Post cardiac surgery vasoplegia is associated with high preoperative copeptin plasma concentration.

Overview & Synopsis

ABSTRACT: INTRODUCTION: Post cardiac surgery vasodilatation is possibly related to a vasopressin deficiency that could be related to a chronic stimulation of the adeno-hypophysis. To assess vasopressin system activation, perioperative course of copeptin and vasopressin plasma concentrations have been studied in consecutive patients operated on cardiac surgery. METHODS: 64 consecutive patients scheduled for elective cardiac surgery with cardiopulmonary bypass were studied. Haemodynamic, laboratory and clinical data were recorded before and during cardiopulmonary bypass, and at the 8th post-operative hour (H8). At the same time, point's blood was withdrawn to determine plasma concentrations of arginine-vasopressin (AVP, radioimmunoassay) and copeptin (immunoluminometric assay). Post cardiac surgery vasodilation (PCSV) was defined as a mean arterial blood pressure less than 60 mmHg with a cardiac index [equal to or greater than] 2.2 L * min^-1 * m^-2, and was treated with norepinephrine (NE) in order to restore a mean blood pressure > 60 mmHg. Patients with PCSV were compared to the other patients (controls). Student's t, Fisher's exact test, or non parametric tests (Mann Whitney, Wilkoxon) were used when appropriate. A correlation between AVP and copeptin has been evaluated and a receiver-operator characteristic (ROC) analysis was calculated to assess the utility of preoperative copeptin to distinguish between controls and PCSV patients. RESULTS: Patients who experienced a PCSV have significantly higher copeptin plasma concentration before cardiopulmonary bypass (P