Aims: Laryngoscopy and endotracheal intubation are critical steps in general anesthesia and elicit significant sympatho-adrenal responses. Mitigating these responses is essential for safely inducing anesthesia, especially in patients with cardiac or cerebrovascular disease, as these responses can lead to serious complications. This study evaluated the effectiveness of two methods of administering lidocaine in attenuating the hemodynamic response to laryngoscopy and endotracheal intubation. Materials & Methods: In this experimental study,78 patients were divided into three groups (each 26 members). The control group received 5ml of intravenous normal saline and induction drugs. The intravenous lidocaine group received 1.5mg/kg of 2% intravenous lidocaine 2 minutes before laryngoscopy and intubation. The nebulized lidocaine group was administered 4ml of 2% lidocaine via a cirrus nebulizer with a 5L/min oxygen flow, usually 10 to 15 minutes, followed immediately by induction. Findings:Demographic data across the three groups showed no significant differences. However, when comparing the control and nebulized lidocaine groups, nebulized lidocaine had a significant advantage in attenuating hemodynamic responses. Comparisons between the control and intravenous lidocaine groups revealed significant differences in some readings, indicating an incomplete blunting effect. Conclusion: Nebulized lidocaine is more effective than intravenous lidocaine in reducing the hemodynamic changes associated with direct laryngoscopy and endotracheal intubation.
