Nebulized lignocaine versus saline in non-sedated flexible bronchoscopy: a double-blind randomized controlled trial

Abstract

Background: Flexible bronchoscopy performed without sedation can cause patient discomfort, coughing, and anxiety, potentially affecting procedural quality. Nebulized lignocaine has been proposed as an adjunct to standard topical anesthesia to improve tolerance, but evidence remains inconsistent.

Methods: In this double-blind, randomized, placebo-controlled trial, 150 adult patients undergoing diagnostic non-sedated flexible bronchoscopy were randomized to receive pre-procedure nebulization with 4 ml 2% lignocaine (n=73) or 4 ml 0.9% saline (n=77), in addition to standard topical anesthesia. Primary outcomes included operator- and patient-rated cough scores assessed by visual analogue scale (VAS). Secondary outcomes included cumulative lignocaine dose, procedural characteristics, complications, and willingness to undergo repeat bronchoscopy. Statistical significance was set at p<0.05.

Results: Operator- and patient-rated cough scores were comparable between groups (3.04±0.79 versus 3.12±0.84, p=0.53; 2.91±0.76 versus 2.98±0.81, p=0.57). Cumulative lignocaine dose was significantly higher in the lignocaine group but did not exceed upper safety limit. (12.2±1.4 ml versus 12.7±1.2 ml, p<0.020). So pre procedural nebulized lignocaine does not produce additional benefit and may be safely omitted during routine flexible bronchoscopy. Procedural timings, complications, and willingness to repeat bronchoscopy did not differ significantly. No adverse events or signs of lignocaine toxicity were observed in either group.

Conclusions: Pre-procedural nebulized lignocaine did not improve cough suppression, procedural comfort, or willingness for repeat bronchoscopy as compared to normal saline. Although it reduced total lignocaine exposure, routine use as an adjunct to standard topical anesthesia provides limited additional benefit and may be safely omitted, particularly in resource-limited settings.