Lidocaine for preventing postoperative sore throat

Area of Science:

• Anesthesiology
• Pharmacology

Background:

• Postoperative sore throat is a common complication of general anesthesia and tracheal intubation, affecting 30-70% of patients.
• Factors influencing sore throat include endotracheal tube type, diameter, and cuff pressure.
• Prophylactic medications, such as local anesthetics and steroids, are explored to mitigate this side effect.

Purpose of the Study:

• To evaluate the efficacy and safety of prophylactic topical and systemic lidocaine for preventing postoperative sore throat in adults undergoing general anesthesia with endotracheal intubation.

Main Methods:

• A systematic review and meta-analysis of randomized controlled trials (RCTs) were conducted.
• Searches included CENTRAL, MEDLINE, and EMBASE databases, with updated searches in February 2015.
• Nineteen RCTs involving 1940 participants were included, comparing lidocaine therapy to control groups.

Main Results:

• Lidocaine therapy (topical or systemic) appeared to reduce the risk of postoperative sore throat (Risk Ratio 0.64, 95% CI 0.48 to 0.85), though evidence quality was low.
• When only high-quality trials were considered, this effect was not statistically significant.
• Lidocaine significantly reduced the severity of sore throat as measured by a visual-analogue scale (Mean Difference -10.80, 95% CI -14.63 to -6.98).

Conclusions:

• While results suggest a potential benefit of lidocaine in reducing postoperative sore throat, findings should be interpreted with caution due to low-quality evidence.
• The effectiveness of lidocaine is influenced by study quality, drug concentration, administration route, cuff pressure management, patient population, and outcome measurement.
• Adverse effects of lidocaine were not well-reported in the included studies, though toxicity is generally rare.