Arginine vasopressin in the treatment of 50 patients with postcardiotomy vasodilatory shock

Background. The barroreflex-mediated secretion of arginine vasopressin has been found to be defective in a variety of vasodilatory shock states, such as postcardiotomy shock, and administration of the hormone markedly improve s vasomotor tone and blood pressure. The high incidence of vasodilatory sho ck in patients undergoing left ventricular assist device (LVAD) implantatio n makes this population an ideal model in which to assess the risks and ben efits of vasopressin. Methods. The medical records of the 102 patients receiving LVADs at Columbi a-Presbyterian Medical Center from January 1995 to August 1998 were reviewe d. Fifty patients were eligible for study based on a history of arginine va sopressin administration in the operating room or intensive care unit withi n 24 hours of implantation. Results. Despite LVAD implantation and the administration of vasopressors, patients were hypotensive with a mean arterial pressure less than 60 mm Hg. The administration of vasopressin (0.09 +/- 0.05 U/min) increased mean art erial pressure (58 +/- 13 to 75 +/- 14 mm Hg; p < 0.001) while reducing nor epinephrine administration (11.7 +/- 13 to 7.9 +/- 6.0 mcg/min; p = 0.023). There was no significant change in LVAD flow. The incidence of compromised regional perfusion was not different between LVAD patients who received va sopressin as compared to hemodynamically stable LVAD patients who did not r eceive vasopressin. Conclusions. We have demonstrated vasopressin at low doses to be a safe and an effective vasopressor in 50 patients with postcardiotomy vasodilatory s hock. (C) 2000 by The Society of Thoracic Surgeons.