Large-dose epinephrine reduces skeletal muscle blood flow under general anesthesia in rabbits.

The goal of this study was to investigate the effect of an epinephrine continuous infusion on muscle blood flow in rabbits. Sixteen male Japan White rabbits were randomly allocated to 1 of 2 groups: epinephrine continuous infusion at 0.01 μg/kg/min (Ep-0.01 group, n = 8) and at 0.1 μg/kg/ min (Ep-0.1 group, n = 8). The observed variables were heart rate, femoral artery blood pressure, common carotid artery blood flow (CCBF), masseter muscle blood flow (MBF), and quadriceps muscle blood flow (QBF). In the Ep-0.01 group, CCBF, MBF, and QBF were increased by 14, 22, and 21% from respective control values. In contrast, in the Ep-0.1 group, CCBF, MBF and QBF were decreased by 10, 30, and 27% from respective control values. There were no differences in the percentage change between MBF and QBF during epinephrine continuous infusion. Positive correlations were observed between CCBF and MBF and between CCBF and QBF. In conclusion, skeletal muscle blood flow was increased during the small-dose epinephrine infusion, whereas it was decreased during large-dose infusion.