Comparison between clonidine and verapamil as additives to local anesthetic for intravenous regional anesthesia

ABSTRACT

This study compared the effect of addition of clonidine or verapamil to 0.5% lidocaine for intravenous regional anesthesia [IVRA] on the onset of sensory and motor block, duration of postoperative analgesia, recovery of sensory function and hemodynamic response to tourniquet. Sixty patients scheduled for minor orthopedic surgery in the hand and forearm were randomly allocated into one of three groups. All patients received 40 ml of 0.5% of lidocaine together with 5 ml of an additive. The additive was saline in group A, clonidine 2 mug kg -1 in group B and 5 mg verapamil in group C. The results revealed that the onset of complete sensory block proved to be significantly faster in patients received clonidine and verapamil than the control group. The return of sensory function was significantly slower in clonidine group and verapamil group, the tourniquet pain scores were significantly better in clonidine and verapamil groups and the hypertensive response to the tourniquet was attenuated in both groups