Guidance on the use of respiratory and facial protection equipment

Evaluating Droplet Survivability on Face Masks with X-ray Microtomography

When a person talks, coughs, or sneezes, respiratory droplets are expelled and inevitably land on several surfaces, representing a route for respiratory disease transmission. Here, face masks act as a barrier by obstructing the passage of droplets during exhalation and inhalation. Being constantly exposed to respiratory events and carrying droplet residue, understanding the evaporation and absorption dynamics for tiny droplets on face masks and the fate of viral particle deposition is necessary to analyze the contamination risk. We explore the ideal design for masks from the interaction of mask surfaces with surrogate respiratory droplets by X-ray microscopy and microtomography. We show that the respiratory droplet survivability is significantly reduced in masks with a hydrophilic surface where absorption takes place, leading to a reduction of the postevaporation droplet residue at the mask surface compared with a hydrophobic surface. The results allow us to propose a better mask layer design dependent on wettability, reducing the risk of contamination from respiratory droplets.

COVID-19 in Workplace Settings: Lessons Learned for Occupational Medicine in the UK

This paper addresses lessons learned from the COVID-19 pandemic from a UK Occupational Medicine perspective to permit comparison with other national accounts. In spite of good prior research and statute, the necessary resources to protect workers' health were seriously lacking when the pandemic struck. Weak public health guidance, which did not recognise dominant airborne transmission, was applied to workplaces, leaving workers and others unprotected, especially in respect to Respiratory Protective Equipment (RPE). The Health and Safety Executive (HSE) as regulator was lacking, for example, in not producing guidance to protect HealthCare Workers (HCW) who were amongst the most at risk. The UK COVID-19 Public Inquiry should address shortcomings such as these, but recommendations must be accompanied by robust means to ensure appropriate implementation. These should range from substantial measures to improve indoor air quality, to a permanent pandemic management organization with adequate resources. The enforcing authority has to be obliged to publish more specific workplace guidance than the public health authorities. Occupational medicine as a discipline needs to be better prepared, and hence to assert its responsibility towards high standards of workers' health protection. Future research has to include investigating the best means of mitigation against airborne infection and the management of post-acute covid sequelae.

Instrumental in Surgery: A Narrative Review on Energy-based Surgical Cutting Devices and Surgical Smoke

OBJECTIVE

To provide an informed understanding of existing energy-based surgical cutting technologies and aerosol-generating surgical procedures. We provide a perspective on the future innovation and research potential in this space for the benefit of surgeons, physicians, engineers, and researchers alike.

BACKGROUND

Surgery is a treatment for many medical conditions, the success of which depends on surgical cutting instruments that enable surgeons to conduct surgical procedures for tissue cutting and manipulation. Energy-based surgical cutting tools improve accuracy and limit unnecessary destruction of healthy tissues and cells, but can generate surgical smoke and aerosols, which can be handled using surgical smoke evacuation technology.

METHODS

A narrative review was conducted to explore existing literature describing the history and development of energy-based surgical instruments, their mechanisms of action, aerosol-generating medical procedures, surgical smoke and aerosols from aerosol-generating medical procedures, and the recommended mitigation strategies, as well as research on rapid biological tissue analyzing devices to date.

CONCLUSIONS

Smoke evacuation technology may provide diagnostic information regarding tissue pathology, which could eliminate health concerns and revolutionize surgical accuracy. However, further research into surgical smoke is required to quantify the measurable risk to health it poses, the cutting conditions, under which it is generated and to develop advanced diagnostic approaches using this information.

Does the use of a diving mask adapted for non-invasive ventilation in hypoxemic acute respiratory failure in individuals with and without COVID-19 increase the ratio of arterial oxygen partial pressure to fractional inspired oxygen? A randomized clinical trial

Non-invasive ventilation (NIV) can be used in acute hypoxemic respiratory failure (AHRF); however, verifying the best interface for its use needs to be evaluated in the COVID-19 pandemic scenario. The objective of this study was to evaluate the behavior of the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2 ratio) in patients with AHRF with and without COVID-19 undergoing NIV with the conventional orofacial mask and the adapted diving mask. This is a randomized clinical trial in which patients were allocated into four groups: i) group 1: COVID-19 + adapted mask (n=12); ii) group 2: COVID-19 + conventional orofacial mask (n=12); iii) group 3: non-COVID-19 + adapted mask (n=2); iv) group 4: non-COVID-19 + conventional orofacial mask (n=12). The PaO2/FiO2 ratio was obtained 1, 24, and 48 hours after starting NIV, and the success of NIV was evaluated. This study followed the norms of the Consolidated Standards of Reporting Trials statement and was registered in the Brazilian Registry of Clinical Trials under registration RBR-7xmbgsz. Both the adapted diving mask and the conventional orofacial mask increased the PaO2/FiO2 ratio. The interfaces differed in terms of the PaO2/FiO2 ratio in the first hour [309.66 (11.48) and 275.71 (11.48), respectively] (p=0.042) and 48 hours [365.81 (16.85) and 308.79 (18.86), respectively] (p=0.021). NIV success was 91.7% in groups 1, 2, and 3, and 83.3% in group 4. No adverse effects related to interfaces or NIV were observed. NIV through the conventional orofacial mask interfaces and the adapted diving mask was effective in improving the PaO2/FiO2 ratio; however, the adapted mask presented a better PaO2/FiO2 ratio during use. There was no significant difference between interfaces regarding NIV failure.

Electrospun transparent nanofibers as a next generation face filtration media: A review

The development of fascinating materials with functional properties has revolutionized the humankind with materials comfort, stopped the spreading of diseases, relieving the environmental pollution pressure, economized government research funds, and prolonged their serving life. The outbreak of Coronavirus Disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has triggered great global public health concern. Face masks are crucial tools to impede the spreading of SARS-CoV-2 from human to human. However, current face masks exhibit in a variety of colors (opaque), like blue, black, red, etc., leading to a communication barrier between the doctor and the deaf-mute patient when wearing a mask. High optical transparency filters can be utilized for both personal protection and lip-reading. Thus, shaping face air filter into a transparent appearance is an urgent need. Electrospinning technology, as a mature technology, is commonly used to form nanofiber materials utilizing high electrical voltage. With the alteration of the diameters of nanofibers, and proper material selection, it would be possible to make the transparent face mask. In this article, the research progress in the transparent face air filter is reviewed with emphasis on three parts: mechanism of the electrospinning process and light transmission, preparation of transparent face air filter, and their innovative potential. Through the assessment of classic cases, the benefits and drawbacks of various preparation strategies and products are evaluated, to provide general knowledge for the needs of different application scenarios. In the end, the development directions of transparent face masks in protective gear, particularly their novel functional applications and potential contributions in the prevention and control of the epidemic are also proposed.

