Use of Portable Air Purification Systems to Eliminate Aerosol Particles from Patient Rooms

SARS-CoV-2 is mainly transmitted via airborne aerosols. We determined the efficacy of two different indoor air-purification systems and compared them to conventional measures of room ventilation. Radioactive particles with a mass median aerodynamic diameter of 0.6 +/- 0.4 [inn were nebulized from the head position of a simulated patient inside a 38 m(3) measuring room. Air samples were drawn using an artificial lung from outside the room from the head and belly position of the simulated patient. The radioactivity from these air samples was determined in % of the minute-by-minute release of aerosol by the simulated patient. The samples were taken with the windows closed, with the windows open and with two different air purification systems in different locations. Opening the windows while the fan was working did not reduce the cumulative mass of sampled particles during ongoing nebulization. Only the more powerful air purifier was able to decrease cumulative sampled radioactivity almost to zero when positioned close to the emitting particle source. We observed air-turbulences caused by the air intake of the air purifier resulting in regional particle concentration peaks. Measurements and calculations demonstrate that indoor air purification systems can be effective measures to eliminate airborne particles. The air cleaning capacity of the system must be matched to the room size and the air intake of the units should be positioned close to the particle source.

[Investigation of the Filter Performance in a Sample of Standardised Particle-filtering Half Masks]. / Stichprobenuntersuchung der Filterleistung von normierten partikelfilternden Halbmasken.

BACKGROUND: Thanks to a simplified special approval process that was valid until October 1st, 2020, a large number of particle-filtering half masks have come onto the German market. When caring for SARS-CoV-2 infected patients, the RKI recommends wearing particle-filtering half masks with a filter performance of at least 94 %, which corresponds to FFP class 2 according to EN 149:2001+A1:2009. We have examined 15 particle-filtering half masks with different specifications for their filter performance METHOD: The masks were clamped in a jig in an airtight test box. Radioactive particles with a size of 0.6 ±â€Š0.4 µm were nebulized into the box and sucked into a filter through the port of the jig and an unfiltered reference port using an artificial lung. The activity deposited on the filter was measured by means of a gamma camera. The filter performance was calculated from this. RESULTS: Five of the 15 masks tested had a filter performance of less than 94 % and therefore do not meet the FFP2 standard. The filter performance of these masks was 71.8 ±â€Š2.3 %, 73.2 ±â€Š2.3 %, 78.2 ±â€Š6.7 %, 92.2 ±â€Š0.5 % and 85.9 ±â€Š1.6 %. CONCLUSION: One third of the examined masks did not meet the recommended FFP2 standard, which is recommended for the care of SARS-CoV-2 infected patients. A comprehensive review of already approved products by the supervisory authorities is advisable.

[Management of diagnostic procedures and treatment of sleep related breathing disorders in the context of the coronavirus pandemic]. / Diagnostik und Therapie schlafbezogener Atmungsstörungen im Zusammenhang mit der Corona­Pandemie: Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V. (DGP), Deutsche Gesellschaft für Schlafforschung und Schlafmedizin (DGSM).

When providing sleep medical services special aspects must be taken into account in the context of the coronavirus pandemic. Despite all prevention, due to the high number of unrecognized cases, SARS-CoV2 contacts in the sleep laboratory must be expected and appropriate precautions are necessary. Nevertheless, the continuation or resumption of sleep medical services under the appropriate hygiene measures is strongly recommended to avoid medical and psychosocial complications. There is no evidence for a deterioration of COVID-19 through CPAP therapy. In principle, the application of positive pressure therapy via various mask systems can be accompanied by the formation of infectious aerosols. In the case of confirmed infection with SARS-CoV2, a pre-existing PAP therapy should be continued in an outpatient setting in accordance with the local guidelines for home isolation, since discontinuation of PAP therapy is associated with additional cardiopulmonary complications due to the untreated sleep-related breathing disorder. According to the current state of knowledge inhalation therapy, nasal high-flow (NHF), and PAP therapy can be carried out without increased risk of infection for health care workers (HCW) as long as appropriate personal protective equipment (eye protection, FFP2 or FFP-3 mask, gown) is being used.This position paper of the German Society for Pneumology and Respiratory Medicine (DGP) and the German Society for Sleep Medicine (DGSM) offers detailed recommendations for the implementation of sleep medicine diagnostics and therapy in the context of the coronavirus pandemic.

