Life Cycle Assessment of Nanofibrous Air Filtering Materials and Respirators

The current spread of COVID-19 pandemics resulted in a surge of a need of respiratory protection devices, including medical facemasks and facepiece respirators. Large amounts of products based on nonwoven filtration material from non-renewable petroleum based plastics (polyethylene) has raised global concerns about excessive environmental impacts of these products. Unfortunately, the replacement of polypropylene nonwoven microfibre based single use masks by the multiple use products did not appear as an effective strategy due to a lower filtration performance, although potentially lower environmental impacts. Nanofibre based filtration devices introduce themselves as potentially more environmentally friendly ones due to a lower overall usage of raw polymer compared to microfibrous ones. We present the LCA modelling of environmental impacts of respiratory protective devices with nanofibrous filter materials and compare those against traditional micro fibrous materials (FFP1 and FFP2 respirator) and medical facemask. Generally, due to a lower mass of nanofibre, these products emerge as a better environmental option, providing similar protection level. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

Are Acoustic Markers of Voice and Speech Signals Affected by Nose-and-Mouth-Covering Respiratory Protective Masks?

BACKGROUND: Worldwide use of nose-and-mouth-covering respiratory protective mask (RPM) has become ubiquitous during COVID19 pandemic. Consequences of wearing RPMs, especially regarding perception and production of spoken communication, are gradually emerging. The present study explored how three prevalent RPMs affect various speech and voice sound properties. METHODS: Pre-recorded sustained [a] vowels and read sentences from 47 subjects were played by a speech production model ('Voice Emitted by Spare Parts', or 'VESPA') in four conditions: without RPM (C1), with disposable surgical mask (C2), with FFP2 mask (C3), and with transparent plastic mask (C4). Differences between C1 and masked conditions were assessed with Dunnett's t test in 26 speech sound properties related to voice production (fundamental frequency, sound intensity level), voice quality (jitter percent, shimmer percent, harmonics-to-noise ratio, smoothed cepstral peak prominence, Acoustic Voice Quality Index), articulation and resonance (first and second formant frequencies, first and second formant bandwidths, spectral center of gravity, spectral standard deviation, spectral skewness, spectral kurtosis, spectral slope, and spectral energy in ten 1-kHz bands from 0 to 10 kHz). RESULTS: C2, C3, and C4 significantly affected 10, 15, and 19 of the acoustic speech markers, respectively. Furthermore, absolute differences between unmasked and masked conditions were largest for C4 and smallest for C2. CONCLUSIONS: All RPMs influenced more or less speech sound properties. However, this influence was least for surgical RPMs and most for plastic RPMs. Surgical RPMs are therefore preferred when spoken communication is priority next to respiratory protection.

Evaluation of the Microbiota and Integrity of Respirators Reused by Health Professionals in a Hospital Environment

The shortage of PFF2, N95, and KN95 respirators and their equivalents for the respiratory protection of the population and health professionals during COVID-19 pandemic has driven the adoption of alternative measures to address the lack of personal protective equipment (PPE). The use of surgical masks, handmade masks, and even the prolonged use of respirators were some of the measures adopted in response to the high demand for these products, and their consequent shortage. In this context, the present study evaluated the microbiota and integrity of reused PFF2 respirators in the central sterile services department of a hospital. Respirators that had been used for 0 h, 12 h, 24 h, and 36 h were sampled for the inoculation and cultivation of fungi and bacteria and the identification of their microbiota. To assess the integrity of the respirators, a filtration efficiency assessment test was conducted of the respirators used for 36 h. The results obtained showed that the microbiota of the respirators comprised commensal fungi and bacteria from the oral and nasal regions of human beings. It was also found that after 36 h of use, the respirators did not demonstrate a decrease in filtration efficiency;that is, they retained their 97% filtration efficiency. Considering the findings regarding the presence and pathogenicity of microorganisms, it is possible that the reuse of respirators for up to 36 h does not harm the health of immunocompetent users. In terms of PPE efficiency, no compromises were evidenced.

