ROLE OF VASOPRESSIN IN THE HEMODYNAMIC-RESPONSE TO LAPAROSCOPIC CHOLECYSTECTOMY

We studied 10 patients undergoing laparoscopic cholecystectomy (group 1) and five control patients (group 2). We measured heart rate, arteri al pressure, right atrial pressure (RAP), cardiac index (CI), systemic vascular resistance index (SVRI), intrathoracic pressure (ITP), plasm a osmolality, adrenaline, noradrenaline and arginine vasopressin (aVP) concentrations, and serum renin activity (SRA), and calculated the at rial transmural pressure gradient (ATPG). We recorded significant decr eases in mean arterial pressure (MAP), SVRI and CI in both groups (P<0 .05) after induction of anaesthesia. MAP and SVRI increased (P<0.01) w hile CI decreased further in group 1 patients during the pneumoperiton eum. In group 1 plasma aVP concentration increased after insufflation of the pneumoperitoneum to a level sufficient to cause the recorded ha emodynamic changes. ATPG decreased in group 1 patients during the pneu moperitoneum, and this is a recognized trigger for aVP release.