Covid-19 FAQ

The exterior of the ventilator can be disinfected according to the cleaning and disinfection protocol as described in the respective device’s operator’s manual.

The following disinfectants are effective against SARS-CoV-2 (synonym: new corona virus) and can be used on all Hamilton Medical ventilators’ housings and touch screens.

- Bacillol AF / Bacillol AF Tissues

- Bacillol 30/ Bacillol Tissues

- Microbac Tissues

- Microbac forte

- Mikrozid AF

- Mikrozid sensitive wipes

- Ecolab Sani Cloth

- Incidin Rapid

- Incidin Foam

- Incidin Pro

It is important to follow the instructions for use provided by the respective manufacturer of each product. The operator’s manual for each ventilator model may list additional products (e.g., Ethanol 70%) to be used specifically for disinfection of that particular ventilator.

• • Hamilton Medical does not recommend the use of one mechanical ventilator for more than one patient. To ensure appropriate and lung-protective ventilation, monitoring and ventilator settings need to apply for one patient only. This is made possible by the proximal flow- and pressure-measurement technology in our devices.
    If you use our ventilators on more than a 1:1 patient to ventilator ratio, be aware that:
    
    a) This will most probably result in distending (and damaging) the healthier lungs of the ventilated patients, while the lower compliant lungs will collapse further.
    b) The increase in artificial airways (breathing tubes) will reduce the ventilator's performance (pressures will be lost due to circuit/breathing tube compliance)
    c) There is no other recommendation than to put the proximal flow sensor at the Y-piece of the ventilated patient (which patient will you choose?).
    d) Recommendations for COVID-19 and ARDS include tidal-volume monitoring and limitations, and individual PEEP settings: How can you make sure this works for two patients on one ventilator?
    e) Weaning the patient from the ventilator is one of the most important way to ensure the availability of ventilators. How can you be sure you can wean your patient with the likelihood of total asynchrony between patient and ventilator?
    f) Running two patients on one ventilator will also involve serious hygiene problems. Patients may also have additional pathogens like multi-resistant bacteria or other viruses, etc.
    g) Important procedures like prone positioning will not be possible in such a setting.
    h) Click here to read the joint statement from the Anesthesia Patient Safety Foundation (ASPF), Society of Critical Care Medicine (SCCM), American Association for Respiratory Care (AARC), American Society of Anesthesiologists (ASA), American Association of Critical‐Care Nurses (AACN), and American College of Chest Physicians (CHEST), who have joined together to address the issue of placing multiple patients who have respiratory failure on a single ventilator.
    Should you run out of ventilator equipment, we recommend instead:
    
    a) Informing the local authorities and asking for help
    b) Informing the clinical directorate: all non-essential treatments (surgery, endoscopy, examinations…) should be postponed to free up all ventilators within the hospital
    c) Informing the operating-room department: ask for anesthesia devices, transport ventilators, old ventilators in the basements and whatever works within its intended use
    d) Asking hospitals in the region for help (ventilators): the local authorities may help
    e) Asking private operation centers for their anesthesia devices: once again, the local authorities may have to help
    f) Trying to use NIV devices (not on COVID-19 patients) wherever possible instead of invasive ventilators, and getting patients weaned and extubated as soon as possible
    g) Trying to reduce the number of COPD patients who have their own sleep apnoea devices, but are connected to an ICU ventilator in hospital. Try to bring these patients back to a state where they can be ventilated on their own equipment

If the ventilator is equipped according to the instructions as described in the respective operator’s manual, there is no specific action to be performed on the ventilator. Carry out the regular cleaning and disinfection of the device as described in the hospital’s hygiene protocol. In this case, ensure that the disinfectant is at the very least effective against enveloped viruses.

As SARS-CoV-2 is highly infectious, the patient should be treated in quarantine conditions and hospital staff should take extreme care with personal hygiene. Use of single-use consumables is highly recommended to avoid any cross-contamination within the hospital.

Particulate matter (PM) in the air, whether in solid or liquid form, can affect our health. Particularly those particles below 2.5 micrometers (also known as microns; μm) represent a hazard, as they are able to enter our bloodstream. Nanoparticles can be as small as 0.1 right down to 0.001 μm.

Sizes of some well-known bacteria and viruses are as follows:

Influenza A virus: 0.08 - 0.12 μm

HIV: 0.08 μm

Hepatitis C virus: 0.05 μm

Mycobacterium tuberculosis 1.0 μm

The very common staphylococci (e. g. staphylococcus aureus) are spherical cells of about 1 μm that grow in clusters.

The coronavirus species COVID-2019, MERS-CoV and SARS-CoV range in size from 0.06 to 0.2 μm.

It is widely believed that HEPA filters are only capable of capturing particles sized 0.3 μm or larger. However, this belief is based in part on an incorrect understanding of how HEPA filters work. The fact is that particles of around 0.3 μm are the hardest to catch (1); for this reason, that size is used to measure the effectiveness of HEPA filters. Much smaller nanoparticles are in fact easier to catch. But why is this so?

For larger particles, the HEPA filter acts like a net as we would expect. Particles greater than 0.3 μm in size simply cannot get through: either they do not fit through the holes or they hit the filter fibers due to inertia. For smaller particles, on the other hand, it would seem logical that they can simply go through the holes. However, this is not the case. The tiny mass of particles less than 0.3 μm means they do not fly straight; instead, they are bounced off other molecules as they collide with them and thus move in completely random patterns. As a result, they hit the filter fibers and then remain stuck in them. This is the principle of Brownian movement.

Tests carried out by the NASA (1) showed that HEPA filters are highly effective in capturing an extremely high percentage of up to 100% of nanoparticulate contaminants, as well as the larger particles greater than 0.3 μm. For particles of around 0.3 μm there is just a small drop in efficiency; this size is thus called the most penetrating particle size (MPPS) in standards for HEPA filters (see image).

According to European standards, there are 17 classes of filters – the higher the class, the greater the efficiency. Classes E10 to E12 are Efficient Particulate Air (EPA) filters, H13 and H14 are HEPA filters, and U15 to U17 are Ultra Low Penetration Air (ULPA) filters. These classes are covered by the European standard EN 1822, which assesses the filtration performance of the filter for the MPPS. According to this standard, a HEPA filter must remove at least 99.95% of particles sized 0.3 μm or larger (2). US government standards require a filter to remove 99.97% of particles sized 0.3 μm in order to qualify as HEPA (3). In other words, for every 10,000 particles sized 0.3 microns in diameter, only three of them may pass through.