Noninvasive ventilation masks with viral filters to protect health care workers from SARS-CoV-2 / Coronavirus infections

Abstract

Background:There is a shortage of masks and respirators for the protection of health care professionals during the current SARS-CoV-2 / Coronavirus pandemic. Masks for non-invasive ventilation (NIV) in combination with viral-proof filters could serve as an alternative protection measure. We wanted to determine the aerosol filtering efficacies of such devices in comparison to conventional surgical masks, N95 and FFP3 respirators.Method:Masks and respirators were mounted on a ventilated mannequin head in a test-chamber.Absorption of radioactive particles was measured compared to a non-filtered reference port.Results: Filter efficacies were 93.3 ± 1.5 % for a ResMed AcuCare NIV-mask plus filter, 71.2 ± 0.2 % for a ResMed Mirage Quattro FX NIV-mask plus filter, 89.4 ± 0.9 % for a Loewenstein JOYCEclinc FF NIV-mask plus filter, 48.4 ± 4 % for a surgical mask with rubber band, 60.5 ± 9.1 % for a surgical mask with ribbons, 56.9 ± 7.5 % for a FFP3 respirator, 64.5 % ± 5.1 for a N95 respirator. The ResMed AcuCare and the Loewenstein JOYCEclinic FF mask were more effective than any other of the tested devices (p < 0.001 and p = 0.001 respectively) Conclusion:NIV masks with viral-proof filters effectively filter respirable particles. Two tested NIV masks were more effective than the tested FFP3 and N95 respirators.

Evaluation and discussion of handmade face-masks and commercial diving-equipment as personal protection in pandemic scenarios

“…The user has to make sure that there are no harmful chemicals such as glass fibres within the material of the bag before it is used for constructing a mask. However, in our experiment and in line with the results published by the military university Munich, the masks made of a cleaner bag had a efficacy below, but near to a commercial N95 mask in our previous experiments [6]. The oneway expiration valve is not necessary for the proper function of the mask and is only applied to make the longer use of the mask more comfortable.…”

“…Analog to the good efficiency of commercial continuous-positive-airway-pressure (CPAP)masks attached to antiviral filters [6], the full-face diving mask Easybreath 1 shows good filtration result. This mask has a separate inspiration and expiration pipe in order to reduce dead space.…”

“…The method was recently described by our workgroup on Research-Square [6], and Sodium-Chloride (NaCl) aerosol is used to test respiratory masks during their official classification process (EN149:2001). In brief, 99m-Tc-DTPA (diethylenetriamine 131 pentaacetate) with an activity of 150MBq/ml was nebulized using a Pari LC Sprint Star nebulizer (Paris, Starnberg, Germany), filled with 6ml of solution.…”

“…We recently evaluated different commercial masks and a scarf with respect to their filter efficacy [6]. As there is a growing number of templates for 3D printed masks on public depositories (e.g.…”

Care for Patients With Neuromuscular Disorders in the COVID-19 Pandemic Era

“…An antiviral filter should be used at the ventilator outlet of the inhalation circuit and after the mask ( 8 ). Several innovative NIV interface designs have been applied clinically, providing a more closed ventilation system ( 22 , 26 , 33 ). It should be addressed that patients undergoing NIV should remain under close monitoring and shift to a conventional ventilator if showing rapid deterioration or lack of improvement ( 6 ).…”