Pilot randomized study comparing two techniques of airway anaesthesia during curvilinear probe endobronchial ultrasound bronchoscopy (CP-EBUS)

Background and objective: This study evaluates two different techniques for topically anaesthetizing the airway with lidocaine during curvilinear probe endobronchial ultrasound bronchoscopy (CP-EBUS): standard injection through the working channel and spray catheter application. Methods: This was a randomized, non-blinded, single-centre pilot study. Patients with plans for CP-EBUS under moderate sedation were enrolled. All patients received nebulized lidocaine followed by posterior oropharyngeal lidocaine via atomizer and a cotton ball swab using McGill forceps. Patients were then randomly assigned to lidocaine administration using spray catheter instillation or direct application through the working channel. Lidocaine was administered in a uniform fashion by a single investigator throughout the study. The primary end-point was the number of significant coughing episodes in the first 30 min of bronchoscopy. Other end-points included lidocaine and intravenous sedation medication dosage; severe coughing session; and number of transbronchial needle aspirations. Results: Forty patients were included in the study: 20 patients in each group. The median numbers of coughing episodes in the first 30 min were 1 (spray catheter group) and 2 (standard injection group) (P < 0.004). Six patients in the standard installation group experienced severe coughing sessions, while there was none in the spray catheter group (P = 0.02). There were no statistical differences between the groups in the dosage of lidocaine or intravenous sedation medications used. There were a greater number of transbronchial needle aspirations performed in the spray catheter group (P = 0.008). Conclusions: Lidocaine delivery via the spray catheter reduced the number of significant coughing episodes compared with standard working channel injection during CP-EBUS. Larger studies are needed to confirm these exploratory findings.