Is Additional Nebulized Lidocaine Helpful in Flexible Bronchoscopy?: A Meta-Analysis

BACKGROUND: Conflicting evidence of nebulized lidocaine use in bronchoscopy still exist. This study will identify whether there is any difference in various patient-related, physician-related, or procedure-related outcomes with and without lidocaine nebulization before the procedure. METHOD: The authors performed a search in 4 electronic databases, including Pubmed, Scopus, Virtual Health Library, and Google Scholar from inception to August 2019. Data on patient-reported and physician-reported outcomes, doses of sedation, and lidocaine were extracted and pooled into standardized mean difference (SMD) and mean difference (MD) using the random-effect model. RESULTS: Seven randomized controlled trials with 1366 patients were included. Cough was not different between the nebulized lidocaine group and no nebulized lidocaine group (SMD, -0.12; 95% confidence interval, -0.82 to 0.59; I, 95%; P=0.75), so as operator's satisfaction score, ease of the procedure, patient's discomfort, and unwillingness to repeat the procedure. Additional nebulized lidocaine group required higher lidocaine dose (MD, 81.93; 95% confidence interval, 17.14-146.71). Studies using only local anesthesia favored the "no additional lidocaine" group in improving cough, operator's satisfaction score, and ease of the procedure. Subgroup analysis of studies using moderate sedation showed a decrease in midazolam dose and duration of the procedure in the "additional nebulized lidocaine group." CONCLUSION: Additional administration of nebulized lidocaine increased the total dose of lidocaine used and did not improve cough symptoms, operator-satisfaction score, ease of the procedure, and willingness to repeat the procedure. Subgroup analysis of studies using moderate sedation showed a decrease in midazolam use and in procedure duration but the clinical significance of these findings is uncertain.