Implementation of a successful statewide fit testing program: Breaking down the challenges and barriers

Background: Since its emergence, millions of people have acquired and died from SARS-CoV-2 infections. A key controversy has been how to protect health workers (HWs) when there is ambiguous evidence on the adequacy of personal protective equipment and fit testing. Operationalizing these requirements was very challenging as fit testing had not been routine practice in New South Wales (NSW) Health. Furthermore, it is impractical to fit test 140,000 HWs in the middle of a pandemic. Method(s): A multidisciplinary Respiratory Protection Program (RPP) board was convened with representatives from work health and safety, workplace relations and clinical teams along with legal and union delegates with the aim of providing strategic advice and guidance on implementation, monitoring, and outcomes of RPP. Result(s): Local implementation was led by Infection Prevention and Control and by experienced nurses and work health and safety experts. The program included the more complex aspects of managing HWs who are unable to pass a fit test due to religious, cultural, or medical conditions. During 2021 NSW Health performed 234,499 fit tests on 84,685 HWs with overall, 98% of HWs (n=83210) achieving a fit test pass, demonstrating the success of the program. Conclusion(s): Fit testing is now well established and continues as new staff enter the workforce, new respirators become available as well as repeat testing for those many frontline HWs who were fit tested early in the pandemic. The RPP board is progressing with an evaluation of the program to determine its impact, effectiveness, and sustainability in coming years.Copyright © 2022

Personalized 3D-printed frames to reduce leak from N95 filtering facepiece respirators: a prospective crossover trial in health care workers.

Correctly fitting N95 filtering facepiece respirators (FFRs) have become increasingly important in health care throughout the COVID-19 pandemic. We evaluated the hypothesis that personalized 3-D-printed frames could improve N95 FFRs quantitative fit test pass rates and test scores in health care workers (HCW). HCW were recruited at a tertiary hospital in Adelaide, Australia (ACTRN 12622000388718). A mobile iPhone camera + app was used to produce 3-D scans of volunteers' faces, which were then imported into a software program to produce personalized virtual scaffolds suited to each user's face and their unique anatomical features. These virtual scaffolds were printed on a commercially available 3-D printer, producing plastic (and then silicone-coated, biocompatible) frames that can be fitted inside existing hospital supply N95 FFR. The primary endpoint was improved pass rates on quantitative fit testing - comparing participants wearing an N95 FFR alone (control 1) with participants wearing the frame + N95 FFR (intervention 1). The secondary endpoint was the fit factor (FF) in these groups, and R-COMFI respirator comfort and tolerability survey scores. N = 66 HCW were recruited. The use of intervention 1 increased overall fit test pass rates to 62/66 (93.8%), compared to 27/66 (40.9%) for controls. (OR for pFF pass 20.89 (95%CI: 6.77, 64.48, P < 0.001). Average FF increased, with the use of intervention 1 to 179.0 (95%CI: 164.3,193.7), compared to 85.2 (95%CI: 70.4,100.0) with control 1. Pass rates and FF were improved with intervention 1 compared to control 1 for all stages of the fit-test: bending, talking, side-to-side, and up-down motion. (P < 0.001 all stages). Tolerability and comfort of the frame was evaluated with the validated R-COMFI respirator comfort score, showing improvement with the frame compared to N95 FFR alone (P = 0.006). Personalized 3-D-printed face frames decrease leakage, improve fit testing pass rates and FF, and provide improved comfort compared to the N95 FFR alone. Personalized 3-D-printed face frames represent a rapidly scalable new technology to decrease FFR leakage in HCW and potentially the wider population.

Determinants of nurse's and personal support worker's adherence to facial protective equipment in a community setting during the COVID-19 pandemic in Ontario, Canada: A pilot study.

