An unusual cause of persisting hyperlactatemia in a neonate undergoing open heart surgery.

Being a reflection of the degree of global tissue anoxia, serum lactate levels therefore can be used as a marker of organ damage and eventual outcome. A statistically significant association was observed between serum lactate levels and subsequent mortality and morbidity in critically ill adults, children, and neonates. In cardiac critical care, hyperlactatemia is usually multifactorial in origin, resulting from a combination of etiologies. Many centers are using serial lactate levels in conjugation with other parameters of cellular oxygen delivery, consumption, or extraction to monitor prognosis after pediatric cardiac surgery. A single initial lactate level has a lesser predictive value for morbidity and mortality after pediatric cardiac surgery than its failure to fall within 48 hours of surgery. In case of persistently high lactate levels with no other evidence of cellular hypoperfusion, other possibilities must be considered. There has been an established association of lactic acidosis with thiamine deficiency, but this has not yet been reported in newborns undergoing congenital cardiac surgery. We present one such rare case.