Cardiopulmonary-Bypass Glial Fibrillary Acidic Protein Correlates With Neurocognitive Skills

Background: Neurocognitive deficits at school starting age may affect as many as 50% of children who underwent cardiac surgery for complex congenital heart disease (CHD). The aim of this study was to identify which phases of cardiopulmonary bypass (CPB) are associated with an increased risk of impaired neurodevelopmental skills in children with complex CHD. This was assessed by means of glial fibrillary acidic protein (GFAP) plasma levels during CPB for CHD surgery, as a marker of neurologic insult. We correlated GFAP levels with clinical parameters and neurodevelopmental outcome. Methods: We studied 45 children undergoing surgery for complex CHD. We measured plasma GFAP levels by enzyme-linked immunosorbent assay at the following steps: anesthesia induction, CPB start, end of hypothermia, end of rewarming, and end of CPB. Neurologic assessment and Vineland Adaptive Behavior Scales (VABS-I) were administered to patients at least 18 months after surgery. Results: GFAP was undetectable before surgery and it peaked at the end of hypothermia or rewarming. Multiple regression analyses showed that GFAP peak level and preoperative neurologic comorbidity were significant independent predictors of neurologic impairment, as showed by VABS-I communication domain intelligence quotient (IQ). Receiver operating characteristic curve showed that the model was highly significant. Conclusions: Impaired neurodevelopment was associated with increase of GFAP plasma levels during cardiac surgery in infants. The identification of the neurologic high-risk phases of CPB run could support the application of new neuroprotective strategies for CHD repair.