BACKGROUND: Appropriate and consistent facial protective equipment (FPE) use is critical for preventing respiratory illness transmission. Little is known about FPE adherence by home care providers. The purpose of this study is to adapt an existing facial protection questionnaire and use it to develop an initial understanding of factors influencing home care providers' adherence to FPE during the COVID-19 pandemic. METHODS: A survey was shared with home care providers during Wave 2 of the COVID-19 pandemic in Ontario. Descriptive statistics and logistic regression by FPE adherence were conducted across individual, organizational, and environmental factors. RESULTS: Of the 199 respondents (140 personal support workers; 59 nurses), 71% reported that they always used FPE as required, with greater adherence to masks (89%) than eye protection (73%). The always-adherent reported greater perceived FPE efficacy, knowledge of recommended use and perceived occupational risk, lower education, and not experiencing personal barriers (including difficulty seeing, discomfort, communication challenges). DISCUSSION: Adherence rates were relatively high. In this context, with participants reporting high levels of organizational support, individual-level factors were the significant predictors of adherence. CONCLUSIONS: Initiatives addressing perceived FPE efficacy, knowledge of recommended use, perception of at-work risk, and personal barriers to use may improve FPE adherence.

Patient safety implications of wearing a face mask for prevention in the era of COVID-19 pandemic: a systematic review and consensus recommendations.

In the past, the use of face masks in western countries was essentially limited to occupational health. Now, because of the COVID-19 pandemic, mask-wearing has been recommended as a public health intervention. As potential side effects and some contraindications are emerging, we reviewed the literature to assess the impact of them in daily life on patient safety and to provide appropriate guidelines and recommendations. We performed a systematic review of studies investigating physiological impact, safety, and risk of masks in predefined categories of patients, which have been published in peer-reviewed journals with no time and language restrictions. Given the heterogeneity of studies, results were analyzed thematically. We used PRISMA guidelines to report our findings. Wearing a N95 respirator is more associated with worse side effects than wearing a surgical mask with the following complications: breathing difficulties (reduced FiO2, SpO2, PaO2 increased ETCO2, PaCO2), psychiatric symptoms (panic attacks, anxiety) and skin reactions. These complications are related to the duration of use and/or disease severity. Difficulties in communication is another issue to be considered especially with young children, older person and people with hearing impairments. Even if benefits of wearing face masks exceed the discomfort, it is recommended to take an "air break" after 1-2 h consecutively of mask-wearing. However, well-designed prospective studies are needed. The COVID-19 pandemic could represent a unique opportunity for collecting large amount of real-world data.

Respirators in Healthcare: Material, Design, Regulatory, Environmental, and Economic Considerations for Clinical Efficacy.

Maintaining an ample supply of personal protective equipment continues to be a challenge for the healthcare industry, especially during emergency situations and times of strain on the supply chain. Most critically, healthcare workers exposed to potential airborne hazards require sufficient respiratory protection. Respirators are the only type of personal protective equipment able to provide adequate respiratory protection. However, their ability to shield hazards depends on design, material, proper fit, and environmental conditions. As a result, not all respirators may be adequate for all scenarios. Additionally, factors including user comfort, ease of use, and cost contribute to respirator effectiveness. Therefore, a careful consideration of these parameters is essential for ensuring respiratory protection for those working in the healthcare industry. Here respirator design and material characteristics are reviewed, as well as properties of airborne hazards and potential filtration mechanisms, regulatory standards of governmental agencies, respirator efficacy in the clinical setting, attitude of healthcare personnel toward respiratory protection, and environmental and economic considerations of respirator manufacturing and distribution.

The adequacy of user seal checking for N95 respirators compared to formal fit testing: A multicentred observational study.

OBJECTIVE: The objective of this study was to evaluate the adequacy of the user seal check (USC) in predicting N95 respirator fit. DESIGN: This was a prospective, observational study conducted from May to September 2020. SETTING: The study setting included three private intensive care units (ICUs) in Victoria, Australia. PARTICIPANTS: ICU staff members in three private ICUs in Melbourne and regional Victoria participated in this study. MAIN OUTCOME MEASURES: The main outcome measure is the proportion of participants who passed a USC and subsequently failed fit testing of an N95 respirator. INTERVENTION: Three different respirators were available: two N95 respirator brands and CleanSpace HALO® powered air-purifying respirator. Participants were sequentially tested on N95 respirators followed by powered air-purifying respirators until either successful fit testing or failure of all three respirators. The first N95 tested was based on the availability on the day of testing. The primary outcome was failure rate of fit testing on the first N95 respirator type passing a USC. RESULTS: Of 189 participants, 22 failed USC on both respirators, leaving 167 available for the primary outcome. Fifty-one of 167 (30.5%, 95% confidence interval = 23.7-38.1) failed fit testing on the first respirator type used that had passed a USC. CONCLUSION: USC alone was inadequate in assessing N95 respirator fit and failed to detect inadequate fit in 30% of participants. Mandatory fit testing is essential to ensure adequate respiratory protection against COVID-19 and other airborne pathogens. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12620001193965.

