Nebulization versus standard application for topical anaesthesia during flexible bronchoscopy under moderate sedation - a randomized controlled trial

Abstract

Background: Endobronchial administration of lidocaine is commonly used for cough suppression during diagnostic bronchoscopy. Recently, nebulization of lidocaine during bronchoscopies under deep sedation with fiberoptic intubation using a distinct spray catheter has been shown to have several advantages over conventional lidocaine administration via syringe. However, there are no data about this approach in bronchoscopies performed under moderate sedation. Therefore, this study compared the tolerability and safety of nebulized lidocaine with conventional lidocaine administration via syringe in patients undergoing bronchoscopy with moderate sedation.

Methods: Patients requiring diagnostic bronchoscopy were randomly assigned to receive topical lidocaine either via syringe or via nebulizer. Endpoints were consumption of lidocaine and sedative drugs, as well as patient tolerance and safety.

Results: Sixty patients were included in the study (n = 30 in each group). Patients required lower doses of endobronchial lidocaine when given via nebulizer versus syringe (164.7 ± 20.8 mg vs. 250.4 ± 42.38 mg; p < 0.0001) whereas no differences in the dosage of sedative drugs were observed between the two groups (all p > 0.05). Patients in the nebulizer group had higher mean oxygen saturation (96.19 ± 2.45% vs. 94.21 ± 3.02%; p = 0.0072) and a lower complication rate (0.3 ± 0.79 vs. 1.17 ± 1.62 per procedure; p = 0.0121) compared with those in the syringe group.

Conclusions: Endobronchial lidocaine administration via nebulizer was well-tolerated during bronchoscopies under moderate sedation and was associated with reduced lidocaine consumption, a lower complication rate and better oxygenation compared with lidocaine administration via syringe.

Trial registration: The study was registered with clinicaltrials.gov ( NCT02262442 ; 13^th October 2014).

Keywords: Anaesthesia; Bronchoscopy; Lidocaine; Nebulizers and vaporizers.

Fig. 1

Dosages of administered sedative drugs and lidocaine. Median doses of (a) intravenously administered midazolam (right), propofol (middle), and fentanyl (right), and (b) intrabronchial lidocaine. Boxes represent the interquartile range, whiskers show maximum and minimum, and + indicates mean value

Fig. 2

Pre- and postinterventional arterial blood gas analysis. Arterial pressure of (a) carbon dioxide (PaCO₂) and (b) oxygen (PaO₂) before and after bronchoscopy. Data are given as mean + standard deviation

Fig. 3

Tolerance Scores. Median visual analogue scale (VAS) scores for global tolerance, nausea, asphyxia, cough and pain (0 = non-existent; 100 = unbearable). Boxes represent the interquartile range, whiskers report maximum and minimum, and + indicated mean value