Mask-Wearing and Handwashing Behaviors of Chinese Rural Residents during the Pandemic of COVID-19: A Cross-Sectional Survey

OBJECTIVE

To understand mask-wearing and handwashing behaviors of Chinese rural residents during the COVID-19 pandemic and to analyze the associated factors.

METHODS

This study used a multi-stage random sampling method to conduct a cross-sectional questionnaire survey during the period of July to December of 2021, in six counties located in Shandong, Shanxi, and Yunnan provinces representing the eastern, central, and western regions of China, respectively. A total of 3864 villagers were surveyed with a questionnaire, and 3832 valid questionnaires were finally analyzed. Descriptive statistics and logistic regression analysis were used for statistical analysis.

RESULTS

Around ninety-four percent (93.6%) of rural residents reported mask-wearing during the COVID-19 pandemic, but only 44.5% of them could replace masks in time. Multivariate logistic regression analysis showed that those who were female, aged 15-59, had an education level of high school and above, were divorced/widowed, worked as farmers (workers), or were rural residents in Shandong Province were more likely to wear masks. Furthermore, those who were female, aged 15-59, had an education level of high school and above, were unmarried and married, were business and service workers, or were rural residents in Shandong and Shanxi Province replaced masks more timely. Around seventy percent (69.7%) of rural residents reported using soap when washing their hands, but only 38.0% of rural residents could wash their hands properly. Multivariate logistic regression analysis showed that rural residents who were aged 35-59, had an education of high school and above, or lived in Shandong Province and Shanxi Province were more likely to wash their hands with soap. Those who were aged 15-59, had an education of high school and above, worked as farmers (workers), were employees of governmental departments and retirees, were business and service workers, or were students had higher proper handwashing rates.

CONCLUSION

During the COVID-19 pandemic, the proportion of Chinese rural residents wearing masks reached 93.6%, but only 44.5% were able to replace masks in time, gender, age, education level, marital status, occupation, and living place had an impact on mask-wearing. The proportion of Chinese rural residents who could wash hands with soap reached 69.7%, but only 38.0% could wash their hands properly. Age and education level were influencing factors for both washing-hand with soap and proper handwashing.

Filter mask as a new candidate of personal belonging used in cadaver identification – a case report

The case report presents an identification process based on DNA isolated from personal belongings, including a filter mask. In May 2021, an unidentified 65-year-old male corpse was revealed by the city’s outskirts road. Since it was impossible to use material from living relatives for comparative analysis, the samples of personal belongings of the alleged victim were used instead: clippings of the filtering face piece type 2 (FFP2) face mask (parts adhering to the nose and the earlobes, the central part of the mask), swabs from the razor (blade and shaft), toothbrush shaft, and toothbrush filaments clippings. The presented case indicates the need for collecting a wide range of samples for genetic analyses, including filter masks as an alternative item of personal belonging.

Medical masks' and respirators' pattern of use, adverse effects and errors among Portuguese health care professionals during the COVID-19 pandemic: A cross-sectional study

Background

During COVID-19 pandemic, a shortage of surgical masks (Mask) and respirators (Resp) was experienced worldwide. We aimed to assess its pattern of use, adverse effects and user errors by Portuguese health care professionals (HCP).

Methods

A cross-sectional study was conducted through snowball convenience sample, collected by email/ social media to health care organizations. Participants answered an online anonymous survey in March 2021.

Results

Mean age of 3052 respondents was 42.1 years old, 83.6% were female and 77.8% provided direct health care to COVID-19 patients. Mean time of use per shift was 6-8 hours in 40.8% of the participants. 28.0% reported never changing it during their shift. Resp use (vs Mask) was more associated with discomfort (58.2% vs 26.8%), affecting task performance (41.5 vs 18.9%) and communication (55.0 vs 40.9%), dyspnea (36.0 vs 14.4%), skin rash (37.5 vs 19.4%) and headache (37.5 vs 19.4%). Frequent user errors included touching the front while in use (70.1% Mask vs 66.3% Resp) and omitting hand hygiene before (61.8% Mask vs 55.0% Resp) or after use (61.3% Mask vs 57.0% Resp). Average number of errors was higher for Mask (4.3), than for Resp (3.2) (all: P < .001).

Conclusions

Most HCP admitted an extended use of Mask/ Resp. Resp were more prone to adverse effects and Mask more prone to errors. Strategies to reinforce good practices should be considered.

Using a human factors-centric approach to development and testing of a face shield designed for health care workers: A COVID-19 case study for process and outcomes

Background

Face shields are a critical piece of personal protective equipment and their comfort impacts compliant use and thus protectiveness. Optimal design criteria for face shield use in healthcare environments are limited. We attempt to identify factors affecting face shield usability and to test and optimize a face shield for comfort and function in health care settings.

Methods

A broad range of workers in a large health care system were surveyed regarding face shield features and usability. Quantitative and qualitative analysis informed the development of iterative prototypes which were tested against existing shields. Iterative testing and redesign utilized expert insight and feedback from participant focus groups to inform subsequent prototype designs.

Results

From 1,648 responses, 6 key elements were identified: ability to adjust tension, shifting load bearing from the temples, anti-fogging, ventilation, freedom of movement, and durability. Iterative prototypes received consistently excellent feedback based on use in the clinical environment, demonstrating incremental improvement.

Conclusion

We defined elements of face shield design necessary for usability in health care and produced a highly functional face shield that satisfies frontline provider criteria and Emergency Use Authorization standards set by the Food and Drug Administration. Integrating human factors principles into rapid-cycle prototyping for personal protective equipment is feasible and valuable.

State-of-the-Art and Projected Developments of Nanofiber Filter Material for Face Mask Against COVID-19

BACKGROUND

The Covid-19 epidemic was declared a pandemic by the World Health Organization in March 2020. It is difficult to foresee the future length and severity; it may extend to weeks, months, or even years to deplete the energy and resources of the health care facilities and the providers as there is marginal to no pharmacological medication available to treat the Covid-19. Unless an effective pharmacological treatment such as medicines and vaccines is developed and released publicly, wearing protective face masks and protecting personal health and hygiene is merely a choice to avoid the Covid-19 spread. This review summarizes the background knowledge on the Covid-19 disease and currently available face masks for highly infectious disease primary prevention. According to recent studies of Covid-19 prevention, diagnosis, and treatment, nanotechnologists have provided a revolutionary approach that involves both pharmacological and non-pharmacological steps, one of which is the use of nanofibers in facemasks and respirators.

METHODS

Various researches carried out in the field of nanomask and patented reports based on the application of nanomask were reviewed.

CONCLUSION

The most recent developments of nanofibers, including research publications, patents and commercial products in Covid-19 prevention, are extensively reviewed from scientific literature and appropriately represented in this study.

