Acute Hemodynamics in the Fontan Circulation: Open-Label Study of Vasopressin*

Abstract

Objective: To describe the acute hemodynamic effect of vasopressin on the Fontan circulation, including systemic and pulmonary pressures and resistances, left atrial pressure, and cardiac index. Design: Prospective, open-label, nonrandomized study (NCT04463394). Setting: Cardiac catheterization laboratory at Lucile Packard Children’s Hospital, Stanford. Patients: Patients 3–50 years old with a Fontan circulation who were referred to the cardiac catheterization laboratory for hemodynamic assessment and/or intervention. Interventions: A 0.03 U/kg IV (maximum dose 1 unit) bolus of vasopressin was administered over 5 minutes, followed by a maintenance infusion of 0.3 mU/kg/min (maximum dose 0.03 U/min). MEASUREMENTS AND MAIN RESULTS: Comprehensive cardiac catheterization measurements before and after vasopressin administration. Measurements included pulmonary artery, atrial, and systemic arterial pressures, oxygen saturations, and systemic and pulmonary flows and resistances. There were 28 patients studied. Median age was 13.5 (9.1, 17) years, and 16 (57%) patients had a single or dominant right ventricle. Following vasopressin administration, systolic blood pressure and systemic vascular resistance (SVR) increased by 17.5 (13.0, 22.8) mm Hg (Z value −4.6, p < 0.001) and 3.8 (1.8, 7.5) Wood Units (Z value −4.6, p < 0.001), respectively. The pulmonary vascular resistance (PVR) decreased by 0.4 ± 0.4 WU (t statistic 6.2, p < 0.001), and the left atrial pressure increased by 1.0 (0.0, 2.0) mm Hg (Z value −3.5, p < 0.001). The PVR:SVR decreased by 0.04 ± 0.03 (t statistic 8.1, p < 0.001). Neither the pulmonary artery pressure (median difference 0.0 [−1.0, 1.0], Z value −0.4, p = 0.69) nor cardiac index (0.1 ± 0.3, t statistic −1.4, p = 0.18) changed significantly. There were no adverse events. Conclusions: In Fontan patients undergoing cardiac catheterization, vasopressin administration resulted in a significant increase in systolic blood pressure, SVR, and left atrial pressure, decrease in PVR, and no change in cardiac index or pulmonary artery pressure. These findings suggest that in Fontan patients vasopressin may be an option for treating systemic hypotension during sedation or general anesthesia.

2023 in Review

“…Other methodology articles covered consent/assent (27, 28), and coenrollment (29). Finally, there were reports of interventions in three areas of practice: RCT of “bundled-consent” for PICU procedures (30); open-label study of vasopressin in the Fontan circulation (31); and a stepped-wedge cluster-randomized study of infant kidney dialysis and ultrafiltration (32).…”

The Fontan Circulation Holds Water: The Impact of Arginine Vasopressin on the Fontan Circulation*

“…Nearly 50 years later, we are still dissecting the unique aspects of this circulation. In this issue of Pediatric Critical Care Medicine , the study by Adamson et al (2) reported the hemodynamic effects of arginine vasopressin (AVP) in the Fontan circulation. These findings and their interpretation provide further insight into the potential role of AVP in the acute management of Fontan patients.…”

“…Twenty-eight pediatric and adult Fontan patients (median age 13.5 yr) referred for cardiac catheterization for hemodynamic assessment and/or intervention were given a bolus of AVP followed by a continuous infusion (2). Twelve of these patients had met the criteria for “Fontan dysfunction” and three patients (11%) were fenestrated.…”