Arginine Vasopressin Therapy of Vasodilatory Shock after Cardiac Surgery

Ahn, Young Chan; Park, Kook Yang; Park, Chul Hyun; Kim, Gun Woo; Lee, Jae Ik; Jun, Yang Bin; Choi, Chang Hyu; Hyun, Sung Youl

Abstract

BACKGROUND: Vasodilatory shock has been implicated in life-threatening complications after open heart surgery, where the systemic inflammatory reaction is attributed to the cardiopulmonary bypass (CPB). The secretion of arginine vasopressin (AVP) has been found to be defective in a variety of vasodilatory shock states and administration of AVP markedly improves vasomotor tone and blood pressure. So we reviewed our experience of AVP therapy in patients with vasodilatory shock following heart surgery using CPB. MATERIAL AND METHOD: From January 2004 to July 2006, we reviewed the records of patients who received AVP therapy for vasodilatory shock following heart surgery using CPB. Vasodilatory shock was defined as a mean arterial pressure lower (MAP) than 70 mmHg, a cardiac index greater than 2.5 L/min/m2, peripheral vascular resistance lower than 800 dyn/s/cm5, and vasopressor requirements. The hemodynamic responses of patients who received AVP therapy for vasodilatory shock after cardiac surgery were analyzed retrospectively. RESULT: One hundred ninety nine open cardiac surgery patients were consecutively included in this study. Twenty two patients (11.1%) met criteria for vasodilatory shock. Despite the administration of high dose catecholamine vasopressor, all patients were hypotensive with a mean arterial pressure less than 70 mmHg. AVP therapy increased MAP from 53.3+/-7.4 to 82.0+/-12.0 mmHg at 1 hour (p <0.001) and decreased other vasopressor requirements from 25+/-7 to 18+/-6 at 1 hour (p <0.001) and individually maintained it for 12 hours.
CONCLUSION
Our date suggest that AVP may be a safe and an effective vasopressor in patients with vasodilatory shock. In patients exhibiting vasodilatory shock after heart surgery, replacement of AVP increases blood pressure and reduces catecholamine vasopressor requirements.