Protective Face Masks: Current Status and Future Trends

Management of the COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has relied in part on the use of personal protective equipment (PPE). Face masks, as a representative example of PPE, have made a particularly significant contribution. However, most commonly used face masks are made of materials lacking inactivation properties against either SARS-CoV-2 or multidrug-resistant bacteria. Therefore, symptomatic and asymptomatic individuals wearing masks can still infect others due to viable microbial loads escaping from the masks. Moreover, microbial contact transmission can occur by touching the mask, and the discarded masks are an increasing source of contaminated biological waste and a serious environmental threat. For this reason, during the current pandemic, many researchers have worked to develop face masks made of advanced materials with intrinsic antimicrobial, self-cleaning, reusable, and/or biodegradable properties, thereby providing extra protection against pathogens in a sustainable manner. To overview this segment of the remarkable efforts against COVID-19, this review describes the different types of commercialized face masks, their main fabrication methods and treatments, and the progress achieved in face mask development.

Adapted full-face snorkel masks as an alternative for COVID-19 personal protection during aerosol generating procedures in South Africa: A multi-centre, non-blinded in-situ simulation study

INTRODUCTION

SARS-CoV-2 has resulted in increased worldwide demand for personal protective equipment (PPE). With pressure from ongoing epidemic and endemic episodes, we assessed an adapted snorkel mask that provides full-face protection for healthcare workers (HCWs), particularly during aerosol-generating procedures. These masks have a custom-made adaptor which allows the fitment of standard medical respiratory filters. The aim of this study was to evaluate the fit, seal and clinical usability of these masks.

METHODS

This multicentre, non-blinded in-situ simulation study recruited fifty-two HCWs to don and doff the adapted snorkel mask. Negative pressure seal checks and a qualitative fit test were performed. The HCWs completed intubation and extubation of a manikin in a university skills training laboratory, followed by a web-based questionnaire on the clinical usability of the masks.

RESULTS

Whilst fit and usability data were generally satisfactory, two of the 52 participants (3.8%) felt that the mask did not span the correct distance from the nose to the chin, and 3 of 34 participants (8.8%) who underwent qualitative testing with a Bitrex test failed. The majority of users reported no fogging, humidity or irritation. It was reportedly easy to speak while wearing the mask, although some participants perceived that they were not always understood. Twenty-one participants (40%) experienced a subjective physiological effect from wearing the mask; most commonly a sensation of shortness of breath.

DISCUSSION

A fit-tested modified full-face snorkel mask may offer benefit as a substitute for N95 respirators and face shields. It is, however, important to properly select the correct mask based on size, fit testing, quality of the three-dimensional (3D) printed parts and respiratory filter to be used. Additionally, HCWs should be trained in the use of the mask, and each mask should be used by a single HCW and not shared.

Biodegradable and multifunctional surgical face masks: A brief review on demands during COVID-19 pandemic, recent developments, and future perspectives

Providing the greater public with the current coronavirus (SARS-CoV-2) vaccines is time-consuming and research-intensive; intermediately, some essential ways to reduce the transmission include social distancing, personal hygiene, testing, contact tracing, and universal masking. The data suggests that universal masking, especially using multilayer surgical face masks, offers a powerful efficacy for indoor places. These layers have different functions including antiviral/antibacterial, fluid barrier, particulate and bacterial filtration, and fit and comfort. However, universal masking poses a serious environmental threat since billions of them are disposed on a daily basis; the current coronavirus disease (COVID-19) has put such demands and consequences in perspective. This review focuses on surgical face mask structures and classifications, their impact on our environment, some of their desirable functionalities, and the recent developments around their biodegradability. The authors believe that this review provides an insight into the fabrication and deployment of effective surgical face masks, and it discusses the utilization of multifunctional structures along with biodegradable materials to deal with future demands in a more eco-friendly fashion.

COVID-19 in Ophthalmology. Current Disease Status and Challenges during Clinical Practice

Purpose: The novel coronavirus disease 2019 (COVID-19) has raised a global public health concern. The purpose of this review is to summarize the evidence currently available on COVID-19 for its ocular implications and manifestations from both pathogenetic and clinical standpoints. Methods: For this narrative review, more than 100 relevant scientific articles were considered from various databases (PubMed, Google Scholar, and Science Direct) using keywords such as coronavirus outbreak, COVID-19, ophthalmology, ocular symptoms. Results:Daily healthcare both from patient and physician perspective, as well as on some guidelines regarding prevention and management have dramatically changed over the last few months. Although COVID-19 infection mainly affects the respiratory system as well as the gastrointestinal, cardiovascular, and urinary systems, it may cause a wide spectrum of ocular manifestations. Various challenges have to be faced to minimize exposure for both patients and physicians. Conclusion:The risk of COVID-19 infection should be considered and medical care should be prioritized for urgent cases. Appropriate management for patients with chronic cases that may result in adverse outcomes should not be neglected, while patients that can be monitored remotely should be identified.

Infection Control in the Era of COVID-19: A Narrative Review

COVID-19 quickly became a pandemic causing millions of infections and mortalities. It required real-time adjustments to healthcare systems and infection prevention and control (IPC) measures to limit the spread and protect healthcare providers and hospitalized patients. IPC guidelines were adopted and developed based on experience gained during the MERS-CoV and SARS-CoV outbreaks. The aim of this narrative review is to summarize current evidence on IPC in healthcare settings and patients with COVID-19 to prevent nosocomial infections during the actual pandemic. A search was run on PubMed using the terms (‘COVID-19’ [Mesh]) AND (‘Infection Control’ [Mesh]) between 2019 and 2021. We identified 86 studies that were in accordance with our aim and summarized them under certain themes as they related to COVID-19 infection control measures. All the guidelines recommend early diagnosis and rapid isolation of COVID-19 patients. The necessary precautions should be taken comprising the whole process, starting with an infectious disease plan, administrative and engineering controls, triage, and PPE training. Guidelines should target modes of transmission, droplet, aerosol, and oral–fecal, while recommending control precautions. Healthcare facilities must promptly implement a multidisciplinary defense system to combat the outbreak.

Endoscopy training in COVID-19: Challenges and hope for a better age

The COVID-19 pandemic is a unique challenge that has disrupted endoscopy training. Initial infection control measures aimed at protecting patients and staff meant nonessential endoscopic activity was suspended in many countries. The decrease in elective caseload from the pandemic also reduced training numbers during this period. While hands-on training took a backseat, more efforts were directed to didactic training of cognitive competencies. We review the literature describing the impact of COVID-19 on endoscopy training and summarize key measures aimed at mitigating this effect. These include leveraging on web-based didactic material and video-conferences, increased use of simulation and models to hone technical competencies, and a shift in focus from numbers-based accreditation to competency-based accreditation. While COVID-19 was hoped to be short-lived, it is clear the impact is long-lasting. Hence, it is crucial for training programs to take stock of how endoscopy training is evolving and use this opportunity to implement new paradigms into their endoscopic training curricula. COVID-19 might just be the catalyst that transforms endoscopy training into a new digital era.

