Original title is "Emergency mask for hospital ventilators". The title on the post is misleading.
A ventilator is a machine with electronics, moving parts, and sensors that pushes air into people's lungs and pulls it back out. This is an improvised replacement for one of the less- or non-reusable accessories in short supply, the mask that goes on the patient.
Technically it is a "ventilation-assisted mask" but according to the sketches, it does plug directly into the hospital's oxygen system. Scroll down to the bottom to see sketches.
What you refer to as the "hospital's oxygen system" is the oxygen output port on a ventilator. See also this note in the text:
"The prototype as a whole has been tested on one of our colleagues directly inside the Chiari Hospital, connected to the ventilator body, and has proven to be correctly working."
I’m having trouble seeing why this couldn’t be a widespread solution. It uses the same supply lines; the mask is designed to maintain a seal and support normal breathing.
What prevents this from being an option when the alternative is, I dunno, death?
Is this actually a “ventilator”? Or is it just a mask and it’s the rest of the air delivery system that’s in short supply? Can anyone point to a good basic intro to the “design a ventilator” problem?
A ventilator is a pretty complex, configurable piece of electronics and machinery. It needs to push air in and pull it out at specific volumes and pressures (usually hand-calibrated to the individual patient by a doctor), and do so with a pressure curve that does as little damage to the lungs in the process.
The machines are indeed in short supply (which this doesn't fix), but so are a lot of parts that become contaminated after use on a patient (which this does fix). See also that project going around for 3D-printing replacement valves.
It is a ventilator in terms of displacing exhaled CO2 via the volume of air moving through the circuit, mask and lungs. It also provides positive pressure to aid in more effective oxygenation.
There is alot of selective focus and attention to "ventilators" currently. The danger is people believe that a fuller featured ventilator will save them when in reality (it will in some cases) public health focus should (arguably is) be on everything that can be done to keep COVID patients from being intubated and needing a full featured ventilators.
There is a risk that we run out of ventilators because they are dedicated to long term life support of patients that become dependent on them when they could be providing the short term ventilatory support of patients who will recover enough not need one. This is another scenario given our medical capabilities, well trained healthcare workers, and cultural outlook we are not yet talking about.
I saw the Italians intubation protocol has this in mind. A very public discussion of these issues could create more panic than productive conversations in the media, but it really it will need to be addressed openly sooner or later before long-term ventilators start stacking.
One person I speak to online is a reverend, who's been asked to be part of an ethics committee which will be making those decisions when resources run out
What do you optimise for?
Number of lives saved? Number of Years saved (so better to save someone with a life expectancy of 40 years than 2 people of LE of 5 years each)? Do you remove ventilators from those who it's just delaying the inevitable? How to do you factor in non-covid cases?
Do you take into account how "good" the patient was? Were they self isolating or did they go to a pub lockin? Have they been hoarding toilet paper? Do you save the person who caught it performing CPR? What about the Key Worker who caught it while delivering food to the town? How about the dumbass politician who's encouraging people to ignore the restrictions?
Generally (Used to be) in the united states the social worker will present the general ethical frameworks to reason within and it is up to family to provide the answer. Ethics boards develop recommendations as needed, when courts have to step in.
I will say working in a Trauma and ICU rooms, families are generally well aware of the decisions to be made when it is time.
They are assigned a triage score and that score will be updated routinely. As beds open, the people who fit the criteria get the bed. I believe that is fairly standard in a public hospital type setting.
I have only ever worked in public and military icu, wards, er and trauma rooms so I do not know too many details on how that works in practice.
Copying over my response to another comment, because I think people will see this and get the wrong idea:
What you refer to as the "hospital's oxygen system" is the oxygen output port on a ventilator. See also this note in the text:
"The prototype as a whole has been tested on one of our colleagues directly inside the Chiari Hospital, connected to the ventilator body, and has proven to be correctly working."
(Note that the mask is general-purpose, so they mention in the video that it can also be attached to a CPAP machine or to a plain old oxygen feed for less severe cases; but people who need a ventilator are still going to need a ventilator with this. They're just going to have a mask available.)
Relatedly, some engineering students from Tunisia created 3D printed protective masks and started supplying hospitals as they have a shortage of those. The prototype is open source : https://github.com/FAB619/Protection-Mask--COVID-19
I'm not a ventilator specialist, but this is gaining some traction and I fail to understand how it really helps. Is the ventilator shortage just a mask shortage ? Isn't there a quite complicated machine plugged to the mask ? With complex valves and a motor and pressure sensors and alarms and whatever ?
