[Analgesic and neuroendocrinal response in heart surgery: II. Adreno-medullary response]

In fifty-five patients who had undergone open-heart surgery, plasma levels of catecholamines and urinary excretion of adrenalin and noradrenalin were studied. We have divided the patients in three groups, according to the analgesic administered during the operation: group A, patients anesthesized with Pentazocina; group B, with Morfine; group C with Fentanest. By determining these catecholamate levels, we have been able to show an increase in sympathetic activity in all three groups. However, during the peroperative period. Fentanest gave the smallest increase and Pentazocina the largest. The more prolonged analgesia of Morfine manifested itself during the post-operative period in a smaller elimination of adrenalin. We then studied the influence of Fentathinil on the sympatho adreno-medullar system. This recently-acquired analgesic, used in extracorporeal perfusion, grave a catecholamine elimination inferior to that found with Fentanest.