ORGANIZING PNEUMONIA WITH FOREIGN BODY REACTION AS A RESULT OF SODIUM HYDROXIDE AND AMMONIUM SALT VAPOR EXPOSURE

SESSION TITLE: Occupational and Environmental Lung Disease Cases SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/18/2022 12:25 pm - 01:25 pm INTRODUCTION: Sodium hydroxide and ammonium salt vapor exposure are known to cause epithelial necrosis of the tracheobronchial tree, but no pathologic descriptions exist of subsequent inflammatory pneumonitis. CASE PRESENTATION: A 56-year-old man presented to the outpatient clinic with 2 months of progressive scant hemoptysis and dyspnea on exertion. He had a mild smoking history, a history of longstanding stable UC, and had a history significant only for recently performing multiple weeks of cleaning work on a large, enclosed HVAC system with chemicals containing sodium hydroxide and ammonium. He wore no respiratory protection at work. CXR was significant for streaky bilateral lower lobe opacities and CT Chest revealed bilateral basilar ground-glass opacities with a small left pneumothorax. His PFT demonstrated mild restriction with a diffusion defect. Infiltrates persisted after treatment with levofloxacin. A broad autoimmune panel was normal. Bronchoscopy with cryobiopsy showed organizing pneumonia with foreign body reaction. BAL showed primarily mast cells and no organisms were found. Prednisone at 60mg daily with Bactrim prophylaxis and a subsequent prolonged wean was initiated with marked improvement. DISCUSSION: Industrial HVAC cleaning agents are widely used with the proliferation of HVAC systems in the post-COVID world. Other examples exist of prolonged cleaning product use and lung function decline (Svanes et al). Our case report hypothesizes a link between inhalational exposure to sodium hydroxide and ammonium salts with organizing pneumonia with foreign body features, a previously unknown effect. Prednisone led to improvement. CONCLUSIONS: High suspicion for occult pneumonitis should exist when patients present with prolonged exposure to cleaning/noxious chemical vapors exist. Respiratory protection should be emphasized as a public health policy to prevent lung damage among any type of cleaner use including high-skilled (HVAC) cleaners. Reference #1: Advenier, A., & Grandmaison, G. (2022). PULMONARY ACUTE LESIONS AFTER CAUSTIC EXPOSURE. Retrieved 31 March 2022, from https://www.lungdiseasesjournal.com/articles/pulmonary-acute-lesions-after-caustic-exposure.html Reference #2: Svanes, Ø., Bertelsen, R. J., Lygre, S., Carsin, A. E., Antó, J. M., Forsberg, B., García-García, J. M., Gullón, J. A., Heinrich, J., Holm, M., Kogevinas, M., Urrutia, I., Leynaert, B., Moratalla, J. M., Le Moual, N., Lytras, T., Norbäck, D., Nowak, D., Olivieri, M., Pin, I., … Svanes, C. (2018). Cleaning at Home and at Work in Relation to Lung Function Decline and Airway Obstruction. American journal of respiratory and critical care medicine, 197(9), 1157–1163. https://doi.org/10.1164/rccm.201706-1311OC Reference #3: Gorguner, M., & Akgun, M. (2010). Acute inhalation injury. The Eurasian journal of medicine, 42(1), 28–35. https://doi.org/10.5152/eajm.2010.09 DISCLOSURES: no disclosure on file for Ai-Yui Maria Tan;No relevant relationships by Sudha Misra No relevant relationships by Amrik Ray

Tolerability, user acceptance and preference for a novel reusable respirator among health care workers.

