Effects of epinephrine in local dental anesthetics on plasma catecholamine concentration and circulation

To determine the hemodynamic effects of 40 micrograms of epinephrine in local dental anesthetics, circulatory parameters and plasma catecholamine concentrations were measured for 30 minutes after injection of 2% lidocaine with epinephrine (E-L group) or without epinephrine (L-group) in fully conscious healthy young volunteers. The plasma epinephrine concentrations significantly increased in the E-L group (320.9 +/- 47.9 pg/ml) after the injection, but did not change in the L-group. The plasma norepinephrine concentrations did not change in either group after the injection. The differences in each circulatory parameter between both groups (parameters in the E-L group minus those in the L-group) at 5 minutes after the injection were +6% in heart rate, +6% in RPP (rate pressure product), +12% in stroke volume index, +22% in cardiac index, -17% in diastoric blood pressure, -22% in total peripheral resistance, -11% in mean arterial pressure, and +/- 0% in systolic blood pressure. The significant increase in cardiac output and significant reduction in total peripheral resistance results in little change in mean arterial pressure. These results suggest that oral submucosal injection of 40 micrograms of epinephrine accelates the cardiac performance, with little change in blood pressure and heart rate.