower in patients who died (38%) compared to survivors (61%).

Conclusions:

• In children with single ventricle physiology, SCO2 demonstrates a dynamic pattern, decreasing after initial palliation and remaining low before second-stage palliation.
• SCO2 levels normalize before and after the Fontan procedure.
• Low postoperative cerebral oxygen saturation is a significant predictor of perioperative mortality and has implications for neurologic injury and interim mortality.