Cerebral regional oxygen saturation variability in neonates following cardiac surgery

BACKGROUND: Reduced cerebral regional oxygen saturation (crSO(2)) variability in neonates, as measured by near-infrared spectroscopy, following cardiac surgery with deep hypothermic circulatory arrest (DHCA) is associated with poor neurodevelopmental outcomes. We sought to evaluate the variability of crSO(2) in a cohort of neonates following cardiac surgery with brief or no exposure to DHCA. METHODS: Variability of averaged 1-min crSO(2) values was calculated for the first 48 h following cardiac surgery in consecutive neonates over a 30-month period. Neonates requiring aortic arch repair underwent antegrade cerebral perfusion with either brief or no exposure to DHCA. RESULTS: There were 115 neonates included in the study. Reduced crSO(2) variability was observed in neonates with aortic arch obstruction (p = 0.02) and non-survivors (p = 0.02). Post hoc analysis demonstrated that the reduction in crSO(2) variability was not as marked as in previously studied neonates with aortic arch obstruction who received DHCA alone (p < 0.001). CONCLUSIONS: Neonates with aortic arch obstruction have reduced crSO(2) variability following cardiac surgery. The reduction in crSO(2) variability observed in aortic arch obstruction is likely influenced by a number of factors, including perioperative perfusion technique. The impact of interventions on crSO(2) variability and resultant influence on neurodevelopmental outcomes requires further study. IMPACT: Neonates with aortic arch obstruction have reduced crSO(2) variability following cardiac surgery, which has been associated with poor neurodevelopmental outcomes, and is likely influenced by a number of factors, including perioperative perfusion technique. The contribution of perioperative perfusion technique to crSO(2) variability following neonatal cardiac surgery is significant. Monitoring of crSO(2) variability may provide insights into the adequacy of cerebral perfusion in neonates following cardiac surgery.