An antiviral trap made of protein nanofibrils and iron oxyhydroxide nanoparticles

Minimizing the spread of viruses in the environment is the first defence line when fighting outbreaks and pandemics, but the current COVID-19 pandemic demonstrates how difficult this is on a global scale, particularly in a sustainable and environmentally friendly way. Here we introduce and develop a sustainable and biodegradable antiviral filtration membrane composed of amyloid nanofibrils made from food-grade milk proteins and iron oxyhydroxide nanoparticles synthesized in situ from iron salts by simple pH tuning. Thus, all the membrane components are made of environmentally friendly, non-toxic and widely available materials. The membrane has outstanding efficacy against a broad range of viruses, which include enveloped, non-enveloped, airborne and waterborne viruses, such as SARS-CoV-2, H1N1 (the influenza A virus strain responsible for the swine flu pandemic in 2009) and enterovirus 71 (a non-enveloped virus resistant to harsh conditions, such as highly acidic pH), which highlights a possible role in fighting the current and future viral outbreaks and pandemics.

The psychological impact of the Coronavirus emergency on physicians and nurses: an Italian observational study

Background and aim of the work:

The Coronavirus has put a strain on the response capacity of health systems and there are various psychological effects on health workers.

Aim of the study:

To investigate the psychological impact of the coronavirus emergency on physicians and nurses.

Methods:

A study was conducted on a sample of nurses and physicians (n=770), who were asked to fill in a questionnaire investigating physical and psychological problems. It also included the IES (Impact Event Scale), STAI (State Trait Anxiety Inventory) scale and BDI (Beck Depression Inventory).

Results:

87.7% of the sample was represented by nurses (n=675), 12.3% (n=95) by physicians. 52.3% (n=403). Among the psychological symptoms, stress (76.2%; n=587), anxiety (59.4%; n=457) and depression (11.8%) prevailed and only 3.9% of the healthcare personnel sought help from a psychologist. The total score of the IES-R scale was 3.47. A significant association emerged between exposure and the risk of contagion (p-value = 0.003), stress was more present among nurses than among physicians (77.5% vs. 67.4%; p = 0.003). Among physical symptoms, headache (52.2%; n=402) and pressure injuries (24.8% n= 191) prevailed.

Conclusions:

The results of the study show that mental health monitoring of health workers, who are at risk of developing major psychological disorders, is a priority.

Respiratory Protection Effect of Ear-loop-type KF94 Masks according to the Wearing Method in COVID-19 Pandemic: a Randomized, Open-label Study

BACKGROUND

Ear-loop-type Korean Filter 94 masks (KF94 masks, equivalent to the N95 and FFP2) are broadly used in health care settings in Korea for the coronavirus disease 2019 pandemic.

METHODS

A prospective randomized open-label study was designed to identify differences in the fitting performance between mask wearing methods in three different types of KF94 mask with ear loops between January to March 2021. General-fitting involved wearing an ear-loop-type KF94 mask, and tight-fitting involved wearing a mask aided by a clip connecting the ear loops. Each of the 30 participants wore three types of masks according to a randomly assigned order in both methods and performed a total of six quantitative fit tests (QNFTs) according to the occupational safety and health administration protocol.

RESULTS

All fit factors (FFs) measured by the QNFT were significantly higher for tight-fitting method with the clip in all KF94 masks (P < 0.001). However, the total FFs were very low, with a median (interquartile range) of 6 (3-23) and 29 (9-116) for general-fitting and tight-fitting, respectively. When wearing tightly, the horizontal 3-fold type mask with adjustable ear-loop length had the highest FF, with a median of 125, and the QNFT pass rate (FF ≥ 100) increased significantly from 4 (13%) to 18 (60%).

CONCLUSION

Even with sufficient filter efficiency, ear-loop-type-KF94 masks do not provide adequate protection. However, in relatively low-risk environments, wearing a face-seal adjustable KF94 mask and tight wearing with a clip can improve respiratory protection for healthcare workers.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04794556.

Serologic Surveillance and Phylogenetic Analysis of SARS-CoV-2 Infection Among Hospital Health Care Workers

IMPORTANCE

It is unclear when, where, and by whom health care workers (HCWs) working in hospitals are infected with SARS-CoV-2.

OBJECTIVE

To determine how often and in what manner nosocomial SARS-CoV-2 infection occurs in HCW groups with varying exposure to patients with COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study comprised 4 weekly measurements of SARS-CoV-2-specific antibodies and collection of questionnaires from March 23 to June 25, 2020, combined with phylogenetic and epidemiologic transmission analyses at 2 university hospitals in the Netherlands. Included individuals were HCWs working in patient care for those with COVID-19, HCWs working in patient care for those without COVID-19, and HCWs not working in patient care. Data were analyzed from August through December 2020.

EXPOSURES

Varying work-related exposure to patients infected with SARS-CoV-2.

MAIN OUTCOMES AND MEASURES

The cumulative incidence of and time to SARS-CoV-2 infection, defined as the presence of SARS-CoV-2-specific antibodies in blood samples, were measured.

RESULTS

Among 801 HCWs, there were 439 HCWs working in patient care for those with COVID-19, 164 HCWs working in patient care for those without COVID-19, and 198 HCWs not working in patient care. There were 580 (72.4%) women, and the median (interquartile range) age was 36 (29-50) years. The incidence of SARS-CoV-2 was increased among HCWs working in patient care for those with COVID-19 (54 HCWs [13.2%; 95% CI, 9.9%-16.4%]) compared with HCWs working in patient care for those without COVID-19 (11 HCWs [6.7%; 95% CI, 2.8%-10.5%]; hazard ratio [HR], 2.25; 95% CI, 1.17-4.30) and HCWs not working in patient care (7 HCWs [3.6%; 95% CI, 0.9%-6.1%]; HR, 3.92; 95% CI, 1.79-8.62). Among HCWs caring for patients with COVID-19, SARS-CoV-2 cumulative incidence was increased among HCWs working on COVID-19 wards (32 of 134 HCWs [25.7%; 95% CI, 17.6%-33.1%]) compared with HCWs working on intensive care units (13 of 186 HCWs [7.1%; 95% CI, 3.3%-10.7%]; HR, 3.64; 95% CI, 1.91-6.94), and HCWs working in emergency departments (7 of 102 HCWs [8.0%; 95% CI, 2.5%-13.1%]; HR, 3.29; 95% CI, 1.52-7.14). Epidemiologic data combined with phylogenetic analyses on COVID-19 wards identified 3 potential HCW-to-HCW transmission clusters. No patient-to-HCW transmission clusters could be identified in transmission analyses.

CONCLUSIONS AND RELEVANCE

This study found that HCWs working on COVID-19 wards were at increased risk for nosocomial SARS-CoV-2 infection with an important role for HCW-to-HCW transmission. These findings suggest that infection among HCWs deserves more consideration in infection prevention practice.

How much COVID-19 face protections influence speech intelligibility in classrooms?

