Preclinical validation of occupational and environmental safety of an isolation system for noninvasive ventilation in COVID-19 and other aerosol-transmitted infections

ABSTRACT

Background: The current SARS-CoV-2 pandemic has provoked the collapse of some health systems due to insufficient intensive care unit capacity. The use of continuous positive airway pressure (CPAP) and high-flow nasal oxygen (HFNO) therapies has been limited in consideration of the risk of occupational infection in health-care professionals.

Aims: In preclinical experimental simulations, evaluate occupational and environmental safety of the newly developed isolation system for aerosol-transmitted infections (ISATI).

Method: Simulations were conducted to test ISATI’s capability to isolate aerosolized molecular (caffeine), and biological (SARS-CoV-2 synthetic RNA) markers. Caffeine deposition was analyzed on nitrocellulose sensor discs by proton nuclear magnetic resonance spectroscopy. Synthetic SARS-CoV-2 detection was performed by reverse transcription-polymerase chain reaction.

Results: ISATI demonstrated efficacy in isolating molecular and biological markers within the enclosed environment in simulated conditions of CPAP, HFNO and mechanical ventilation therapy. Neither the molecular marker nor substantial amounts of synthetic SARS-CoV-2 RNA were detected in the surrounding environment, outside ISATI, indicating appropriate occupational safety for health-care professionals.

Conclusion: Aerosolized markers were successfully contained within ISATI in all experimental simulations, offering occupational and environmental protection against the dissemination of aerosolized microparticles under CPAP or HFNO therapy conditions, which are indicated for patients with acute respiratory infections.

KEYWORDS:

• Occupational respiratory infection
• isolation devices respiratory infection
• COVID-19
• influenza
• high-flow oxygen
• continuous positive airway pressure

Acknowledgments

Bhiosupply® provided logistic support and made some essential items used in the experiments available, which were otherwise difficult to purchase considering the conditions imposed by the ongoing pandemic and was the industry that turned ISATI, initially an academic project, into reality. The authors thank the efforts of Bhiosupply® staff: Marcelo Saraiva, Alberto Pereira, Paulo Ferreira and Viviane Linck. The infusion bomb used in the experiments was provided by Bio-data do Brasil, by Regis Claudio da Silva. Experiments performed in hospitals were allowed in the Santa Casa de São Carlos, São Carlos, São Paulo, by Dr. Marcel Domeniconi and Dr. Rafael Luporini, and at Hospital São Rafael, Salvador, Bahia, by Dr. Ana Verena Almeida Mendes. The HFNO machine used in experimets was provided by Dr. Rogério da Hora Passos. Dr. Maria Carolina B. Di Medeiros Leal thanks the Fundação de Apoio à Pesquisa do Estado de São Paulo-FAPESB for the fellowship that enabled her participation in the present study. English editing of the manuscript was performed by Andris K. Walter.

Authorship contributions

Authors that participated in the process of planning, conception of the study design, conducting experiments, acquisition, interpretation and analysis of data: Quadros CA, Leal MCBDM, Baptista-Sobrinho CDA, Nonaka CK, Souza BS, Ferreira AG. Authors that participated in conducting experiments and data acquisition: Milan-Mattos JC, Catai AM, Pires Di Lorenzo VA. All authors participated in writing the manuscript.

Conflict of interest statement

The authors deny the existence of any conflicts of interest.

Declaration of interest

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Data sharing

The data, analytic methods, and study materials will be made available to other researchers by request to the corresponding author.

Reviewer Disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This study was sponsored by the Laboratory of Nuclear Magnetic Resonance, Department of Chemistry, São Carlos Federal University and the Center for Biotechnology and Cell Therapy, São Rafael Hospital, D’Or Institute for Research and Education.