Hemodynamic Effects of Amrinone in Children After Fontan Surgery

After Fontan repair in children, we performed a prospective, open-label study to evaluate the effect of amrinone on pulmonary vascular resistance (PVRI). Eight patients who underwent the Fontan repair had baseline arterial pressure, left atrial pressure, central venous pressure, and cardiac output measured postoperatively. Hemodynamic measurements were repeated after amrinone 4.5 mg/kg. The PVRI tended to decrease, but the change was not statistically significant. Although the systemic vascular resistance decreased to 802 +/- 222 from 941 +/- 191 dynes centered dot s centered dot cm-5 centered dot m-2 (P < 0.05), mean arterial blood pressure was unchanged. Cardiac index (3.8 +/- 1.2 to 4.7 +/- 1.6 L centered dot min-1 centered dot m-2) and stroke volume index (23.6 +/- 6.7 to 30.5 +/- 8.1 mL centered dot beat-1 centered dot m-2) increased, and heart rate decreased (160 +/- 21 to 151 +/- 24 bpm) (P < 0.05). Colloid transfusion during amrinone bolus administration was 13.9 mL/kg. The mean serum amrinone concentration was 4.2 micro gram/mL at the end of bolus and clearance was 2.24 mL centered dot kg-1 centered dot min-1. Arrhythmias and thrombocytopenia were not noted. We conclude that amrinone administration is effective in increasing cardiac output in children who have undergone a Fontan repair. (Anesth Analg 1996;82:241-6)