Recently, interest has been increased on the role of catecholamines in extrarenal potassium homeostasis. This study has undertaken to investigate the effects of epinephrine added to lidocaine for axillary block in HR, MAP, ABG, blood sugar and electrolytes (Na+, K+), and the effects of propranolol, beta-adrenergic blocker, on the data. The patients admitted to our hospital for operation of upper extremities were divided into three groups. Group I was 10 patients blocked with lidocaine 30 ml. Group II was 14 patients blocked with lidocaine 30 ml with epinephrine 0.3 mg(1:100,000). Group III was 10 patients pretreated with propranolol (10u/kg) and blocked with lidocaine 30 ml with epinephrine. After block, the results were as follows. 1) MAP decreased in all group and group III decreased more than group I. 2) HR increased all group and group III decreased more than group I. 3) ABG showed hypoventilatory pattern due to sedative effect by diazepam (0.15mg/kg). 4) Blood sugar value was increased in group I and II, showed increasing tendency in group III, but this tendency was not significant. 5) Blood K+ concentration decreased significantly and the maximal decrease was 0.5 mEq/L in 30 min after block, but there was not significant decrease in group III. This results indicate that clinical dose of epinephrine(1;100,000) decrease blood K+ concentration significantly and propranolol (10u/kg) pretreatment prevent K+ decreasing effect of epinephrine. In clinical practice, it is suggested that much care must be paid to use of local anesthetics with epinephrine to hypokalemic patients.