RESUMO
Plasma and urinary catecholamine concentrations have been measured in 13 patients undergoing cardiac surgery involving cardiopulmonary bypass. The large and progressive increase in plasma catecholamines during bypass reported in previous studies has not been confirmed, and this may be a result of improvements in surgical, anaesthetic and perfusion techniques. The interpretation of urinary findings was complicated by the finding of a positive correlation between catecholamine excretion and urine flow-rate. The findings suggest the need to modify current concepts of the adrenergic response to cardiac surgery and bypass, and question the validity of measuring the urinary catecholamine concentration as an index of stress in these circumstances.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Catecolaminas/metabolismo , Circulação Extracorpórea , Adulto , Idoso , Anestesia Geral , Catecolaminas/sangue , Catecolaminas/urina , Criança , Ensaios Clínicos como Assunto , Feminino , Halotano , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nitroso , Pancurônio , Estresse Fisiológico/metabolismo , Tiopental , Fatores de Tempo , TubocurarinaRESUMO
12 out of 13 patients who underwent cardiac surgery requiring extracorporeal circulation survived the operation. Arterial and venous catecholamines were measured throughout the operation. Larges rises in catecholamine levels were not seen although significant changes did occur in arteriovenous differences and also between samples at certain points in the operation. These facts do not agree with Lillehei's findings (3) and may reflect improvements in surgical technique, anaesthesia and the reduced time on bypass. However the lack of an overall measurable adrenergic response in terms of plasma catecholamine levels does agree with similar findings after open heart surgery (4) and during other surgical procedures (5).
