Effect of dexamethasone and lidocaine combination on incidence of post-operative sore throat: A meta-analysis and trial sequential analysis.

BACKGROUND

Postoperative sore throat (POST) is a common complication after endotracheal intubation, occurring in 30-50 % of patients. While lidocaine (local anesthetic) and dexamethasone (anti-inflammatory) are used individually to prevent POST, their combined efficacy remains unclear. This meta-analysis synthesizes evidence from randomized controlled trials to determine whether Intravenous dexamethasone-lidocaine combination is more effective than dexamethasone alone in reducing POST incidence.

METHODS

A systematic search was conducted across PubMed, Embase, and Web of Science to identify studies comparing the effect of dexamethasone with and without lidocaine on the incidence of POST, cough, and hoarseness. Statistical analysis was performed on RevMan. Data were pooled using a random-effects model (Mantel-Haenszel method), with results reported as risk ratios (RR) and 95 % confidence intervals (CIs); heterogeneity was assessed using the I2 statistic. A p-value less than 0.05 was considered statistically significant. We use Gradpro GDT and Trial sequential analysis to assess the certainty and reliability of evidence, respectively.

RESULTS

Our search retrieved 116 articles, of which 31 were duplicates. At the end of the selection process based on prespecified eligibility criteria, three randomized controlled trials were included in the final meta-analysis. Dexamethasone-lidocaine significantly reduces the incidence of POST compared to dexamethasone alone, with a (RR: 0.53; 95 % CI: 0.37-0.75; P = 0.0003, I2 = 0 %). The meta-analysis showed no statistically significant difference in postoperative cough (RR: 0.81; 95 % CI: 0.41-1.61; P = 0.55, I2 = 24 %) and hoarseness (RR: 0.60; 95 % CI: 0.29-1.22; P = 0.16, I2 = 24 %) between the dexamethasone-lidocaine combination and dexamethasone alone. Non-significance doesn't prove groups are comparable; wide confidence intervals suggest a potentially meaningful difference in cough incidence. GRADE assessment analysis showed high evidence for POST and cough but showed moderate evidence for hoarseness and cough. Trial sequential analysis showed insufficient evidence to conclude that Dexamethasone-lidocaine reduces the incidence of POST.

CONCLUSION

The dexamethasone-lidocaine combination suggests a clinically meaningful reduction in POST compared to dexamethasone alone, with consistent effects across studies. While not impacting hoarseness and cough, these robust findings support adopting this readily available, cost-effective strategy to enhance recovery after intubation. The combination's benefit on the most common postoperative complications justifies its inclusion in airway management protocols. Further trials are needed to support and enhance the reliability of this current evidence.