Activation of kynurenine pathway of tryptophan metabolism after infant cardiac surgery with cardiopulmonary bypass: a prospective cohort study

Background: Serum kynurenic acid is associated with poor outcomes after infant cardiopulmonary bypass (CPB), but comprehensive mapping of the kynurenine pathway (KP) after CPB has yet to be performed. Aims: To map changes in the KP induced by infant CPB. Methods: Compared changes in serum KP metabolites through 48hrs post-op with liquid-chromatography-tandem mass spectrometry. Results: Infant CPB results in marked increase in proximal, but not distal metabolites of the KP. Conclusions: Infant CPB leads to accumulation of circulating KP metabolites, which have important neurologic and immunologic activities. Thus, further exploration of the KP is warranted in these high-risk infants.