PLASMA NEUROPEPTIDE-Y AND CATECHOLAMINES IN PEDIATRIC-PATIENTS UNDERGOING CARDIAC OPERATIONS

Objective: Our objective was to assess the sympathoadrenal response in pediatric patients undergoing repair of congenital cardiac defects. M ethods: plasma catecholamine (norepinephrine and epinephrine) and neur opeptide Y concentrations were quantified before and after cardiopulmo nary bypass to assess the response to cardiopulmonary bypass, To deter mine the response to aortic occlusion, levels of plasma catecholamines and neuropeptide Y were measured at the time of and immediately after release of the aortic crossclamp, Results: During cardiopulmonary byp ass, no significant change in levels of plasma norepinephrine (n = 43) , epinephrine (n = 37), or neuropeptide Y (n = 46) was observed, Aorti c occlusion induced a significant increase in plasma neuropeptide Y, b ut not in catecholamines. There was a greater increase in plasma neuro peptide Y in children older than age I year than in those younger than I year, Conclusions: Plasma neuropeptide Y may be a useful marker of sympathetic nervous system activity, Children younger than age 1 year showed a lesser sympathetic response compared with the response in old er children.