[Position Paper for the State of the Art Application of Respiratory Support in Patients with COVID-19 - German Respiratory Society]. / Positionspapier zur praktischen Umsetzung der apparativen Differenzialtherapie der akuten respiratorischen Insuffizienz bei COVID-19.

Against the background of the pandemic caused by infection with the SARS-CoV-2, the German Society for Pneumology and Respiratory Medicine (DGP e.V.), in cooperation with other associations, has designated a team of experts in order to answer the currently pressing questions about therapy strategies in dealing with COVID-19 patients suffering from acute respiratory insufficiency (ARI).The position paper is based on the current knowledge that is evolving daily. Many of the published and cited studies require further review, also because many of them did not undergo standard review processes.Therefore, this position paper is also subject to a continuous review process and will be further developed in cooperation with the other professional societies.This position paper is structured into the following five topics:1. Pathophysiology of acute respiratory insufficiency in patients without immunity infected with SARS-CoV-22. Temporal course and prognosis of acute respiratory insufficiency during the course of the disease3. Oxygen insufflation, high-flow oxygen, non-invasive ventilation and invasive ventilation with special consideration of infectious aerosol formation4. Non-invasive ventilation in ARI5. Supply continuum for the treatment of ARIKey points have been highlighted as core statements and significant observations. Regarding the pathophysiological aspects of acute respiratory insufficiency (ARI), the pulmonary infection with SARS-CoV-2 COVID-19 runs through three phases: early infection, pulmonary manifestation and severe hyperinflammatory phase.There are differences between advanced COVID-19-induced lung damage and those changes seen in Acute Respiratory Distress Syndromes (ARDS) as defined by the Berlin criteria. In a pathophysiologically plausible - but currently not yet histopathologically substantiated - model, two types (L-type and H-type) are distinguished, which correspond to an early and late phase. This distinction can be taken into consideration in the differential instrumentation in the therapy of ARI.The assessment of the extent of ARI should be carried out by an arterial or capillary blood gas analysis under room air conditions and must include the calculation of the oxygen supply (measured from the variables of oxygen saturation, the Hb value, the corrected values of the Hüfner number and the cardiac output). In principle, aerosols can cause transmission of infectious viral particles. Open systems or leakage systems (so-called vented masks) can prevent the release of respirable particles. Procedures in which the invasive ventilation system must be opened, and endotracheal intubation must be carried out are associated with an increased risk of infection.The protection of personnel with personal protective equipment should have very high priority because fear of contagion must not be a primary reason for intubation. If the specifications for protective equipment (eye protection, FFP2 or FFP-3 mask, gown) are adhered to, inhalation therapy, nasal high-flow (NHF) therapy, CPAP therapy or NIV can be carried out according to the current state of knowledge without increased risk of infection to the staff. A significant proportion of patients with respiratory failure presents with relevant hypoxemia, often also caused by a high inspiratory oxygen fraction (FiO2) including NHF, and this hypoxemia cannot be not completely corrected. In this situation, CPAP/NIV therapy can be administered under use of a mouth and nose mask or a respiratory helmet as therapy escalation, as long as the criteria for endotracheal intubation are not fulfilled.In acute hypoxemic respiratory insufficiency, NIV should be performed in an intensive care unit or in a comparable unit by personnel with appropriate expertise. Under CPAP/NIV, a patient can deteriorate rapidly. For this reason, continuous monitoring with readiness to carry out intubation must be ensured at all times. If CPAP/NIV leads to further progression of ARI, intubation and subsequent invasive ventilation should be carried out without delay if no DNI order is in place.In the case of patients in whom invasive ventilation, after exhausting all guideline-based measures, is not sufficient, extracorporeal membrane oxygenation procedure (ECMO) should be considered to ensure sufficient oxygen supply and to remove CO2.