Safety and Efficacy of Vasopressin After Fontan Completion: A Randomized Pilot Study

Abstract

Arginine vasopressin is a nonapeptide hormone with effects on intracellular water transport and arterial tone that is used in distributive shock and following cardiopulmonary bypass. We sought to evaluate the safety and efficacy of vasopressin infusion on hemodynamics and fluid balance in the early postoperative period after Fontan completion. We conducted a randomized, double-blinded, placebo-controlled study of vasopressin infusion for 24 hours after cardiopulmonary bypass for Fontan completion. Patient characteristics, hospital outcomes, and measures of hemodynamic parameters, urine output, chest tube drainage, fluid balance, laboratory data, and plasma arginine vasopressin concentrations were collected at baseline and for 48 postoperative hours. Data were analyzed using mixed-effect regressions. Twenty patients were randomized, 10 to vasopressin and 10 to placebo. Transpulmonary gradient (6.4 ± 0.5 vs 8.3 ± 0.5 mm Hg, P= .011) and chest tube drainage (23 ± 20 vs 40 ± 20 mL/kg, P= .028) for 48 hours after surgery were significantly lower in the vasopressin arm compared to placebo. Arginine vasopressin concentrations were elevated above baseline after surgery until 4 hours post cardiac intensive care unit admission in both arms, and higher in the vasopressin arm during postoperative infusion. No differences in sodium concentration, liver function, or renal function were noted between groups. Vasopressin infusion after Fontan completion appears safe and was associated with reduced transpulmonary gradient and chest tube drainage in the early postoperative period. A larger multiinstitutional study may show further outcome benefit.