Powered Air Purifying Respirator (PAPR) restores the N95 face mask induced cerebral hemodynamic alterations among Healthcare Workers during COVID-19 Outbreak

Evaluation of the effect of n95 face mask used by healthcare professionals on choroidal thickness

PURPOSE

We aimed to show the changes in choroidal thickness (CT) with spectral domain optical coherence tomography (SD-OCT) after prolonged use of N95 mask.

METHOD

The healthcare workers who use the N95 face-mask, between 30-50 years of age who have best corrected visual acuity (BCVA) ≥10/10, spherical or cylindrical refraction errors less than 2 diopters, with normal intra ocular pressure (IOP), axial length (AL) between 22-24 mm included in the study. The choroid was imaged with enhanced depth imaging (EDI) techniques using SD-OCT. CT was measured, subfoveal, at 1000 μm nasal and temporal of the center of the fovea. Measurements were first made after wearing the N95 mask for at least 2 h without removing it and repeated 15 min after removing.

RESULTS

After 2 h of the N95 mask using without removal, the mean subfoveal CT was 293.56 ± 76.12(min:185, max:479), the mean temporal CT was 253.81 ± 63.48(min:172, max:384), the mean nasal CT was 239.18 ± 53.92(min:139, max:356). Fifteen minutes after removal of the N95 mask, the mean subfoveal CT was 250.56 ± 52.48(min:172, max:397), the mean temporal was 218.40 ± 53.58(min:129, max:354), the mean nasal CT was 210.67 ± 53.31(min:132, max:366). The differences in subfoveal, temporal and nasal CT between 2 h of N95 mask use and 15 min after removal of the mask were statistically significant (p < 0.05 for each).

CONCLUSION

Hypercapnia due to prolonged use of the N95 mask may cause choroidal hemodynamic changes and transient increased choroidal thickness.

Use of powered air-purifying respirator(PAPR) as part of protective equipment against SARS-CoV-2-a narrative review and critical appraisal of evidence

BACKGROUND

The last 2 decades have seen an increasing frequency of zoonotic origin viral diseases leaping from animal to human hosts including Severe Acute Respiratory Syndrome Coronaviruses (SARS-CoV-2). Respiratory component of the infectious disease program against SARS-CoV-2 incorporates use of protective airborne respiratory equipment.

METHODS

In this narrative review, we explore the features of Powered Air Purifying Respirators (PAPR) as well as logistical and evidence-based advantages and disadvantages.

RESULTS

Simulation study findings support increased heat tolerance and wearer comfort with a PAPR, versus decreased communication ability, mobility, and dexterity. Although PAPRs have been recommended for high-risk procedures on suspected or confirmed COVID-19 patients, this recommendation remains controversial due to lack of evidence. Guidelines for appropriate use of PAPR during the current pandemic are sparse. International regulatory bodies do not mandate the use of PAPR for high-risk aerosol generating procedures in patients with SARS-CoV-2. Current reports of the choice of protective respiratory technology during the SARS-CoV-2 pandemic are disparate. Patterns of use appear to be related to geographical locations.

DISCUSSION

Field observational studies do not indicate a difference in healthcare worker infection utilizing PAPR devices versus other compliant respiratory equipment in healthcare workers performing AGPs in patients with SARS-CoV-2. Whether a higher PAPR filtration factor translates to decreased infection rates of HCWs remains to be elucidated. Utilization of PAPR with high filtration efficiency may represent an example of "precautionary principle" wherein action taken to reduce risk is guided by logistical advantages of PAPR system.

Effect of wearing a face mask on fMRI BOLD contrast

International spread of the coronavirus SARS-CoV-2 has prompted many MRI scanning facilities to require scan subjects to wear a facial covering ("mask") during scanning as a precaution against transmission of the virus. Because wearing a mask mixes expired air with the subject's inspired air stream, the concentration of inspired carbon dioxide [CO₂] is elevated, resulting in mild hypercapnia. Changes in the inspired gas mixture have been demonstrated to alter R2*-weighted Blood Oxygen Dependent (BOLD) contrast. In this study, we investigate a potential for face masking to alter BOLD contrast during a sensory-motor task designed to activate visual, auditory, and sensorimotor cortices in 8 subjects. We utilize a nasal cannula to supply air to the subject wearing a surgical mask in on-off blocks of 90s to displace expired CO₂, while the subject performs the sensory-motor task. While only a small fraction (2.5%) of the sensory-motor task activation is related to nasal air modulation, a 30.0% change in gray matter BOLD signal baseline is found due to air modulation. Repeating the scan with mask removed produces a small subject-specific bias in BOLD baseline signal from nasal air supply, which may be due to cognitive influence of airflow or cannula-induced hypoxia. Measurements with capnography demonstrate wearing a mask induces an average increase in ETCO₂ of 7.4%. Altogether, these results demonstrate that wearing a face mask during gradient-echo fMRI can alter BOLD baseline signal but minimally affects task activation.

