What is the source event of infectious respiratory particles release during bronchoscopy: a prospective environmental study.

BACKGROUND

Bronchoscopy is recognized as an aerosol-generating procedure. However, it remains unclear whether standard infection control measures adequately mitigate the release of infectious respiratory particles (IRPs). Quantifying IRP release and identifying the source events are crucial for developing policies.

METHODS

An environmental study was performed involving real-time particle monitoring during bronchoscopy in conscious patients. An optical particle sizer and a viable cascade impactor were used to monitor particle concentrations and airborne bacteria, respectively. All procedural events and patient reactions were documented to allow for temporal correlation.

RESULTS

Reflexive coughing occurred in 94% of procedures and was the source of IRP release. Coughing increased the concentration of 0.5 μm particles by a median of 37,183.95 N/L, a value two orders of magnitude above the baseline level. Although mask use mitigated IRP release, it did not completely prevent it. In the absence of coughing, neither scope insertion nor bronchoalveolar lavage generated significant levels of particles. Furthermore, airborne Acinetobacter baumannii was detected during the procedures.

CONCLUSION

The current standard infection control measures during bronchoscopy are inadequate. Reflexive cough is nearly ubiquitous and the main source of significant, containment-breaching IRP release. Masks may offer partial mitigation, but the real-world effectiveness is limited. Static air cleaning alone is insufficient for real-time management of episodic particle release. Further research into source-control technologies, such as a sealed oral interface that contains cough while preserving nasal access, and into dynamic air management strategies, is warranted to minimize infection risk.

APPROVAL NUMBER: IIT20240332B-R1.