Serum Neuronal Biomarkers in Neonates With Congenital Heart Disease Undergoing Cardiac Surgery

BACKGROUND: Newborns with congenital heart disease have associated brain damage that affects short-and long-term neurodevelopment. Several neuronal biomarkers exist that could predict brain damage. We investigated the pattern of neuron-specific enolase (NSE) and s100B levels after cardiopulmonary bypass surgery in neonates with congenital heart disease. METHODS: We completed a prospective observational study of neonates with congenital heart disease who were undergoing cardiopulmonary bypass surgery. NSE and s100B levels were measured from serum samples obtained preoperatively, immediately postoperatively, and once daily on postoperative days one to seven. Cranial ultrasounds were obtained preoperatively and postoperatively and findings were scored using an internally developed scoring system. RESULTS: Eighteen neonates were included. Immediate postoperative and peak levels of both NSE (58.0 [21.6] and 68.1 [55.7] mu g/L) and s100B (0.14 [0.3] and 0.14 [0.3] mu g/L) were significantly increased when compared with preoperative levels (34.0 [21.6] mu g/L; P < 0.01 and 0.08 [0.1] mu g/L; P < 0.02). By postoperative day seven, NSE and slOOB levels were lower than preoperative levels: NSE (18 [5.7]; P = 0.09) and s100B (0.03 [0.05]; P < 0.01). Postoperative s100B levels were negatively correlated with age at surgery and positively correlated with circulatory arrest time. Although there was no significant correlation between either NSE or s100B levels and intensive care unit length of stay, hospital length of stay, and pediatric cerebral performance category score, there was a negative correlation between postoperative levels of NSE and ventriculomegaly. CONCLUSIONS: NSE and s100B levels increase after bypass surgery and return below preoperative baseline levels by postoperative day seven. The levels of s100B were positively correlated with circulatory arrest time and negatively correlated with age at time of surgery. This finding may be supportive of pre-existing prenatal brain injury that could be enhanced by longer surgical times but also of some brain protection effect associated with longer wait until surgery.