BACKGROUND: The CleanSpace Technology Halo respirator combines a clear face mask and a powered air supply, without belts or hoses. Although providing higher protection than other respirators used in health care, user acceptance of this device has not been assessed with validated tools. METHODS: We surveyed healthcare workers (HCWs) within a US medical system using Halo respirators in 2021. Subjects completed 3 surveys over 8 weeks, which included the Respirator Comfort, Wearing Experience, and Function Instrument (R-COMFI), a validated tool to assess respirator tolerability. The survey included additional questions about user acceptability and respirator preference. Responses were evaluated for change over time and for significant predictors. RESULTS: Of 113 HCWs who completed the initial survey (29% response rate), mean ± SD R-COMFI score was 9.1± 5.1, (scale 0-47, lower = more tolerable) and did not change over time (P = .42). Fewer years in healthcare significantly predicted better R-COMFI score (P = .01). Many users preferred Halo in both usual care (45%-52%) and care of patients with COVID-19 (60%-64%). DISCUSSION: Halo respirators received favorable tolerability scores by HCWs, who often preferred them, especially during care of patients with COVID-19. CONCLUSIONS: Given demand for respirator use in health care, the innovative design provides higher protection than other respirators with a favorable user experience.

Dry eye masky syndrome: degree of expression and possibilities of correction

To prevent the spread of COVID-19, to ensure the safety of ourselves and others, personal protective equipment — various types of masks — has firmly entered our daily lives. Purpose to conduct a clinical and sociological study of the severity of the dry eye syndrome in medical personnel and medical students against the background of the use of personal protective equipment and to assess the possibilities of its correction using tear replacement therapy. Materials and methods. 138 medical staff and 149 students were analyzed. A survey was conducted to identify risk factors for the development of the dry eye syndrome. The total tear production was determined using the Schirmer I test at the beginning and after 8 hours of the working day in medical personnel and students before and after a 6-hour lesson. To study the possibility of correcting the dry eye syndrome, students were offered instillations of the tear substitute Gylan 0.18% 3 times a day. At this stage of the study, 2 questionnaires were used to assess the severity of DES symptoms: OSDI and DEQ, Schirmer I test. Results. Most of the study participants noted the constant wearing of masks (86.4 % of doctors and 84.8 % of nurses). At the beginning of the study, 45.1 % of doctors and 51.9 % of nursing staff, 45.6 % of students had indicators of total tear production below the reference values. At the end of working hours, doctors (90.9 %), nurses (88.6 %) and students (69.2 %) showed a decrease in the total tear production of varying severity. The use of a tear substitute made it possible to increase the indicators of total tear production: 10 days after treatment, an increase was observed in 45.7% of cases (but the values were in the range of 10—14 mm), in 31.4 % of cases they reached 15 mm or more and exceeded the initial values (p < 0.05);reduce the symptoms of dry eye: the number of students with DEQ questionnaire syndrome dry eye at the beginning of the study (62.9 %) decreased by 3.2 times. Conclusions: the conducted study allows us to speak about the currently available riskfactorfor the development of the dry eye syndrome: personal respiratory protective equipment has a negative impact on the indicators of total tear production. Appointment of tear replacement therapy allowed to improve thefunctional indicators of tears and quality of life. It is necessary to develop and implement measures aimed at identifying and preventing the development of the dry eye syndrome not only among medical personnel, but also among the population as a whole. © 2022, Real Time LLC. All rights reserved.

Respiratory protection preparedness in critical care healthcare workers: An observational audit of facial hair at a major tertiary hospital in Australia.

BACKGROUND: Facial hair under a tight fitting P2/N95 respirator diminishes respiratory protection. There is limited guidance with respect to the threshold to be clean shaven in readiness to wear N95 respirators. METHODS: We performed a cross sectional audit in late August 2021 to observe whether staff had facial hair that could decrease respiratory protection of tight fitting respirators. The audit was conducted in three critical care areas at a major tertiary public hospital in Australia during a period of moderate-to-high community prevalence of COVID-19. All staff observed had previously successfully completed quantitative fit testing with a clean shaven face in the preceding 12 months. RESULTS: 110 consecutive male critical care staff were observed including thirty staff who were required to wear a N95/P2 respirator at the time. Forty - five percent of male staff observed were not clean shaven in the face seal zone of their respirators. CONCLUSIONS: The readiness to wear a tight-fitting respirator and hence the need to be clean shaven, should be guided by both state and local COVID-19 risk ratings, as well as the specific respiratory biohazard risks present in the clinical area at that time. During periods of significant community transmission of COVID-19, critical care clinical staff should be clean shaven, so they are fit-for-purpose and ready to wear a tight fitting respirator at short notice. Respiratory protection preparedness in critical care healthcare workers: An observational audit of facial hair at a major tertiary hospital in Australia.

