Is Nebulized Lidocaine Adequate Topical Anesthesia for Diagnostic Transnasal Tracheoscopy?

To evaluate if nebulized 4% lidocaine alone provides adequate laryngopharyngeal anesthesia for office-based diagnostic transnasal tracheoscopy (TNT).

A retrospective chart review (January 2011 to June 2014) and a prospective case series (July 2014 to December 2014) of patients who underwent diagnostic TNT were performed at a university voice and swallowing center. TNT cases were categorized by method of topical laryngopharyngeal anesthesia: nebulized 4% lidocaine and 4% lidocaine drip (phase I) and nebulized 4% lidocaine only (phase II).

TNT was performed a total of 59 times on 38 patients. Eleven (69%) of 16 phase I TNT procedures involved significant patient discomfort and severe cough following the lidocaine drip. Forty-two (98%) of 43 phase II TNT procedures were completed comfortably; 1 case required additional anesthesia by lidocaine drip. Retrospectively, 100% (n=8) of patients who underwent both phase I and phase II TNTs were noted to prefer anesthesia with nebulizer alone. In a prospective case series of 14 phase II TNT cases, 6 (86%) of 7 patients who previously underwent phase I TNT reported preference for anesthesia with nebulizer alone.

Nebulized lidocaine appears to provide sufficient laryngopharyngeal anesthesia for diagnostic TNT. It is preferred by patients over laryngeal drip.