Effect of Nebulised Lignocaine on the Quality of I-gel Insertion: A Randomised Controlled Trial

Introduction: Supraglottic Airway Devices (SAD) are integral part of airway management during General Anaesthesia (GA) and are less invasive than endotracheal intubation. I-gel is a novel and innovative SAD, with non inflating cuff and it is widely used among available devices. Various drug combinations are being studied to obtain better insertion conditions. Lignocaine nebulisation is popularly used as topical anaesthesia for the airway. Authors hypothesised that it could improve the insertion conditions of the airway in addition to induction agents. Aim: To assess the efficacy of lignocaine nebulisation for I-gel insertion conditions in terms of the frequency of optimal insertion conditions and haemodynamic changes observed during and after the insertion of I-gel. Materials and Methods: This randomised controlled trial was conducted for one year from January 2019 to January 2020 in Karnataka Institute of Medical sciences, Hubli, Karnataka, India. Ninety patients of age group 18 to 45 years, belonging to American Society of Anaesthesiologists’ (ASA) grade I and II, undergoing minor surgical procedures were included. They were randomised into two equal groups, group L received 5 mL of 4% lignocaine and group D received 5 mL of normal saline nebulisation 5 minutes before induction of GA. Optimal insertion conditions (successful insertion at the first attempt without adverse response) and haemodynamic responses were noted down as primary and secondary outcomes respectively. The data was analysed using Chi-square test and Student’s t-test according to parameters. Results: A total of 43 patients were in group lignocaine nebulisation (Group L) and 44 in the normal saline nebulisation group (Group D) and they had the mean age of 28.8±6.3 and 29.0±5.1 respectively. The optimal insertion (p-value 0.26), successful first attempt insertion (p-value 0.175) and time for insertion (p-value 0.512) were not statistically significant between the two groups. In group L at 1 and 5 minutes, fall in Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) was noted and compared with other group which was not statistically significant. Conclusion: Preinduction lignocaine nebulisation doesn’t improve optimal insertion conditions of I-gel statistically. Even though better haemodynamic were noted with the same, it cannot be recommended for the sole purpose by nebulisation route.