A Comparative Study of Lignocaine and Nitrous Oxide for Rocuronium Injection Pain

Background: Pain is a common side effect of rocuronium bromide and this study has been undertaken to compare the effect of nitrous oxide and lignocaine in reducing the rocuronium injection pain in adult patients. Materials and Methods: After ethical committee approval, 80 adult patients of age 18-65 years and ASA I and II who underwent elective surgery from October 2011 and September 2013 in the Regional Institute of Medical Sciences, Imphal were randomly assigned into one of the two groups: Group O (n = 40) received 100% oxygen for 2 min as preoxygenation; Group N (n = 40) received 50% nitrous oxide and 50% oxygen mixture for 2 min as preoxygenation. After 2 min., 2 ml of 2% lignocaine was given with the forearm occluded and then released after 1 min. followed by the injection of subparalyzing dose of rocuronium (0.06 mg/kg) and the patients were enquired about the degree of pain. Anaesthesia was then induced with injection thiopentone sodium (2.5%) 5 mg/kg and then a paralyzing dose of rocuronium (0.6 mg/kg) was given to facilitate intubation. The airway was secured and any withdrawal movements were noted. Results: It was observed that the combination of nitrous oxide and lignocaine (Group N) reduced rocuronium injection pain more than lignocaine alone (Group O) (5% vs. 25%; P < 0.05). Moreover, withdrawal movements were also less in group N compared to group O (5% vs. 22.5%; P < 0.05). Conclusion: It may be concluded that two different analgesic modalities nitrous and lignocaine effectively prevent pain and withdrawal movements associated with rocuronium injection.