Background: Several additives have been suggested to enhance analgesic effect of local anesthetic agents to decrease the adverse effects of them and increase the degree of satisfaction. We designed this randomized double-blind controlled study to evaluate the analgesic efficacy of the neostigmine added to bupivacaine using spinal anesthesia in patients undergoing lower limb orthopedic surgery.
Methods: Sixty patients 18-80 yr old American Society of Anesthesiologists (ASA) physical status I or II, scheduled for femur surgery under spinal anesthesia, were recruited in a prospective, double-blinded, randomized way.