DOES USE OF AN ENDOSCOPIC PATIENT FACEMASK REDUCE PARTICLE AEROSOLIZATION DURING UPPER ENDOSCOPIC PROCEDURES? A PROSPECTIVE RANDOMIZED CONTROLLED TRIAL

ABSTRACT

Background: The COVID-19 pandemic has heightened awareness surrounding the danger of aerosolizing procedures which may lead to viral transmission. Most viruses are spread via droplets which are predominantly 5-10 microns (mm) in size and can remain suspended in the environment for extended periods of time. While personal protective equipment may reduce some risk, this prolonged suspension of infectious droplets may still lead to transmission. Furthermore, there is little data describing the risk of aerosolization during upper endoscopic procedures. We sought to characterize particle aerosolization between patients undergoing upper endoscopy with and without an endoscopic patient facemask. Methods: Adult patients scheduled for elective upper endoscopic procedures under monitored anesthesia care at a tertiary care center between August and October 2021 were prospectively enrolled. Patients were randomized to either receive an endoscopic facemask designed with fenestrated openings for endoscope insertion (Procedural Oxygen Mask, Simi Valley, CA) or undergo endoscopy with no mask using nasal cannula oxygen support. Exclusion criteria included requiring endotracheal intubation or medically needing an endoscopic facemask for oxygen delivery. Particle aerosols were measured using a commercially available particle detector (Met One GT-526S, Grants Pass, OR) which measured particles of six different sizes (<0.3mm, 0.3-0.5mm, 0.5-0.7mm, 0.7-1mm, 1-5mm and 5- 10mm). The device was placed at 1 foot from the subject's mouth and equidistant between the endoscopist and the anesthesia staff. Measurements were taken every 5 seconds for analysis. A linear mixed effects model was used to analyze the difference in particle aerosolization between groups. Results: Out of 57 patients who were randomized, 27 underwent endoscopy with a facemask and 30 underwent endoscopy with no mask. There were no significant differences in age, gender, body mass index, Mallampati score, patient positioning, or American Society of Anesthesiology (ASA) score between the 2 groups. Analysis of 27,724 measurements showed no difference in particle aerosolization of any size particle between the 2 study arms. The predictive model demonstrated a trend of decreasing particles during endoscopy which then increased by the end for all six particle sizes for both groups. Conclusions: Use of a widely available endoscopic patient facemask did not prevent particle aerosolization during upper endoscopic procedures. Interestingly, there was an initial decrease in particle counts during the procedures followed by a subsquent increase which may reflect heightened aerosolization with insertion and removal of the endoscope. Further study is warranted to determine if additional interventions may be useful for preventing particle aerosolization during endoscopy and improving safety for all health care staff. (Table Presented) (Figure Presented)