Attenuation of Hemodynamic Responses to Laryngoscopy and Intubation- Lignocaine versus Esmolol in 100 Cases

Open Access

Abstract

Background: Laryngoscopy and endotracheal intubation cause sympathetic stimulation producing tachycardia and hypertension which may be harmful in patients with cardiovascular disease. This randomized study compared intravenous lignocaine and esmolol for attenuation of this pressor response. Methods & Materials: 100 adult patients (ASA I–II) undergoing elective surgery under general anesthesia were randomized into two groups of 50 each. Group L received lignocaine 1.5 mg·kg⁻¹ IV 90 seconds before laryngoscopy; Group E received esmolol 1.0 mg·kg⁻¹ IV 90 seconds before laryngoscopy. Hemodynamic variables (heart rate [HR], mean arterial pressure [MAP]) were recorded at baseline (T0), after induction but before study drug (T1), immediately after intubation (T2), and at 1 (T3), 3 (T4) and 5 (T5) minutes after intubation. Primary endpoint: peak change in HR and MAP from baseline. Secondary endpoints: incidence of significant tachycardia (>20% increase), hypotension (MAP <65 mmHg), bradycardia (HR <50 bpm), and adverse events. Results: Both drugs attenuated the pressor response compared with historical untreated responses, but esmolol produced significantly less increase in HR and MAP at T2–T4. Mean peak HR change at T2: Group L +18.6 ± 9.4 bpm vs Group E +4.2 ± 7.8 bpm (p < 0.001). Mean peak MAP change at T2: Group L +16.8 ± 10.2 mmHg vs Group E +6.9 ± 8.5 mmHg (p < 0.001). Clinically significant tachycardia occurred in 28/50 (56%) of Group L and 6/50 (12%) of Group E (p < 0.001). Two patients in Group E had transient bradycardia responsive to atropine. No episode of sustained hypotension requiring vasopressor occurred. Conclusion: A single IV bolus of esmolol 1.0 mg·kg⁻¹ given shortly before laryngoscopy attenuates the hemodynamic response to intubation significantly better than lignocaine 1.5 mg·kg⁻¹ in ASA I–II adults. Esmolol may be preferred when a rapid, short-acting sympatholytic effect is desired.