Efficacy of paracetamol when added as an adjunct to lignocaine in intravenous regional anaesthesia

Intravenous regional anaesthesia (IVRA) using Lignocaine is a safe, reliable, and cost-effective technique for providing anaesthesia as well as bloodless field during upper limb surgery. It has been postulated that the site of action in IVRA is probably by blockade of small nerves or possibly nerve endings and not the major nerve trunks. A disadvantage of this technique is the rapid return of sensation after tourniquet release resulting in subsequent pain. The ideal IVRA solution should have rapid onset, require less dose of local anaesthetic (LA), reduce tourniquet pain, and prolong post-deflation analgesia. In this study we evaluated the effects of Paracetamol on onset of sensory and motor block time, sensory and motor recovery time and the requirement of postoperative analgesia. METHODS Sixty patients undergoing upper limb extremity surgeries were randomised into two groups .IVRA was achieved by injecting 10 ml of 2% Lignocaine with 30 ml of Paracetamol to total of 40 ml in Group 1(n=30) and 10 ml of 2% Lignocaine with 30 ml of Normal saline to total of 40 ml in Group 2(n=30). Onset of sensory and motor block time noted, intraoperative pain assessed using VAS scores, intraoperative analgesic use and sensory and motor recovery time were noted during the surgery. Postoperative analgesic requirement was noted after the tourniquet deflation. Vital parameters were monitored throughout the operative period. RESULTS Onset of sensory and motor block was shorter and sensory recovery time was longer in Group 1 (p < 0.001). Intraoperative VAS scores were significantly lower in Group 1 (p< 0.05). Intraoperative Fentanyl consumption was 8.33 ± 21.82 mcg in Group 1 and 38 ± 37.82 mcg in Group 2, the number of patients requiring Fentanyl were 4 and 17 respectively ( p< 0.001). The postoperative analgesia requirement was lower in Group 1 with 9 patients and was 25 patients in Group 2 (p< 0.001). CONCLUSION The administration of Paracetamol as an adjunct to Lignocaine in IVRA was found to be efficacious and it provided significant shortening in the onset of sensory block, a decrease in the intraoperative analgesic requirement and an improvement in the post operative analgesia with a reduced need for analgesics in the post operative period