Feature, Barrier Face Coverings for Workers.

Face coverings have been recommended for the public and workers to prevent person-to-person transmission of COVID-19. Throughout 2020, guidelines for face coverings recommended multiple layers worn tightly against the face with straps or ear loops. This article briefly describes a new ASTM 3502 Standard Specification for Barrier Face Coverings (BFCs) and the development of performance criteria for workplace BFCs ahead of the Occupational Safety and Health Administration (OSHA) COVID-19 Emergency Temporary Standards (ETS). We also describe a method for comparing the effect on the time to receipt of an infectious dose (ID) of BFCs with varying degrees of inward leakage (personal protection) and outward leakage (source control). The role of BFCs in workplace settings during the pandemic and for exposure to infectious respiratory organisms after the pandemic remains in question. It will be important for occupational health and safety professionals to recognize their limitations in contrast with respiratory protection.

Implementation of a respiratory protection program within healthcare facilities during the COVID-19 pandemic- lessons learned.

The use of fit tested respirators in the workplace is required to protect health workers against airborne pathogens. The COVID-19 pandemic required rapid upscaling of fit testing which was achieved using the framework of a respiratory protection program. Implementing and sustaining such a program in the midst of a pandemic was challenging and required clear direction from a lead agency combined with stakeholder engagement.

Effect of N95 Respirator on Oxygen and Carbon Dioxide Physiologic Response: A Systematic Review and Meta-Analysis.

During the COVID-19 pandemic, N95 respirators were commonly used in many situations. Respiratory problems from prolonged use of respirators were discussed in many studies, which show varied results. From the inconclusive results, the current systematic review and meta-analysis discerned the effects of the N95 respirator by assessing the oxygen and carbon dioxide changes in both high- and low-to-moderate-intensity physical activities in a healthy population. Thirteen studies were identified for inclusion in the study. In high-intensity physical activities, our meta-analysis showed borderline lower oxygen saturation and higher carbon dioxide partial pressure, but oxygen saturation did not change in low-to-moderate physical activity. The use of N95 respirators could statistically affect the physiologic changes of carbon dioxide and oxygen in high-intensity physical activity among healthy participants, but this may not be clinically significant. Some users who have certain health conditions, such as respiratory problems, should be informed of the clinical symptoms related to hypercarbia and hypoxia for the early detection of adverse effects of N95 respirators.

Airborne or Droplet Precautions for Health Workers Treating Coronavirus Disease 2019?

Cases of coronavirus disease 2019 (COVID-19) have been reported in more than 200 countries. Thousands of health workers have been infected, and outbreaks have occurred in hospitals, aged care facilities, and prisons. The World Health Organization (WHO) has issued guidelines for contact and droplet precautions for healthcare workers caring for suspected COVID-19 patients, whereas the US Centers for Disease Control and Prevention (CDC) has initially recommended airborne precautions. The 1- to 2-meter (≈3-6 feet) rule of spatial separation is central to droplet precautions and assumes that large droplets do not travel further than 2 meters (≈6 feet). We aimed to review the evidence for horizontal distance traveled by droplets and the guidelines issued by the WHO, CDC, and European Centre for Disease Prevention and Control on respiratory protection for COVID-19. We found that the evidence base for current guidelines is sparse, and the available data do not support the 1- to 2-meter (≈3-6 feet) rule of spatial separation. Of 10 studies on horizontal droplet distance, 8 showed droplets travel more than 2 meters (≈6 feet), in some cases up to 8 meters (≈26 feet). Several studies of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) support aerosol transmission, and 1 study documented virus at a distance of 4 meters (≈13 feet) from the patient. Moreover, evidence suggests that infections cannot neatly be separated into the dichotomy of droplet versus airborne transmission routes. Available studies also show that SARS-CoV-2 can be detected in the air, and remain viable 3 hours after aerosolization. The weight of combined evidence supports airborne precautions for the occupational health and safety of health workers treating patients with COVID-19.

