The hemodynamic effect of dopamine in children

Although dopamine is a useful therapeutic agent to augment cardiac function in adults, there is little information about the hemodynamic effects of dopamine in children. To delineate the hemodynamic effects of dopamine in children, we infused two doses of dopamine (2 and 7.75 micrograms/kg/min) into 10 children during diagnostic cardiac catheterization. We measured heart rate, systemic arterial, pulmonary arterial, right atrial, and pulmonary capillary blood pressure, and cardiac output. During infusion of 7.75 micrograms/kg/min of dopamine, cardiac index increased from 3.9 to 5.4 L/min/m2, stroke volume increased from 43 to 57 ml/stroke and systemic vascular resistance declined from 1,697 to 1,165 dynes-cm-5-sec-m2. These indices also were changed significantly from control during infusion of 2 micrograms/kg/min of dopamine. The ratio of mean pulmonary arterial blood pressure to mean systemic arterial blood pressure in one patient with pulmonary vascular obstructive disease increased from 0.73 to 1.15, and ventricular bigeminy occurred during infusion of 7.75 micrograms/kg/min of dopamine. Dopamine is a potentially useful inotropic agent in children, but the use of dopamine may be contraindicated in patients with elevated and fixed vascular resistance.