The ongoing pandemic caused by the COVID-19 virus is challenging many aspects of daily life. Several personal protective devices have become essential in our lives. Face protections are mostly used in order to stop the air aerosol coming out of our mouths. Nevertheless, this fact may also have a negative effect on speech transmission both in outdoor and indoor spaces. After a severe lockdown, classes have now started again. The adoption of face protection by teachers is either recommended or mandatory even though this is affecting speech intelligibility and thus students' comprehension. This study aims to understand how protections may affect the speech transmission in classrooms and how this could be influenced by the several typologies of face protections. An experimental campaign was conducted in a classroom in two different reverberant conditions, measuring and comparing the variation in speech transmission and sound pressure level at different receiver positions. Furthermore, a microphone array was used to investigate the distribution of the indoor sound field, depending on the sound source. Results clearly show how different types of personal protection equipment do affect speech transmission and sound pressure level especially at mid-high frequency and that the source emission lobes vary when wearing certain types of personal devices.

Protective Measures against COVID-19: Dental Practice and Infection Control

The onset of the Coronavirus 2019 (COVID-19) pandemic has challenged the worldwide healthcare sector, including dentistry. The highly infectious nature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus and risk of transmission through aerosol generating procedures has profoundly impacted the delivery of dental care services globally. As dental practices with renewed infection control strategies and preventive measures are re-opening in the "new normal" period, it is the responsibility of healthcare professionals to constantly analyze new data and limit the spread of COVID-19 in dental care settings. In the light of new variants of SARS-CoV-2 rapidly emerging in different geographic locations, there is an urgent need to comply more than ever with the rigorous public health measures to mitigate COVID-19 transmission. The aim of this article is to provide dental clinicians with essential information regarding the spread of SARS-CoV-2 virus and protective measures against COVID-19 transmission in dental facilities. We complied and provided guidance and standard protocols recommended by credible national and international organizations. This review will serve as an aid to navigating through this unprecedented time with ease. Here we reviewed the available literature recommended for the best current practices that must be taken for a dental office to function safely and successfully.

Behavior in the use of face masks in the context of COVID-19

OBJECTIVES

Investigation of potential erroneous behavior in the general public's use of face masks during the COVID-19 pandemic.

DESIGN

We conducted a naturalistic observational study in the period from April to June 2020.

SAMPLE

In two western Austrian provinces, a total of 2080 persons were observed in front of 24 grocery stores.

MEASUREMENT

The frequencies and types of erroneous behavior in the use of face masks were collected using a standardized observation form.

RESULTS

A total of 2080 persons were observed. Almost one-third of all observations (n = 648; 31.2%) showed erroneous behavior before positioning the face masks. Another 935 (45.0%) persons touched the face mask front during the adjustment via mouth and nose, 501 (24.1%) persons touched the face mask front in the period after the adjustment. A total of 116 (5.6%) persons showed erroneous behavior in each sequence of the observation unit. Overall, almost half of all people observed showed at least one erroneous behavior within the observation period.

CONCLUSIONS

The behavior of the general public in handling face masks is highly error-prone. Decision makers must increasingly provide accompanying information and educational measures in order to encourage the population at risk to use face masks correctly.

Study of the Pathogen Inactivation Mechanism in Salt-Coated Filters

As COVID-19 exemplifies, respiratory diseases transmitted through aerosols or droplets are global threats to public health, and respiratory protection measures are essential first lines of infection prevention and control. However, common face masks are single use and can cause cross-infection due to the accumulated infectious pathogens. We developed salt-based formulations to coat membrane fibers to fabricate antimicrobial filters. Here, we report a mechanistic study on salt-induced pathogen inactivation. The salt recrystallization following aerosol exposure was characterized over time on sodium chloride (NaCl), potassium sulfate (K₂SO₄), and potassium chloride (KCl) powders and coatings, which revealed that NaCl and KCl start to recrystallize within 5 min and K₂SO₄ within 15 min. The inactivation kinetics observed for the H1N1 influenza virus and Klebsiella pneumoniae matched the salt recrystallization well, which was identified as the main destabilizing mechanism. Additionally, the salt-coated filters were prepared with different methods (with and without a vacuum process), which led to salt coatings with different morphologies for diverse applications. Finally, the salt-coated filters caused a loss of pathogen viability independent of transmission mode (aerosols or droplets), against both DI water and artificial saliva suspensions. Overall, these findings increase our understanding of the salt-recrystallization-based technology to develop highly versatile antimicrobial filters.

Reducing the risk of infection to patients and staff during gynaecological outpatient and ambulatory appointments

This chapter explores ways to reduce the risk of severe acute respiratory syndrome coronavirus-2 transmission to women and staff within gynaecology outpatient clinics. The likely routes of transmission are discussed, namely through droplets, aerosols and fomites. Using the 'hierarchy of control' categories, elimination, substitution, engineering, administration and personal protective equipment, practical strategies for modifying virus exposure are presented. The management of specific clinical conditions are reviewed based on advice prepared by the specialist societies in conjunction with each other and the Royal College of Obstetricians and Gynaecologists. The need to maintain at least a minimal level of gynaecological services is recognised and that this should provide safe, equitable and effective care. Ways to reduce clinic attendance are discussed with the substitution of face-to-face with remote consultations and when this is relevant. Current recommendations for ambulatory procedures, which include colposcopy and hysteroscopy, are considered so that best use is made of reduced resources.

Efficacy of Face Masks Used in Uganda: A Laboratory-Based Inquiry during the COVID-19 Pandemic

With shortages of face masks being reported worldwide, it is critical to consider alternatives to commercially manufactured face masks. This study aimed to test and compare the efficacy of various makes of locally made or homemade cloth face masks obtained from face-mask vendors in Kampala, Uganda, during the COVID-19 pandemic. The testing was performed to assess the bacterial filtration efficiency (BFE), breathability, distance-dependent fitness, and reusability of the locally made or homemade cloth face masks, while considering the most commonly used non-published face-mask decontamination approaches in Uganda. During laboratory experimentation, modified protocols from various face-mask testing organizations were adopted. Ten different face-mask types were experimented upon; each face-mask type was tested four times for every single test, except for the decontamination protocols involving washing where KN95 and surgical face masks were not included. Among the locally made or homemade cloth face masks, the double-layered cloth face masks (described as F) had better BFE and distance-dependent fitness characteristics, they could be reused, and had good breathability, than the other locally made or homemade cloth face masks. Despite these good qualities, the certainty of these face masks protecting wearers against COVID-19 remains subject to viral filtration efficiency testing.

The Perils of Covid-19 for Otorhinolaryngologists: An Overview

Covid-19 symptoms are commonly seen in Otorhinolaryngology clinics on a daily basis. This article provides a brief review of the current knowledge regarding SARS Cov-2 including disease transmission, clinical characteristics and occupational hazard. The article focuses on the adequate precautions needed for Otorhinolaryngologists. We, being involved in the frequent manipulation of the aero-digestive tract containing a high viral load carry the biggest threat of an occupational hazard. We should be aware of utmost importance of effective use of full or enhanced Personal Protective Equipment during diagnostic and therapeutic procedures.

