Intravenous Regional Anaesthesia Using Lidocaine and Magnesium-Randomized, Controlled, Double-Blinded Study
Author(s): Kalyani Manasa Rapeti*, Bokka Nageswara Rao and Anil Kumar Poduri
Abstract
Background: Intravenous Regional Anaesthesia (IVRA) is a technically simple, reliable and cost-effective block with high success rates which can be safely used for limb surgeries, magnesium sulphate improves the quality and duration of regional analgesia and anaesthesia techniques. The present study aimed to assess whether magnesium as an adjuvant to lignocaine exerts an added advantage over plain lignocaine in IVRA.
Materials and methods: Hundred patients undergoing various orthopaedic surgeries of forearm were randomized by double blinded technique. One, group L, received IVRA with 40 ml drug solution prepared by mixing 10 ml of Lignocaine 2% with 30 ml of normal saline, while the other group LM received 10 ml Lignocaine 2% with magnesium sulphate 1500 mg (in 10 ml of 15% W/V) and normal saline to make 40 mL. The onset of sensory and motor blockade, the duration of motor blockade, the duration of analgesia (time to first request for analgesic), the mean time of sensory and motor block recovery, quality of block, sedation scores and side effects were noted and compared statistically; p-value<0.05 was considered significant.
Results: The onset of sensory block was significantly earlier in group LM (6.02+0.73) compared to group L (6.43+0.81), p<0.01 and onset of motor block was also significantly earlier in group LM (8.75+1.07) than in group L (9.21+1.07), p<0.01. The duration of motor blockade duration of analgesia and the mean time of sensory and motor blockade recovery was significantly prolonged in group LM compared with group L and the difference was statistically significant. The tourniquet tolerance was better observed in group LM compared to that in group L. The sedation scores, hemodynamic parameters, side effects and complications were comparable in both groups without significant differences.
Conclusion: The addition of magnesium sulphate) to lignocaine for IVRA fastened the onset of sensory and motor blockade, increased the duration of analgesia, prolonged the sensory and motor blockade and improved the tourniquet tolerance significantly when compared to lignocaine used alone.