There has been some discussion on 3D printing medical ventilators on the local hackerspace mailing list.
One of the participants used to work at a company which builds those and made similar points:
There are different systems, one are the C/VPAP which are only for ventilation during sleep, avoiding a closure of the pharynx by increasing the pressure to a certain maximum value. Some of those have parameters also taking care of the patient's breathing pressure etc. but in general can only help for "better sleep" – if they fail, then you have a bad sleep but won't die.
The systems they use in hospitals are the complex machines you describe: they have battery power, measure the flow of breath, have alarms etc. Even here they distinguish between "supported breathing" and "keeping alive", i.e. in the former case the machine helps you to breathe while the second takes care of breathing for you.
In Italy, a doctor asked for a replacement part of their ventilators which was then 3D printed – the valves mentioned in the article. This seems to have led to a surge in people now trying to build, design, etc. ventilators which can essentially be build anywhere, to combat supply chain shortages.
Again: You are right, medical ventilators are a tricky business and difficult to build. But in this case, the ventilators seem to be there, they just need the valves, which can be printed. And they put up a huge disclaimer that patients need to agree to use unapproved devices.
Apparently doubling the pressure allows two or maybe more patients to be hooked to the same ventilator with a kind of T-junction. In this situation you would only need an extra mask.
Non Invasive Ventilation is the preferred mode to assistant patients with the lung pathology COVID creates. This requires higher than normal lung pressures for oxygenation as the concentration of O2 can be detrimental to the lungs causing a worsening. The extra pressure means a lower concentration of O2 is needed to help the patient.
Intubation adds more risk to the patients lungs recovering because the volumes of air moved in an out can also cause injury; as the lungs are no longer moving as well with the increased fluid COVID patients experience. A full featured ventilator is not a silver bullet, it is a sign that things are very serious for the patients lungs. The shorter amount of time on the ventilator the better, which also means no ventilator unless absolutely necessary.
Using a mask like this does the basics, but we do have to rely on the patient to move their own air volumes in and out. Often they are able to do this, so this mask could provide real benefits.
The bubble helmets you can see in Italian hospital footage have been shown in an 2016 study to reduce the need to intubate and put patients on a full featured ventilator. The caveat being the COVID pandemic experience will glean a lot more insight into keeping patients from being intubated and off of full featured ventilators.
Masks and valves and tubing are much less durable goods than the ventilator itself; some of them wear out, some of them become biohazards after use, etc. So there's both a shortage of the parts required to keep existing ventilators in continued use, and of the machines themselves.
The panic of where we will get the ventilators from does not have to be the sole focus. Not every patient will need a million dollar ventilator.
If someone is self isolated with the disease then they may need a lower technology solution such as a dehumidifier. In that way they can avoid the secondary bacterial infections that are the real killer. They can recover in a room that won't be growing mould because it is damp from their breathing.
A humble dehumidifier could put someone on the road to recovery before it gets to the ventilator stage in a northern climate where damp is a problem.
It's amazing what people are coming up in the last weeks to make things work, even though they don't follow the standards, the regulations, etc. etc. The human brain under a certain amount of stress/motivation can come up with a sh load of ideas and solutions.
I think a lot of it is finally feeling safe to experiment. I'm sure ideas like this were always around but people knew they'd be in prison if they tried it.
The west gone wild
Pioneering spirit
A golden age for cowboys
Warstories for grandchildren
These hacks have been around for years - they're standard practice in mass casualty incidents (e.g. a lot of the research on ventilator-sharing was done after the Vegas shooting) where sudden surges of requirements outpace local supply. We're just in a situation where well-known and -studied emergency procedures are becoming standard practice.
Really hope that our societies can fund some research and development to bring elasticity to health care capacity. This won't be the last time we as humans will need it, and it will help if some smart people work on this instead of ad click optimization..
A doctor who might reasonably know what's what, identifies a problem and a novel solution is found.
> we have been contacted by a former head physician of the Gardone Valtrompia Hospital, Dr. Renato Favero, who’ve got in touch with Isinnova through a doctor from the Chiari Hospital, the health facility for which we were manufacturing the emergency valves with 3D printing process. Doctor Favero shared with us an idea to fix the possible shortage of hospital C-PAP masks for sub-intensive therapy, which is emerging as a concrete problem linked to the spread of Covid-19
And the best you can do is identify another problem that it doesn't fix?
A ventilator is a machine with electronics, moving parts, and sensors that pushes air into people's lungs and pulls it back out. This is an improvised replacement for one of the less- or non-reusable accessories in short supply, the mask that goes on the patient.