Aim
The objective of this study is to evaluate the analgesic efficacy of local anesthetic (LA) agents on pain severity among patients undergoing thyroid fine needle aspiration biopsy (FNAB).
Design
A systematic review and meta-analysis of randomized controlled trials (RCTs).
Methods
Digital databases, including PubMed, Scopus, Cochrane, Web of Science, and Google Scholar, were systematically screened from inception till December 2022. The Cochrane risk of bias tool (ROB 2) was used to evaluate the quality of each RCT. The primary outcome (pain severity) was gathered as a mean difference (MD) with a 95% confidence interval (Cl), under the random-effect model.
Results
Overall, 444 patients were enrolled in five RCTs. Regarding pain severity via the visual analogue scale (VAS) assessment tool, the overall effect size showed no substantial difference between LA and control groups ( = 4 RCTs,MD = −8.45, 95% CI [−27.41, 10.52],  = 0.38). Regarding pain severity via the numerical rating scale (NRS) assessment tool, the overall effect size showed no substantial difference between LA and control groups ( = 3 RCTs,MD = −0.85, 95% CI [−3.14, 1.45],  = 0.47).
Conclusion
We have found that the pain levels between the LA and control-receiving groups were comparable. Hence, we concluded that LA before FNAB provides no benefit, especially for one needle puncture and sampling.