Pre-operative neutrophil–lymphocyte ratio predicts low cardiac output in children after cardiac surgery

Abstract

AbstractNeutrophil–lymphocyte ratio has been associated with clinical outcomes in several groups of cardiac patients, including patients with coronary artery disease, cardiac failure, and cardiac transplant recipients. We hypothesised that pre- and/or post-operative haematological cell counts are associated with clinical outcomes in children undergoing cardiac surgery for CHD. We performed a post hoc analysis of data collected as part of a prospective observational cohort study (n = 83, data available n = 47) of children evaluated for glucocorticoid receptor levels after cardiac surgery (July 2015–January 2016). The association of neutrophil–lymphocyte ratio with low cardiac output syndrome, time to inotrope free, and vasoactive-inotropic score was examined using proportional odds analysis, cox regression, and linear regression models, respectively. A majority (80%) of patients were infants (median/interquartile range 4.1/0.2–7.6 months) with conotruncal (36%) and left-sided obstructed lesions (28%). Two patients required mechanical circulatory support and three died. Higher pre-operative neutrophil–lymphocyte ratio was associated with higher cumulative odds of severe/moderate versus mild low cardiac output on post-operative day 1 (odds ratio 2.86; 95% confidence interval 1.18–6.93; p = 0.02). Pre-operative neutrophil–lymphocyte ratio was not significantly associated with time to inotrope free or vasoactive-inotrope score. Post-operative neutrophil–lymphocyte ratio was also not associated with outcomes. In children after congenital heart surgery, higher pre-operative neutrophil–lymphocyte ratio was associated with a higher chance of low cardiac output in the early post-operative period. Pre-operative neutrophil–lymphocyte ratio maybe a useful prognostic marker in children undergoing congenital heart surgery.