Implications of COVID-19 for Ophthalmologists

PURPOSE

To describe and explain the implications of coronavirus disease 2019 (COVID-19) for ophthalmologists considering the rapid developments in our understanding of the virology, transmission, and ocular involvement.

DESIGN

Evidence-based perspective.

METHODS

Review and synthesis of pertinent literature.

RESULTS

Retrospective studies highlight that <1% of patients display COVID-19-related conjunctivitis. However, prospective studies suggest the rate is higher (~6%). Viral RNA has been identified in tears and conjunctival secretions in patients with active conjunctivitis as well as asymptomatic cases. Overall, conjunctival swabs are positive in 2.5%. Samples taken earlier in the disease course are more likely to demonstrate positive virus. Viral transmission through ocular tissues has not been substantiated. Ophthalmologists are in the high-risk category for COVID-19 infection for several reasons: high-volume clinics, close proximity with patients, equipment-intense clinics, and direct contact with patients' conjunctival mucosal surfaces. COVID-19 is predominantly contracted through direct or airborne transmission by inhalation of respiratory droplets. Evidence that aerosol transmission occurs is increasing in particularly prolonged exposure to high concentrations in a relatively closed environment. Based on the current evidence, ophthalmologists should consider measures that include social distancing, wearing masks, sterilization techniques, and managing clinic volumes.

CONCLUSIONS

A major challenge to containing COVID-19 is that many infected people are asymptomatic. Droplet spread, contaminated environmental surfaces, and shared medical devices are areas that require management by ophthalmologists. More studies are required to explore the role of the conjunctiva and ocular tissues in the transmission of disease.

Tracheostomy in the COVID19 Patients: Our Experience in 12 Cases

The incidence of tracheostomy has been significantly increased with the increase of patients admitted to the intensive care units. Looking into the literature, there have been various protocols proposed in the past for tracheostomy in COVID 19 patients. In the present case series, we have presented our experience of surgical tracheostomy in COVID 19 patients. It is a retrospective case series consisting of 12 COVID 19 patients who underwent tracheostomy from April 2020 to October 2020. We have discussed the tracheostomy in COVID 19 patients with references to their respective indication, location, the procedure, postoperative care and clinical outcomes. Of 12 patients, 6 were operated in the COVID ICU and 6 were operated in the COVID OT. The average duration of the intubation was 4 days (range 3–7 days). The average period of weaning was found to be 65 h (range 48 h 80 h). Of 4 patients associated with comorbidities, two had died 48 h after the surgery. The Primary indication of the tracheostomy can be made flexible based on the infrastructure of the hospital to accommodate increased patient load in a developing country like India. The location and surgical approach does not significantly affect the clinical outcomes of tracheostomy, and it can be safely performed in ICU/OT with adequate ventilation. Irrespective of the COVID status of the patients, Personal Protective Equipment (PPE) can ensure adequate protection to the health care personals preventing the spread of infection.

Review of guidelines and recommendations from 17 countries highlights the challenges that clinicians face caring for neonates born to mothers with COVID-19

AIM

This review examined how applicable national and regional clinical practice guidelines and recommendations for managing neonates born to mothers with COVID-19 mothers were to the evolving pandemic.

METHODS

A systematic search and review identified 20 guidelines and recommendations that had been published by May 25, 2020. We analysed documents from 17 countries: Australia, Brazil, Canada, China, France, India, Italy, Japan, Saudi Arabia, Singapore, South Africa, South Korea, Spain, Sweden, Switzerland, the UK and the United States.

RESULTS

The documents were based on expert consensus with limited evidence and were of variable, low methodological rigour. Most did not provide recommendations for delivery methods or managing symptomatic infants. None provided recommendations for post-discharge assimilation of potentially infected infants into the community. The majority encouraged keeping mothers and infants together, subject to infection control measures, but one-third recommended separation. Although breastfeeding or using breastmilk was widely encouraged, two countries specifically prohibited this.

CONCLUSION

The guidelines and recommendations for managing infants affected by COVID-19 were of low, variable quality and may be unsustainable. It is important that transmission risks are not increased when new information is incorporated into clinical recommendations. Practice guidelines should emphasise the extent of uncertainty and clearly define gaps in the evidence.

Procedures in COVID-19 Patients: Part-I

The number of cases with novel coronavirus disease-2019 (COVID-19) infection is increasing every day in the world, and India contributes a substantial proportion of this burden. Critical care specialists have accepted the challenges associated with the COVID-19 pandemic and are frontline warriors in this war. They have worked hard in streamlining workflow isolation of positive patients, clinical management of critically ill patients, and infection prevention practices. With no end in sight for this pandemic, intensive care unit (ICU) practitioners, hospital administrators, and policy makers have to join hands to prepare for the surge in critical care bed capacity. In this position article, we offer several suggestions on important interventions to the ICU practitioners for better management of critically ill patients. This position article highlights key interventions for COVID-19 treatment and covers several important issues such as endotracheal intubation and tracheostomy (surgical vs PCT), nebulization, bronchoscopy, and invasive procedures such as central venous catheters, arterial lines, and HD catheters. How to cite this article: Pande RK, Bhalla A, SN Myatra, Yaddanpuddi LN, Gupta S, Sahoo TK, et al. Procedures in COVID-19 Patients: Part-I. Indian J Crit Care Med 2020;24(Suppl 5):S263-S271.

Triaging of respiratory protective equipment on the assumed risk of SARS-CoV-2 aerosol exposure in patient-facing healthcare workers delivering secondary care: a rapid review

OBJECTIVES

In patient-facing healthcare workers delivering secondary care, what is the evidence behind UK Government personal protective equipment (PPE) guidance on surgical masks versus respirators for SARS-CoV-2 protection?

DESIGN

Two independent reviewers performed a rapid review. Appraisal was performed using Critical Appraisal Skills Programme checklists and Grading of Recommendations, Assessment, Development and Evaluations methodology. Results were synthesised by comparison of findings and appraisals.

DATA SOURCES

MEDLINE, Google Scholar, UK Government COVID-19 website and grey literature.

ELIGIBILITY CRITERIA

Studies published on any date containing primary data comparing surgical facemasks and respirators specific to SARS-CoV-2, and studies underpinning UK Government PPE guidance, were included.

RESULTS

Of 30 identified, only 3 laboratory studies of 14 different respirators and 12 surgical facemasks were found. In all three, respirators were significantly more effective than facemasks when comparing protection factors, reduction factors, filter penetrations, total inspiratory leakages at differing particle sizes, mean inspiratory flows and breathing rates. Tests included live viruses and inert particles on dummies and humans. In the six clinical studies (6502 participants) included the only statistically significant result found continuous use of respirators more effective in clinical respiratory illness compared with targeted use or surgical facemasks. There was no consistent definition of 'exposure' to determine the efficacy of respiratory protective equipment (RPE). It is difficult to define 'safe'.

