Laboratory study of a scavenging mask system to evaluate and control airborne pathogens for healthcare workers in the Post Anesthesia Care Unit (PACU) and Intensive Care Unit (ICU)

This laboratory study evaluated the usefulness of a new market available scavenging system (patient mask and filter) in controlling the spread of airborne pathogens by: 1.Develop a laboratory simulation of an infectious patient exhaling a range of respirable bacteria and viruses into a laboratory hood. 2. Compare and contrast capabilities of the market-available scavenging system to reduce and control pathogens in a laboratory setting versus not using a scavenging system. 3. Evaluate the effectiveness of the scavenging system\u27s filter and alternative HEPA filters in capturing these pathogens. A life-like manikin head equipped with a bioaerosol collision nebulizer was set up to simulate a person exhausting pathogenic droplets. The study\u27s hypothesis was tested by using two different scenarios: 1. The scavenging system was used the entire duration of the trial (Case) 2. The scavenging system was not used at all during the trial (Control). The nebulizer used multiple types of respirable pathogens (bacteria and viruses) to represent different size pathogens to evaluate the scavenging system\u27s ability to capture a range of pathogens likely to be found in infectious patients. Pathogens that may escape the scavenging system were captured using liquid impingers, and pathogens inside the scavenging system were captured by the filter that came with the market available mask. A filter flask was used to capture pathogens that broke through the scavenging system supplied filter. The captured pathogens were analyzed and quantified by spread plate analyses for both bacteria and viruses. The filter equipped with the market available scavenging system did not consistently prevent all pathogens from breaking through the filter (p ≥ .05).The HEPA filters in the scavenging mask followed a general trend showing a higher percentage of the smaller viruses passed through the HEPA filter compared to the larger viruses. However, overall the market available scavenging system proved to reduce the exposure to pathogens by 93.2% when exposed to the smallest viruses used (27nm) and as much as 99.9998% for the largest bacteria used (3 μm). Based on this laboratory research, it appears the market available scavenging system may help protect healthcare workers working in the PACU and ICU against airborne pathogen exposure. Further research in clinical trials will help validate these laboratory results