A Systems Approach to Assess Transport and Diffusion of Hazardous Airborne Particles in a Large Surgical Suite: Potential Impacts on Viral Airborne Transmission

Abstract

Airborne transmission of viruses, such as the coronavirus 2 (SARS-CoV-2), in hospital systems are under debate: it has been shown that transmission of SARS-CoV-2 virus goes beyond droplet dynamics that is limited to 1 to 2 m, but it is unclear if the airborne viral load is significant enough to ensure transmission of the disease. Surgical smoke can act as a carrier for tissue particles, viruses, and bacteria. To quantify airborne transmission from a physical point of view, we consider surgical smoke produced by thermal destruction of tissue during the use of electrosurgical instruments as a marker of airborne particle diffusion-transportation. Surgical smoke plumes are also known to be dangerous for human health, especially to surgical staff who receive long-term exposure over the years. There are limited quantified metrics reported on long-term effects of surgical smoke on staff’s health. The purpose of this paper is to provide a mathematical framework and experimental protocol to assess the transport and diffusion of hazardous airborne particles in every large operating room suite. Measurements from a network of air quality sensors gathered during a clinical study provide validation for the main part of the model. Overall, the model estimates staff exposure to airborne contamination from surgical smoke and biological material. To address the clinical implication over a long period of time, the systems approach is built upon previous work on multi-scale modeling of surgical flow in a large operating room suite and takes into account human behavior factors.

Studying the Effect of Particulate Matter as SARS-CoV-2 Transmitters

“…Large particulate matter is believed to settle within 2 meters of its source. 8 , 11 To understand how long particulate matter remains airborne in a closed room, an air quality detector (model BR-8C) was used to measure the level of indoor PM 2.5 and PM 10 of Bakhour smoke (Arabian incense) over time. A small natural Bakhour woodchip was burnt for 1 min in charcoal.…”

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

“…In Figures 1-4, we add the status of the procedural activity (top) to put in context and explain the bottom graph that displays a real-time measurement of particle count with an off-the-shelf device Dylos DC 1700, Dylos Corp (Riverside, CA, USA), which was used extensively in our air quality study of surgical suites [17]. Following the work of Setti et al, we assume that airborne diffusion of infected droplets from person to person can occur at a distance greater than two meters [32].…”

“…We specifically developed mathematical and cyber-physical tools to address some of the workflow issues via simulation calibrated on unbiased, real-time, autonomous measurement of clinic performances [13][14][15][16][17][18].…”

“…Respiratory protection devices are used to protect staff in healthcare facilities with various degrees of success [30,31]. We proposed recently a system approach to study the multiple scales of hospital air quality in relation to human factor and described the method in [17].…”

“…A Dylos air quality sensor was attached to the wall of the procedural room at about 1.5 m above the floor: these procedural rooms are relatively small compared to surgery operating rooms. We found in our previous Computational Fluid Dynamics (CFD) calculation and measurement with multiple air sensors [17] that air mixing takes less than a minute to give a relatively uniform SPC in a standard surgical operating room. Due to the smaller size of the GI procedural room and the efficient HVAC system present in them, particle count should have little time lag compared to the source of particles (the staff or the patient).…”