Comparison between transtracheal and intravenous 2% lignocaine in attenuating hemodynamic stress response following direct laryngoscopy and endotracheal intubation: a randomized controlled trial

Background and Aims Lignocaine is used through various routes to mitigate the hemodynamic surge associated with laryngoscopy and endotracheal intubation during general anesthesia. This study hypothesized that post-induction administration of transtracheal 2% lignocaine at 1.5 mg/kg would have a similar effect to intravenous 2% lignocaine at the same dosage, providing an alternative for attenuating the hemodynamic stress response. Methods A total of 138 consenting patients were randomized into two groups. Following induction, Group IV patients received 2% lignocaine at 1.5 mg/kg intravenously, while Group TT patients received 2% lignocaine at 1.5 mg/kg transtracheally. The primary outcome was the comparison of hemodynamic responses at different time points around intubation. The secondary outcome was the incidence of sore throat. Data analyses were done using the Statistical Software Jupyter Notebook, running in a Python 3.11 environment. Results The trend of vitals over time indicated that post-induction hypotension was less pronounced in the TT group. After intubation, patients in the TT group experienced a smaller surge in blood pressure and heart rate compared to the IV group. Notably, mean blood pressure (MBP) at 3 minutes post-intubation has significantly low values in patients who received transtracheal lignocaine [MBP (median with IQR) IV group 79(71-87) mm of Hg vs. TT group 73(65-81) mm of Hg, P = 0.009]. Conclusion Transtracheal lignocaine is more likely to maintain stable hemodynamics at various stages of intubation during general anesthesia compared to intravenous lignocaine. CTRI Registration CTRI/2023/06/054125 [Registered on: 19/06/2023]. This trial is registered with the Clinical Trial Registry of India https://ctri.nic.in/Clinicaltrials/login.php