The Effect of N95 Respirators on Vital Parameters, PETCO2 and Physical Comfort among Healthcare Providers at the Pandemic Clinics (preprint)

Background: Wearing face shields and masks, which used to have very limited public use before the Covid-19 outbreak, has been highly recommended by organizations, such as CDC and WHO, during this pandemic period. The aim of this prospective study is to scrutinize the dynamic changes in vital parameters, change in end tidal CO2 levels, the relationship of these changes with taking a break, and the subjective complaints caused by respiratory protection while healthcare providers are performing their duties with the N95 mask. Methods The prospective cohort included 54 healthcare workers (doctors, nurses, paramedics) who worked in the respiratory unit of the emergency department (ED), performed their duties by wearing valved N95 masks, face shields. The vital parameters and end-tidal CO2 levels were measured at 0-4th-5th-and 9th hours of the work-shift. Results Only the decrease in diastolic BP between 0-9 hours was statistically significant (p=0.038). Besides, MAP values indicated a significant decrease between 0-9 hours and 5-9 hours (p= 0.024 and p=0.049, respectively). In terms of the vital parameters of the subjects working with and without breaks, only PETCO2 levels of those working uninterruptedly increased significantly at the 4th hour in comparison to the beginning-of-shift baseline levels (p=0.003). Conclusion Although the decrease in SBP and MAP values is assumed to be caused by increased fatigue due to workload and work pace as well as increase in muscle activity, the increase in PETCO2 levels in the ED healthcare staff working with no breaks between 0-4 hours should be noted in terms of PPE-induced hypoventilation.

SARS-CoV-2 delta AY.1 variant cluster in an accommodation facility for COVID-19: Research study (preprint)

Background: This is a case report on a cluster infection of novel severe acute respiratory syndrome coronavirus 2 delta AY.1 variant at an accommodation facility and the subsequent attempts to isolate individuals who tested positive. Methods The background that facilitated this cluster was investigated, and the conditions in which infection was established, the infection route, and the effectiveness of routine measures were evaluated. Ninety-nine staff members had been working at the accommodation facility at the time of infection, and it was estimated that 10 members were infected with the delta AY.1 variant. Results Our results suggest that infection of staff from a patient staying overnight should be excluded. The factors contributing to the cluster infection involved short-distance conversations with individuals wearing non-woven three-layer masks moved out of position (non-woven) and gathering together with individuals wearing non-woven masks in hypoventilated conditions. Our findings also indicate that this variant is possibly airborne and can infect individuals in enclosed spaces with poor ventilation, even when either infected or exposed individuals wear non-woven masks. Conclusions The routine maintenance of systems established for the detection of infections and prompt and appropriate preventive measures following the identification of positive individuals will help prevent further cluster infections.

SARS-CoV-2 Delta AY.1 variant Cluster in an accommodation facility for COVID-19 (preprint)

This is a case report on a cluster infection of novel severe acute respiratory syndrome coronavirus 2 delta AY.1 variant at an accommodation facility and the subsequent attempts to isolate individuals who tested positive. The background that facilitated this cluster was investigated, and the conditions in which infection was established, the infection route, and the effectiveness of routine measures were evaluated. Ninety-nine staff members had been working at the accommodation facility at the time of infection, and it was estimated that 10 members were infected with the delta AY.1 variant. Our results suggest that infection of staff from a patient staying overnight should be excluded. The factors contributing to the cluster infection involved short-distance conversations with individuals wearing non-woven three-layer masks moved out of position (non-woven) and gathering together with individuals wearing non-woven masks in hypoventilated conditions. Our findings also indicate that this variant is possibly airborne and can infect individuals in enclosed spaces with poor ventilation, even when either infected or exposed individuals wear non-woven masks. The routine maintenance of systems established for the detection of infections and prompt and appropriate preventive measures following the identification of positive individuals will help prevent further cluster infections.

Adverse effects of COVID-protective face-masks and wearing durations onto respiratory-haemodynamic physiology and exhaled breath constituents (preprint)

While protecting against the coronavirus transmission, face-masks may have adverse effects on respiratory-haemodynamic parameters. We investigated immediate and progressive effects of FFP2 and surgical masks on exhaled breath constituents and physiological attributes in 30 healthy volunteers at rest. We continuously monitored exhaled breath profiles in the mask space in elderly (age: 60–80 years) and adults (age: 20–60 years) over a period of 30 min by high-resolution real-time mass-spectrometry (PTR-ToF-MS). Peripheral oxygen saturation, respiratory- and haemodynamic parameters were measured (non-invasively) continuously in parallel. Profound and consistent decrease in SpO 2 and increase in pET-CO 2 indicates ascending deoxygenation and inadequate ventilation in subjects. Cardiac output and MAP changed as secondary. Exhalation of blood-borne volatile metabolites mirrored behaviour of cardiac output, MAP, SpO 2 , respiratory rate and pET-CO 2 . FFP2 masks affected more pronouncedly than surgical masks. Elderly cohort was more vulnerable to those effects. Exhaled humidity increased and exhaled oxygen decreased significantly over time. Breath profiles of endogenous aldehydes, hemiterpene, organosulfur, short-chain fatty acids, alcohols and ketone indicated cross-talks between physio-metabolic effects such as hypoxia, oxidative stress, hypoventilation, compartmental vasoconstriction, altered systemic bacterial activity and energy homeostasis. Concentrations of exogenous VOCs such as aromatics, nitrile and monoterpene depicted compartmental storage and washout. Breathomics allows unique physio-metabolic insights into side effects of face-mask wearing. Mask induced deoxygenation, oxidative stress, CO 2 rebreathing, vasoconstriction and blood pressure fluctuations in elderly were clinically concerning (as leading towards hypoxia and hypoventilation). Intelligible global-pandemic policies should reconsider the type and wearing durations of recommended face-masks, based upon age and/or cardio-pulmonary conditions.