Changes in plasma vasopressin concentration in association with coronary artery surgery or thymectomy

Plasma vasopressin concentrations in 14 patients undergoing coronary artery surgery were compared with those in eight patients undergoing thymectomy. Vasopressin concentrations increased similarly in both groups on sternotomy. A second, and more marked increase was noted in the patients requiring cardiopulmonary bypass. Haemodynamic stimuli could be responsible in both groups and might explain both the similarities and the differences between the groups.