[Measurement of portal blood flow in man by a continuous local thermodilution method. III. Effects of dopamine on systemic and portal hemodynamics after hepatectomy].

We gave dopamine (3 micrograms/kg/min, 30 min) intravenously on the third day after hepatectomy to 19 patients, and studied the effects of the drug on systemic and portal hemodynamics. In another 42 patients, administration of dopamine at the same rate was started soon after hepatectomy and continued for about 2 weeks; the clinical results were evaluated. After hepatectomy, the systemic hemodynamics were hyperdynamic and the portal hemodynamics were hypodynamic. After 30 min of dopamine administration, the oxygen pressure in portal blood increased, and because portal blood flow also increased, the oxygen delivery to the liver increased. The mechanism involved an increased proportion of portal venous flow to cardiac output, and a decrease in the splanchnic resistance, not portal venous resistance. Probably, specific dopamine receptors played important role in the increase in the superior mesenteric arterial blood flow. Among 42 patients given small dosage of dopamine, the clinical symptoms of five of seven who had developed liver failure improved. None of the other 35 patients given dopamine preventively developed liver failure. Dopamine in small doses is useful for the management of liver failure after liver resection.