CONCLUSIONS

There is a paucity of evidence on the comparison of facemasks and respirators specific to SARS-CoV-2, and poor-quality evidence in other contexts. The use of surrogates results in extrapolation of non-SARS-CoV-2 specific data to guide UK Government PPE guidance. The appropriateness of this is unknown given the uncertainty over the transmission of SARS-CoV-2.This means that the evidence base for UK Government PPE guidelines is not based on SARS-CoV-2 and requires generalisation from low-quality evidence of other pathogens/particles. There is a paucity of high-quality evidence regarding the efficacy of RPE specific to SARS-CoV-2. UK Government PPE guidelines are underpinned by the assumption of droplet transmission of SARS-CoV-2.These factors suggest that the triaging of filtering face piece class 3 respirators might increase the risk of COVID-19 faced by some.

COVID-19: Adapting to change, general surgery at a district general hospital in the United Kingdom

The Coronavirus pandemic has caused major change across the world and in the National Health Service. In order to cope and help limit contagion, numerous institutions recognised the need to adjust clinical practice quickly yet safely. In this paper, we aim to describe the changes implemented in a general surgery department at a district general hospital in the United Kingdom. Across the surgical specialties, frameworks, protocols and guidelines have been established locally and nationally. The aerosol generating procedures involved in general surgery required us to alter our daily activities. Modifications to patient management were necessary to try and reduce viral spread. Staff wellbeing was heavily promoted in order to help maintain the frontline workforce. A holistic approach was required.

The role of fit testing N95/FFP2/FFP3 masks: a narrative review

For healthcare workers performing aerosol-generating procedures during the COVID-19 pandemic, well fitted filtering facepiece respirators, for example, N95/FFP2 or N99/FFP3 masks, are recommended as part of personal protective equipment. In this review, we evaluate the role of fit checking and fit testing of respirators, in addition to airborne protection provided by respirators. Filtering facepiece respirators are made of material with sufficient high filter capacity to protect against airborne respiratory viruses. Adequate viral protection can only be provided by respirators that properly fit the wearer's facial characteristics. Initial fit pass rates vary between 40% and 90% and are especially low in female and in Asian healthcare workers. Fit testing is recommended to ensure a proper fit of respirators for the individual healthcare worker so that alternative respirators can be selected if required. Although fit testing is required to comply with respirator standards, it is not performed consistently within all healthcare settings. Fit checking (a self-test) is recommended every time a healthcare worker dons a respirator, but is unreliable in detecting proper fit or leak. Additionally, fit testing has a high educational value and as such is best performed as part of a hospital respiratory protection programme. Whether fit checking alone, as opposed to fit tested and fit checked respirators, provides adequate airborne protection against aerosols containing the SARS-CoV-2 virus and other respiratory viruses remains unknown. While fit testing undoubtedly incurs additional costs, it is still recommended, not only to protect healthcare workers but also as it may reduce overall healthcare cost when considering the potential costs of sickness leave and the associated legal costs of compensation.

Advances in Antiviral Material Development

The rise in human pandemics demands prudent approaches in antiviral material development for disease prevention and treatment via effective protective equipment and therapeutic strategy. However, the current state of the antiviral materials research is predominantly aligned towards drug development and its related areas, catering to the field of pharmaceutical technology. This review distinguishes the research advances in terms of innovative materials exhibiting antiviral activities that take advantage of fast-developing nanotechnology and biopolymer technology. Essential concepts of antiviral principles and underlying mechanisms are illustrated, followed with detailed descriptions of novel antiviral materials including inorganic nanomaterials, organic nanomaterials and biopolymers. The biomedical applications of the antiviral materials are also elaborated based on the specific categorization. Challenges and future prospects are discussed to facilitate the research and development of protective solutions and curative treatments.

The use of personal protective equipment in clinical ophthalmology during corona virus disease-2019: a review of international guidelines and literature

PURPOSE OF REVIEW

The use of nonpharmaceutical interventions can prevent viral spread in COVID-19 pandemic and PPE forms a crucial part of this strategy. However, there are discrepancies in existing guidelines and a lack of consensus among ophthalmic communities. This review aims to identify general consensus and provides recommendation of PPE for most common ophthalmological scenarios. With a global shortage of PPE, extended use and reuse strategies are also discussed.

RECENT FINDINGS

In this review, guidelines and resources were selected, based on a three-tier process. The first-tier resources were from international infection control organizations. The second-tier resources were from ophthalmological professional associations and colleges. The third-tier resources involved a PubMed search using the keywords 'COVID-19; coronavirus; personal protective equipment' performed on 1 May 2020. Non-English guidelines and literatures were excluded.

SUMMARY

On the basis of our methodology, we included a total of 30 documents, including 5 resources from tier 1, 14 resources from tier 2 and 15 from tier 3. Different levels of protection are necessary. Whenever performing an aerosol generating procedure, maximum protection should be ensured, this includes FFP3 respirator, fluid resistant gown, goggles or face-shield and disposable gloves. Similar protection should be used for handling COVID-19-positive/suspected case but the use of FFP2 respirator is acceptable. During routine outpatient clinic in cases of negative triage, it is recommended to use ASTM III surgical mask, plastic apron, disposable gloves and eye protection with goggles or face-shield. Lastly, patients should be encouraged to wear surgical masks whenever possible.

Practical considerations for spirometry during the COVID-19 outbreak: Literature review and insights

Background

As the Coronavirus disease 2019 (COVID-19) is spreading worldwide, countries are dealing with different phases of the pandemic. Lately, scientific evidence has been growing about the measures for reopening respiratory outpatient services during the COVID-19 pandemic. We aim to summarize the key differences and similarities among recommendations by different national and international organizations.

Methods

We searched on Google and Pubmed for recently published National and International Recommendations/Guidelines/Position Papers from professional organizations and societies, offering a guidance to physicians on how to safely perform pulmonary function testing during COVID-19 pandemic. We also searched for spirometry manufacturers' operational indications.

Results

Indications on spirometry were released by the Chinese Task force, the American Thoracic Society, the European Respiratory Society, the Thoracic Society of Australia and New Zealand, the Société de Pneumologie de Langue Française, the Spanish Societies (Sociedad Espanola de Neumologia y Cirugia Toracica, Sociedad Espanola de Alergologia e Inmunologia Clinica, Asociacion de Especialistas en Enfermeria del trabajo, Asociacion de Enfermeria Comunitaria), the Sociedade Portuguesa de Pneumologia, the British Thoracic Society/Association for Respiratory Technology & Physiology, the Irish Thoracic Society, the Sociedad Uruguaya de Neumologia, the Italian Thoracic Society and the Italian Respiratory Society, Cleveland Clinic and Nebraska Medical Center. Detailed technical recommendations were found on manufacturers’ websites. We found several similarities across available guidelines for safely resuming pulmonary function services, as well as differences in criteria for selecting eligible patients for which spirometry is deemed essential and advice which was not homogenous on room ventilation precautions.

