Tamer A. Moaein, MD, Wayne J. Manishen, MD; University of Manitoba, Winnipeg, MB, Canada
Introduction: Concerns over COVID-19 aerosol release during upper endoscopy has led to recommendations for negative pressure rooms, prolonged air-settling times and HEPA filtration machines. The resulting procedural inefficiency has led to prolonged patient wait times. Although N-95 masks can protect staff from viral exposure, potential environmental contamination remains an issue for room turnover times. Oxygen procedural masks were originally developed to avoid hypoxemia in patients undergoing bronchoscopy in intensive care units. It has been suggested that these devices be considered for patients undergoing upper GI endoscopy to reduce aerosol release, but to date, no studies have been performed to confirm their effectiveness in protecting the procedure room environment. Methods: A procedural mask with three self-sealing ports that can accommodate almost any endoscope (Explorer, Intersurgical Berkshire, UK), was attached to a T- piece containing an oxygen inlet (Vyaire, Mettawa, IL) . The expiratory port was connected to a N-95 round anesthesia filter (Flo-Guard, Intersurgical ) to protect the environment from airborne pathogens. The procedural mask was applied to an adult CPR mannequin with elastic straps to ensure a secure fit. A fluorescent powder and mist ( Glo Germ Company, Moab, UT, USA) with particle sizes between 1 and 5um (SARS-COV-2 is 0.7-1.2um) was injected into the trachea of an adult CPR mannequin to simulate a cough. An endoscope was placed into one port of the mask and a suction catheter was placed into another opening to simulate an actual upper endoscopy. The degree of fluorescein staining on paper outside the mask was assessed with ultraviolet light detection in a darkened room. Results: Preliminary results using our cough simulation model without a procedural mask revealed a widespread dissemination of fluorescent droplets, contaminating the surrounding area. The use of a patient procedural mask significantly reduced the aerosol dispersion and contamination surrounding the patient. Discussion: Our preliminary findings provide proof-of-concept support for use of a patient procedural mask apparatus to reduce environmental exposure to cough-generated aerosols and droplet sprays during upper GI endoscopy. While the patient procedure mask provides environmental protection and may reduce the need for prolonged air-settling and HEPA filtration, it should not replace the appropriate use of personal protective equipment by endoscopy staff in case of patient procedural mask dislodgement.
Figure 1. Endoscope insertion into patient procedural mask with oxygen T piece and N-95 expiration filter
Disclosures: Tamer Moaein indicated no relevant financial relationships. Wayne Manishen indicated no relevant financial relationships.