Spray nozzle for topical anaesthesia during flexible bronchoscopy: a randomised controlled trial.

Background: The effectiveness of using a spray nozzle to deliver lidocaine for superior topical airway anaesthesia during non-sedation flexible bronchoscopy (FB) remains a topic of uncertainty when compared with conventional methods.

Methods: Patients referred for FB were randomly assigned to receive topical lidocaine anaesthesia via the bronchoscope's working channel (classical spray (CS) group) or through a washing pipe equipped with a spray nozzle (SN group). The primary outcome was cough rate, defined as the total number of coughs per minute. Secondary outcomes included subjective perceptions of both the patient and operator regarding the FB process. These perceptions were rated on a visual analogue scale, with numerical ratings ranging from 0 to 10.

Results: Our study enrolled a total of 126 (61 CS group; 65 SN group) patients. The SN group exhibited a significantly lower median cough rate compared with the CS group (4.5 versus 7.1 counts·min^-1; p=0.021). Patients in the SN group also reported less oropharyngeal discomfort (4.5±2.7 versus 5.6±2.9; p=0.039), better tolerance of the procedure (6.8±2.2 versus 5.7±2.7; p=0.011) and a greater willingness to undergo a repeat FB procedure (7.2±2.7 versus 5.8±3.4; p=0.015) compared with those in the CS group. From the operator's perspective, patient discomfort (2.7±1.7 versus 3.4±2.3; p=0.040) and cough scores (2.3±1.5 versus 3.2±2.4; p=0.013) were lower in the SN group compared with the CS group, with less disruption due to coughing observed among those in the SN group (1.6±1.4 versus 2.3±2.3; p=0.029).

Conclusions: This study illustrates that employing a spray nozzle for the delivery of lidocaine provides superior topical airway anaesthesia during non-sedation FB compared with the traditional method.