Bilateral Superior Laryngeal Nerve Block to Attenuate the Pressor Response of Laryngoscopy and Intubation in Adult Patients Undergoing Elective Surgeries Under General Endotracheal Anesthesia: A Randomized Controlled Double-blind Study.

Abstract

Background: Laryngoscopy and endotracheal intubation are essential for airway management but provoke a transient pressor response characterized by hypertension and tachycardia. This reflex sympathetic stimulation can pose significant risks to patients with cardiovascular comorbidities.

Objectives: To evaluate the efficacy of ultrasound-guided bilateral superior laryngeal nerve block (SLNB) using 2% lidocaine in attenuating hemodynamic responses and reducing postoperative airway complications during elective surgeries under general anesthesia.

Methodology: This randomized double-blind controlled study included 234 adult patients aged 18-60 years with American Society of Anesthesiologists I and II physical status, divided into Group-L (lidocaine, n = 117) and Group-N (normal saline, n = 117). Hemodynamic parameters-heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP)-were recorded at baseline, postinduction, and at defined intervals postlaryngoscopy and intubation. Postextubation complications, including cough, hoarseness, and sore throat, were assessed at 0, 2, 6, and 24 h.

Results: Group-L showed significantly attenuated HR, SBP, DBP, and MAP compared to Group-N (P < 0.001 at all-time points). Postoperative airway complications were significantly lower in Group-L immediately postextubation (P < 0.05) but comparable between groups at 6 and 24 h.

Conclusions: Ultrasound-guided SLNB effectively attenuates the pressor response to laryngoscopy and intubation and reduces immediate postoperative airway complications. This technique offers a safe and effective strategy for haemodynamic stability in perioperative care.