The Minimal and Optimal Concentration of Bupivacaine for Epidural Anesthesia in Mastectomy

Objective To determine the minimal and optimal concentration of Bupivacaine for epidural block in mastectomy. Methods Seventy five patients for mastectomy, classified as level ⅠorⅡ in terms of ASA evaluation, will be operated under epidural anesthesia with Bupivacaine. We puncture from T_ 2-3 and leave the tube in the epidural cavity ranged from 3.5 cm to 4cm toward the head. Different concentrations of Bupivacaine, range from 0.20% to 0.07%, are accessed by sequential dilution. We test initially with 5ml ...