A Miniaturized Electrostatic Precipitator Respirator Effectively Removes Ambient SARS-CoV-2 Bioaerosols.

The inhalation of ambient SARS-CoV-2-containing bioaerosols leads to infection and pandemic airborne transmission in susceptible populations. Filter-based respirators effectively reduce exposure but complicate normal respiration through breathing zone pressure differentials; therefore, they are impractical for long-term use. OBJECTIVES: We tested the comparative effectiveness of a prototyped miniaturized electrostatic precipitator (mEP) on a filter-based respirator (N95) via the removal of viral bioaerosols from a simulated, inspired air stream. Methods: Each respirator was tested within a 16 L environmental chamber housed within a Class III biological safety cabinet within biosafety level 3 containment. SARS-CoV-2-containing bioaerosols were generated in the chamber, drawn by a vacuum through each respirator, and physical particle removal and viral genomic RNA were measured distal to the breathing zone of each device. MEASUREMENTS AND MAIN RESULTS: The mEP respirator removed particles (96.5 ± 0.4%), approximating efficiencies of the N95 (96.9 ± 0.6%). The mEP respirator similarly decreased SARS-CoV-2 viral RNA (99.792%) when compared to N95 removal (99.942%), as a function of particle removal from the airstream distal to the breathing zone of each respirator. CONCLUSIONS: The mEP respirator approximated the performance of a filter-based N95 respirator for particle removal and viral RNA as a constituent of the SARS-CoV-2 bioaerosols generated for this evaluation. In practice, the mEP respirator could provide equivalent protection from ambient infectious bioaerosols as the N95 respirator without undue pressure drop to the wearer, thereby facilitating its long-term use in an unobstructed breathing configuration.

Impact of the COVID-19 Pandemic on Bedside Medical Education: A Mixed-Methods Study

Background. The COVID-19 pandemic obligated academic medical programs to substantially alter the traditional Internal Medicine (IM) rounding model to decrease risk of inpatient nosocomial viral transmission. Our study aimed to describe how IM rounding practices changed during the COVID-19 pandemic and to understand the impacts of these changes on medical education. Methods. We conducted a two-phase, mixed-methods study of inpatient IM rounding team practices at a large academic hospital in Houston, TX. In the first phase (January-February 2021), we organized and audio-recorded 4 virtual (Zoom) focus groups. Each included 5-6 rounding team members, divided by: attendings;senior residents;interns;and medical and physician assistant students. In the second phase (March-May 2021), we performed 6 direct observations of IM teams during rounds. Two observers systematically recorded variables such as time spent on non-bedside versus bedside rounds, number of each team member type entering patient rooms for bedside teaching, and types of personal protective equipment (PPE) worn. Results. Topics discussed during focus groups included comparisons of rounding team size, rounding duration, physical distancing and PPE use, bedside education, communication methods, and patient safety before and after March 2020. Perceptions of changes in each topic were generally consistent across groups (Table 1). Direct observation data showed that team rounding styles remained diverse in the proportion of rounding time spent in an office versus on the wards, and in the number and types of team members entering patient rooms. IM team members uniformly wore respiratory PPE when entering all patient rooms;use of eye protection varied. Teams spent more total time discussing patients with or suspected to have COVID-19 compared to patients without COVID-19 (median 24 min versus 13 min, p< 0.0001). Conclusion. Our results suggest that the COVID-19 pandemic adversely impacted bedside medical education, even into Spring of 2021. Conclusions from this study can be used to 1) address educational gaps related to COVID-19 pandemic-associated rounding changes and 2) create innovative methods of providing high-quality clinical education that will be minimally impacted by future respiratory virus pandemics.