Interventions: Systemic hemodynamics, GMBF (laser-Doppler), plasma α-glutathione S-transferase, aspartate aminotransferase, alanine aminotransferase and malondialdehyde were assessed just before catecholamine infusion (T0), as soon as mean arterial pressure (MAP) reached 70-80 mmHg (T1), and 2 (T2) and 6 (T3) hours after T1. Drugs were titrated from 0.2 µg/kg/min with 0.2 µg/kg/min increments every 3 min for epinephrine and norepinephrine, and from 0.5 µg/kg/min with 0.5 µg/kg/min increments every 3 min for dopexamine.