Conclusions

This study shows a synthesis of national/international guidelines allowing practicing physicians to adapt and shape the way to organize their outpatient services locally. There is generally good agreement on the importance of limiting pulmonary function testing to selected cases only. However, significant differences concerning the subsets of candidate patients, as well as on the management of adequate room ventilation, were observed.

Novel coronavirus SARS-CoV-2 and COVID-19. Practice recommendations for obstetric anaesthesia: what we have learned thus far

SARS-CoV-2 is a novel coronavirus causing a global pandemic of a severe respiratory illness known as COVID-19. To date, globally, over 30,000 people have died from this emerging disease. As clinicians and healthcare systems around the world are rapidly adapting to manage patients with COVID-19, limited data are emerging from different patient populations to support best-practice and improve outcomes. In this review, we present a summary of emerging data in the obstetric population and offer obstetric and anaesthetic clinicians around the world a set of evidence-driven, practice-based recommendations for the anaesthetic management of pregnant women with suspected or confirmed COVID-19.

Anesthesia for oral surgeries during the COVID-19 pandemic

The severe acute respiratory syndrome corona virus 2(SARS-Cov2) virus replicates in the nasal cavity, nasopharynx, and the oropharynx. During oral surgery, the risk of viral transmission is high during instrumentation in these areas, while performing airway management procedures, the oral surgery itself, and related procedures. During the corona virus disease 2019 (COVID-19) pandemic, patients with an oral pathology usually present for emergency procedures. However, patients with oral cancer, being a semi-emergency, may also present for diagnostic and therapeutic procedures. When elective surgeries are resumed, these patients will come to the operating room. In asymptomatic patients, the false-negative rate can be as high as 30%. These patients are a source of infection to the healthcare workers and other patients. This mandates universal precautions to be taken for all patients presenting for surgery. Lesions along the airway, distorted anatomy secondary to cancer therapy, shared airway with the surgeon, surgical handling of the airway and the risk of bleeding, make airway management challenging in these patients, especially while wearing personal protective equipment. Airway management procedures, oral surgery, use of cautery, and other powered surgical instruments in the aero digestive tract, along with constant suctioning are a source of significant aerosol generation, further adding to the risk of viral transmission. Maintaining patient safety, while protecting the healthcare workers from getting infected during oral surgery is paramount. Meticulous advance planning and team preparation are essential. In this review, we discuss the challenges and recommendations for safe anesthesia practice for oral surgery during the COVID-19 pandemic, with special emphasis on risk mitigation.

Face Masks and Respirators in the Fight against the COVID-19 Pandemic: A Review of Current Materials, Advances and Future Perspectives

The outbreak of COVID-19 has spread rapidly across the globe, greatly affecting how humans as a whole interact, work and go about their daily life. One of the key pieces of personal protective equipment (PPE) that is being utilised to return to the norm is the face mask or respirator. In this review we aim to examine face masks and respirators, looking at the current materials in use and possible future innovations that will enhance their protection against SARS-CoV-2. Previous studies concluded that cotton, natural silk and chiffon could provide above 50% efficiency. In addition, it was found that cotton quilt with a highly tangled fibrous nature provides efficient filtration in the small particle size range. Novel designs by employing various filter materials such as nanofibres, silver nanoparticles, and nano-webs on the filter surfaces to induce antimicrobial properties are also discussed in detail. Modification of N95/N99 masks to provide additional filtration of air and to deactivate the pathogens using various technologies such as low- temperature plasma is reviewed. Legislative guidelines for selecting and wearing facial protection are also discussed. The feasibility of reusing these masks will be examined as well as a discussion on the modelling of mask use and the impact wearing them can have. The use of Artificial Intelligence (AI) models and its applications to minimise or prevent the spread of the virus using face masks and respirators is also addressed. It is concluded that a significant amount of research is required for the development of highly efficient, reusable, anti-viral and thermally regulated face masks and respirators.

Practical recommendations in the obstetrical patient with a COVID-19 infection

La infección por COVID-19 afecta también a las pacientes obstétricas. La atención obstétrica habitual ha continuado a pesar de la pandemia. Existen series de casos de pacientes obstétricas. Parece que las técnicas neuroaxiales son seguras y es importante asegurarse que los bloqueos funcionen correctamente antes de una cesárea. Es por esto que se recomienda que los bloqueos sean realizados por anestesiólogos expertos. La protección y seguridad de los profesionales es un punto fundamental y, en caso de anestesia general, también se recomienda acudir al anestesiólogo más experto. Las pacientes gravemente enfermas deben reconocerse rápida y precozmente, para poder suministrarles el tratamiento adecuado lo antes posible. La susceptibilidad a las trombosis hace que la anticoagulación profiláctica sea prioritaria.

Modeling of the Transmission of Coronaviruses, Measles Virus, Influenza Virus, Mycobacterium tuberculosis, and Legionella pneumophila in Dental Clinics

Dental health care workers are in close contact to their patients and are therefore at higher risk for contracting airborne infectious diseases. The transmission rates of airborne pathogens from patient to dental health care workers are unknown. With the outbreaks of infectious diseases, such as seasonal influenza, occasional outbreaks of measles and tuberculosis, and the current pandemic of the coronavirus disease COVID-19, it is important to estimate the risks for dental health care workers. Therefore, the transmission probability of these airborne infectious diseases was estimated via mathematical modeling. The transmission probability was modeled for Mycobacterium tuberculosis, Legionella pneumophila, measles virus, influenza virus, and coronaviruses per a modified version of the Wells-Riley equation. This equation incorporated the indoor air quality by using carbon dioxide as a proxy and added the respiratory protection rate from medical face masks and N95 respirators. Scenario-specific analyses, uncertainty analyses, and sensitivity analyses were run to produce probability rates. A high transmission probability was characterized by high patient infectiousness, the absence of respiratory protection, and poor indoor air quality. The highest transmission probabilities were estimated for measles virus (100%), coronaviruses (99.4%), influenza virus (89.4%), and M. tuberculosis (84.0%). The low-risk scenario leads to transmission probabilities of 4.5% for measles virus and 0% for the other pathogens. From the sensitivity analysis, it shows that the transmission probability is strongly driven by indoor air quality, followed by patient infectiousness, and the least by respiratory protection from medical face mask use. Airborne infection transmission of pathogens such as measles virus and coronaviruses is likely to occur in the dental practice. The risk magnitude, however, is highly dependent on specific conditions in each dental clinic. Improved indoor air quality by ventilation, which reduces carbon dioxide, is the most important factor that will either strongly increase or decrease the probability of the transmission of a pathogen.