Comparative Efficacy of Preoperative Nebulized Dexmedetomidine, Ketamine, and Magnesium Sulphate in Preventing Postoperative Sore Throat after Laparoscopic Surgery under General Anaesthesia

Abstract

Background: Postoperative sore throat (POST) is a frequent and distressing complication after tracheal intubation for general anesthesia, with reported incidence varying widely depending on definitions and populations. Pharmacologic nebulization prior to induction is an attractive, low-risk, topical approach to reduce mucosal inflammation and nociception.

Objective: To evaluate and compare the efficacy of preoperative nebulized dexmedetomidine, ketamine, and magnesium sulphate in preventing POST in adult patients undergoing elective laparoscopic surgery under general anesthesia.

Methods: This randomized, double-blind, three-arm study included 50 adult patients allocated to receive preoperative nebulization 30 minutes before induction: Group D (dexmedetomidine 1 µg/kg diluted to 4–5 mL, n = 17), Group K (ketamine 50 mg diluted to 4–5 mL, n = 17), and Group M (magnesium sulphate 250 mg diluted to 4–5 mL, n = 16). Standardized anesthesia, cuff pressure control (20–25 cmH₂O), and endotracheal tube sizes were used. Primary outcome: incidence of POST at 6 hours post-extubation. Secondary outcomes: incidence at 0, 2, 12, 24 h; severity (4-point scale), hoarseness, cough, sedation, and adverse events. Analysis followed intention-to-treat principles.

Results: Overall, dexmedetomidine showed the lowest incidence of POST at all time points and was significantly superior at the primary endpoint (6 h): 1/17 (5.9%) in Group D vs 4/17 (23.5%) in Group K and 5/16 (31.3%) in Group M (p = 0.04). Severity of POST was predominantly mild and no severe events occurred. Sedation (transient, mild) and two episodes of bradycardia occurred in Group D; no serious adverse events were recorded.

Conclusion: In this 50-patient randomized comparison, preoperative nebulized dexmedetomidine (1 µg/kg) produced a clinically meaningful reduction in incidence and severity of POST compared with nebulized ketamine (50 mg) and nebulized magnesium sulphate (250 mg), with an acceptable safety profile. Larger multicenter trials are warranted to confirm these findings and to refine optimal dosing and timing.

Background: Postoperative sore throat (POST) is a frequent and distressing complication after tracheal intubation for general anesthesia, with reported incidence varying widely depending on definitions and populations. Pharmacologic nebulization prior to induction is an attractive, low-risk, topical approach to reduce mucosal inflammation and nociception.

Objective: To evaluate and compare the efficacy of preoperative nebulized dexmedetomidine, ketamine, and magnesium sulphate in preventing POST in adult patients undergoing elective laparoscopic surgery under general anesthesia.

Methods: This randomized, double-blind, three-arm study included 50 adult patients allocated to receive preoperative nebulization 30 minutes before induction: Group D (dexmedetomidine 1 µg/kg diluted to 4–5 mL, n = 17), Group K (ketamine 50 mg diluted to 4–5 mL, n = 17), and Group M (magnesium sulphate 250 mg diluted to 4–5 mL, n = 16). Standardized anesthesia, cuff pressure control (20–25 cmH₂O), and endotracheal tube sizes were used. Primary outcome: incidence of POST at 6 hours post-extubation. Secondary outcomes: incidence at 0, 2, 12, 24 h; severity (4-point scale), hoarseness, cough, sedation, and adverse events. Analysis followed intention-to-treat principles.

Results: Overall, dexmedetomidine showed the lowest incidence of POST at all time points and was significantly superior at the primary endpoint (6 h): 1/17 (5.9%) in Group D vs 4/17 (23.5%) in Group K and 5/16 (31.3%) in Group M (p = 0.04). Severity of POST was predominantly mild and no severe events occurred. Sedation (transient, mild) and two episodes of bradycardia occurred in Group D; no serious adverse events were recorded.

Conclusion: In this 50-patient randomized comparison, preoperative nebulized dexmedetomidine (1 µg/kg) produced a clinically meaningful reduction in incidence and severity of POST compared with nebulized ketamine (50 mg) and nebulized magnesium sulphate (250 mg), with an acceptable safety profile. Larger multicenter trials are warranted to confirm these findings and to refine optimal dosing and timing.