Substitute “MIT student” for “physicist”. It’s one of that institution’s super-powers, but it might not be applicable here.
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I agree with that. I was just assuming that the flow and pressure requirements would be really different. Could be it would work.
I’m in a university Bioengieering department and we started comparing designs, when the expert of building these devices stopped us and told us to focus on getting PPE together. These will kill people, not because they are poorly made, but because the survival odds on a ventilator are really bad with COVID. It was depressing to hear that no hospital would take on the liability of one of these without FDA approval or a waiver like GM just got for their machines.
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This may be the video you’re thinking of:
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The other issue being that patients need to be intubated and sedated the entire time they are on the ventilator, and the pressure settings and supplemental O2 settings balanced between helping and harming as COVID-19 patients need high pressures and high O2 levels but both of those are also harmful - this isn’t something people can do at home, not even if they had a proper ventilator.
IANADr
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On the other hand, maybe oxygen gear intended for high altitude flight could be used to assist people with breathing problems due to covid.
Supplemental Oxygen is way more common and less complicated than ventilators. I haven’t heard of there being shortages of O2 systems the way there are for ventilators such that we’d need to cannibalize aviation systems for parts - but not hearing about something doesn’t mean it isn’t a problems, so I don’t know.
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I’m a trifle surprised that I haven’t heard any of the proposals for liquid based ventilators pop back up. People have been prodding at the idea since at least the early-mid 90s; and in principle it is quite attractive: relatively high molecular weight perfluorocarbons are relatively inert, dissolve enough oxygen that you can actually breath them; and have the great virtue of being denser than water, so fluid in the lungs can be made to float up, actually recovering usable volume, rather than going down the risky path of higher oxygen concentrations or pressures, with the risk of damage, to try to make do with what you have left.
Given that it’s been kicking around in testing for north of two decades, without clinical application, I assume that there are some nasty gotchas with the plan; but I’ve not heard what they are.
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At least in the US, supplemental oxygen is basically the equivalent of “take two asprin” for inpatients. It is used in a huge number of cases for a wide range of conditions – certainly anything involving respiratory distress. I would guess that most hospitals can supply oxygen to every single bed, so that probably won’t really be a problem until we run out of hospital beds. It does not, however, provide pressure to open the lungs, so it is not effective in more serious cases.
A next level treatment is CPAP and BIPAP. These provide air or oxygen at pressure to help hold open airways. However, the pressure is provided via a tight fighting mask instead of a tube into the lungs like a ventilator. These are used for both chronic conditions like sleep apnea, but also for acute respiratory distress that doesn’t warrant intubation.
The problem with CPAP and BIPAP for COVID19 is that the high pressure and tight but imperfect seal on the patients face tend to aeresolize the patients saliva as well as any viruses floating around. These aerosols can last hours in the air compared to the much larger respiratory droplets that come from talking or coughing. This is at least one theory for the nursing home outbreaks in Washington: a couple of patients have respiratory issues, and they are put on a CPAP machine to aid their breathing, and that helped the virus so quickly spread throughout the facility.
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One issue that hospitals have been encountering is that while they are designed to supply oxygen to any bed, the systems cannot cope with supplying a high level of oxygen to every bed.
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I have it on good authority that there has been a sudden interest in research done a while ago where I used to work. https://apps.dtic.mil/sti/pdfs/AD0680197.pdf
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Liquid based ventilators solve one problem (evacuating fluid in the lungs) but then present an even bigger one: Making people with diminished respiratory function have to work even harder to get enough O2. Lungs are not gills (quite the opposite really) and breathing liquids would take much more effort and trying to assist would pose the same problems and resulting issues that the cut-rate respirators like the MIT respirator doesn’t solve.
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I hate to bring it up, but in application, the intubation and sedation would be the limiting factor here. There is a pretty cool non-invasive “helmet” type device that could bypass the intubation part, but sedation would still be an issue, and I do not think the helmet do-hickey is widely available (like, at all) yet.
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I thought a key aspect of intubation was getting that tube down past where respiratory and alimentary diverge. Seems a sealed helmet system would also be inflating the stomach? Or is it not quite that simplistic?
Good point. Even CPAP can cause aerophagia, I guess the side effects of aerophagia are considered acceptable in the case of emergency ventilation? Dunno, but that does seem like an issue and I have no idea if they have some way to mitigate it. IANADr.
No, accurate thought. You would need to have an NG tube to decompress the stomach. Never said it was perfect! (IAADr. 
)
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Nurse reacts to Tesla’s ventilator & what’s with those resuscitators?
An excellent analysis of the various automated ambu-bag squeezers like the MIT project, and an informed look at Tesla’s report on their progress with in-house design and production of a full-featured invasive ventilator cobbled together out of car parts.
I’ve lost track of how many different automated bag-squeezers are out there - they’re such an obvious maker-hack. (The Mercedes F1 team’s design, optimized for high-speed manufacture, is a sleek piece of kit.)
As the video notes, an automated ambu-bag would be better than having to pump a bag by hand for hours on end, but it’s still only a marginally useful temporary stopgap.
Even Elon’s much-derided BiPAP machines are more useful, (esp. since they can be converted to basic invasive ventilators with the minor mods spec’d in the Northwell protocol (q.v.)
But it’s always good to see people trying to help.
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A Norwegian company launched a similar ventilator concept to this a week or two back, and it was quickly pointed out that this can in no way replace a hospital-grade medical ventilator. First off, a bag like that doesn’t generate the kind of pressure of a proper ventilator, which is necessary to aid breathing for those with severe pneumonia and respiratory failure. These bags are designed to provide short-term supplemental ventilation, not to replace your breathing entirely for long periods of time.
Second, proper ventilators monitor blood oxygen levels and other crucial metrics and adjust the levels of oxygen and other gases in the ventilator. Do these do the same? 'Cause without that, they are essentially worthless. Pumping ambient air into the lungs of someone with respiratory failure will not keep them alive, as their lungs are likely far too damaged/sick/inflamed to absorb sufficient oxygen from ambient air.
Tl;dr: there are no miracle cures, and there’s a reason why commercial ventilators are huge and complex machines.
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