Gastroenterology Procedures Generate Aerosols: An Air Quality Turnover Solution to Mitigate COVID-19’s Propagation Risk

Abstract

The growing fear of virus transmission during the 2019 coronavirus disease (COVID-19) pandemic has called for many scientists to look into the various vehicles of infection, including the potential to travel through aerosols. Few have looked into the issue that gastrointestinal (GI) procedures may produce an abundance of aerosols. The current process of risk management for clinics is to follow a clinic-specific HVAC formula, which is typically calculated once a year and assumes perfect mixing of the air within the space, to determine how many minutes each procedural room refreshes 99% of its air between procedures when doors are closed. This formula is not designed to fit the complex dynamic of small airborne particle transport and deposition that can potentially carry the virus in clinical conditions. It results in reduced procedure throughput as well as an excess of idle time in clinics that process a large number of short procedures such as outpatient GI centers. We present and tested a new cyber-physical system that continuously monitors airborne particle counts in procedural rooms and also at the same time automatically monitors the procedural rooms’ state and flexible endoscope status without interfering with the clinic’s workflow. We use our data gathered from over 1500 GI cases in one clinical suite to understand the correlation between air quality and standard procedure types as well as identify the risks involved with any HVAC system in a clinical suite environment. Thanks to this system, we demonstrate that standard GI procedures generate large quantities of aerosols, which can potentially promote viral airborne transmission among patients and healthcare staff. We provide a solution for the clinic to improve procedure turnover times and throughput, as well as to mitigate the risk of airborne transmission of the virus.

Visualizing endoscopy-generated aerosols with laser light scattering (with videos)

“…During the pandemic, measures used by endoscopy facilities to prevent exposure during GI endoscopy led to workflow disruptions, mainly with regard to lengthy procedure room turnover times, reductions in procedure capacity, and worsened staff working conditions (ie, implementing new safety protocols, reprocessing facilities, donning and doffing PPE, etc), despite a lack of evidenced-based analysis of the potential for airborne transmission during GI endoscopy. 14 By visualizing endoscopy-generated droplet aerosols, our study helps identify procedures that pose the greatest risk for aerosolization during standard GI endoscopy. These findings can help better inform clinical guidelines on appropriate PPE and other measures for transmission risk mitigation during GI endoscopy while allowing healthcare workers to continue to deliver safe and efficient care.…”

Guidelines for Robotic Flexible Endoscopy at the Time of COVID-19

“…Current endoscopic procedures rely on PPE (enhanced during COVID-19), comprehensive room and equipment cleaning and of course air circulation ( Garbey et al, 2020 ) which can vary for endoscopy suites. Despite concerns around patient exposure to the virus due to contaminated endoscopes, evidence suggests that reprocessing agents with viricidal activity will remove the SARS-CoV-2 virus ( Kampf et al, 2020 ; Rai, 2020 ).…”

“…Apart from that, there is a need for evaluation of mechanical barriers and extractors currently employed in the hospitals to provide best and uniform guidelines for clinicians working during a pandemic. Air filtration is another key aspect in reducing HCW exposure to any potential aerosols ( Garbey et al, 2020 ).…”

COVID-19: Effect on gastroenterology and hepatology service provision and training: Lessons learnt and planning for the future

“…Therefore, the importance of air flow was imperative, as it was recognised that post-procedure turnover time or ‘down-time’ was required to let aerosolised particles settle and therefore reduce potential cross-infection. The down-time is dependent on air flow cycles within the procedure room to reduce the particulate burden of air, the procedure type and the Covid status of patient[ 37 ]. Infection control reviews of some units revealed suboptimal air exchange in endoscopy rooms and a lack of infection prevention training in some units.…”