Assessment of hypoxia and physiological stress evinced by usage of n95 masks among frontline dental healthcare workers in a humid western coastal region of India-A repeated measure observational study

Aim:

To assess the oxygen saturation in DHCWs using N95 and 3 ply surgical masks and determine the presence of any other subjective discomfort in them.

Settings and Design:

A repeated measure observational study conducted at the Tertiary Care Dental Institute situated in Goa, a western coastal region of India recording humid conditions year around.

Methods and Material:

Participants constituted 60 frontline DHCWs wearing N95 masks and 60 DHCWs working in non-clinical setting wearing surgical masks. After completion of a self-administered questionnaire their oxygen saturation and pulse rate were monitored at baseline, 60mins and 120mins using pulse oximetry. Statistical Analysis: Mann Whitney u test compared oxygen saturation between the two groups. Friedmann and Wilcoxon signed rank test with Bonferroni correction computed differences within group at various time intervals. Binary logistic and linear regression was used to compare the study variables with outcome measure. p value was set at < 0.05.

Results and Conclusion:

Oxygen saturation reported a significant drop post one hour of wearing N95 masks which increased in the second hour. Prolonged use of N95 mask in humid environment adds to the body's physiological burden or perceptions of discomfort and exertion. Efforts need to be taken to address this for better compliance to the use of these protective gears.

Adverse Effects of Personal Protective Equipment Among Intensive Care Unit Healthcare Professionals During the COVID-19 Pandemic: A Scoping Review

INTRODUCTION

To avoid exposure to SARS-COV-2, healthcare professionals use personal protective equipment (PPE) while treating COVID-19 patients. Prior studies have revealed the adverse effects (AEs) of PPE on healthcare workers (HCWs); however, no review has focused on the AEs of PPE on HCWs in intensive care units (ICUs). This review aimed to identify the AEs of PPE on HCWs working in ICUs during the COVID-19 pandemic.

METHODS

A scoping review was conducted. MEDLINE, CINAHL, the World Health Organization (WHO) global literature on COVID-19, and Igaku-chuo-zasshi (a Japanese medical database), Google Scholar, medRxiv, and Health Research Board (HRB) open research were searched from January 25-28, 2021. The extracted data included author(s) name, year of publication, country, language, article title, journal name, publication type, study methodology, population, outcome, and key findings.

RESULTS

The initial search identified 691 articles and abstracts. Twenty-five articles were included in the analysis. The analysis comprised four key topics: studies focusing on PPE-related headache, voice disorders, skin manifestations, and miscellaneous AEs of PPE. The majority of AEs for HCWs in ICUs were induced by prolonged use of masks.

CONCLUSION

The AEs of PPE among HCWs in ICUs included heat, headaches, skin injuries, chest discomfort, and dyspnea. Studies with a focus on specific diseases were on skin injuries. Moreover, many AEs were induced by prolonged use of masks.

Personal Protective Equipment and Headaches: Cross-Sectional Study Among Moroccan Healthcare Workers During COVID-19 Pandemic

Background

Healthcare workers in frontline during the coronavirus 19 disease (COVID-19) pandemic are mandated to wear specific personal protective equipment (PPE) including high filtrating masks and/or eye protection during extended period of time. Compressive headaches secondary to PPE use including N95 masks have been reported. We aim to describe subtypes of headache related to PPE use in our hospital in Casablanca and working condition factors associated with it.

Methods

We conducted a cross-sectional study among healthcare workers in frontline at Cheikh khalifa International University Hospital, using an online questionnaire. We collected demographic data, comorbidities and previous headaches history. Data about working conditions during pandemic, type and duration of PPE use were described. We calculated the prevalence of De Novo or an aggravated headache among healthcare workers. We studied correlations between PPE related headaches and working conditions and trends in PPE use during the pandemic. Finally, we described the overall discomfort related to PPE use.

Results

A total of 155 healthcare workers responded to the questionnaire. The N95 masks were the most used type (95.5%) associated with an eye protection in 61.3%. The overall prevalence of headache related to PPE was 62%. It was experienced De Novo in 32.9%, while it was an aggravation of pre-existing headache in 29%. Working more than 8 hours per shift during the pandemic was correlated to De novo headache (p = 0.008). The profession of doctor and working more than 12 hours per shift were correlated to aggravated headache (p = 0.02, p = 0.023). Healthcare workers experienced moderate discomfort, blurred vision and reduced concentration. They judged their professional performance mildly reduced by the use of PPE.

Conclusion

The increased use of PPE, especially high filtrating masks during the COVID-19 outbreak is responsible for generating headaches in healthcare workers on frontline either De novo or as an aggravation of pre-existing one. Working conditions have the greater impact on generating these types of headaches more than any pre-existing comorbidity. These findings should be considered to accommodate health care professionals to increase efficacy and adherence to protective measures during pandemic. 

COVID-19: What do we know?

•Evidence regarding the provision of orthodontic care during the COVID-19 pandemic is examined.