Study of 0.5% lidocaine alone and combination of 0.25% lidocaine with fentanyl and vecuronium in intravenous regional anesthesia for upper limb surgeries.

Background And Objective: Intravenous regional anesthesia (IVRA) for upper limb surgeries with traditional high dose of lidocaine can lead to life threatening side effects. In order to avoid these potential life threatening side effects, many modified techniques of IVRA have been attempted by using a low dose of lidocaine, muscle relaxant and opioid.

Method: The present study is carried out in sixty unpremedicated ASA Class 1 and 2 patients to compare the sensory and motor characteristics, cardio-respiratory parameters and side-effects during intra-operative and post-tourniquet deflation period between the patients who received 40mL of 0.5% lidocaine alone (n=30) and those who received a combination of 40mL of 0.25% lidocaine with 0.05mg fentanyl and 0.5mg vecuronium (n=30) in IVRA for upper limb orthopedic surgeries. The results were analyzed for statistical significance using a paired student t test.

Results: The difference between the two groups regarding the mean time of onset and complete sensory and motor block was statistically significant. But 15 minutes after the injection of anesthetic solution, there was complete sensory and motor block in both groups.

Conclusion: Although the short delay observed in the onset and attainment of complete sensory and motor block may theoretically delay the start of surgery for 10-15 minutes but clinically that time will be spent in the preparation of surgical field. So this combination can be used safely and effectively in intravenous regional anesthesia for upper limb orthopedic surgeries with reduced chance of local anesthetic toxicity.