A double-blind trial of the combination effect of lidocaine, ketamine and verapamil in intravenous regional anesthesia

Abstract

BackgroundThe aim of this study was to evaluate the effects of adding two different doses (2.5 mg or 5 mg) of verapamil to lidocaine ketamine (0.5 mg/kg) during Intravenous Regional Anesthesia (IVRA) compared with lidocaine with ketamine alone.MethodsSeventy-five patients, aged 18–50 years, ASA physical status I and II undergoing elective hand or forearm surgery under Bier’s Block lasting one to one and half hours were included in this randomized controlled double-blind study. Patients were divided into three groups, 25 each to receive either group (I, control group) received 40 ml of 0.5% Lidocaine plus ketamine (0.5 mg/kg), group (II) received as group I plus verapamil 2.5 mg or group (III) received as group I plus verapamil 5 mg for IVRA. Postoperative assessment of block characteristics, sedation, pain, first time for rescue analgesia, hemodynamic changes and side effects were evaluated over a period of 12 h.ResultsBlock characteristics were significant in groups II and III compared with group I. There were significant hemodynamic changes, sedation score, pain score and delayed first request for analgesics postoperatively in groups (II) and (III) compared to group (I) postoperatively. There was no significant difference in group (III) compared to group (II) postoperatively. The incidence of postoperative side effects were more in group (III).ConclusionAdding verapamil 2.5 mg to Lidocaine plus ketamine (0.5 mg/kg) for IVRA was effective and safe adjuvant for acute pain after surgery.