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Posted

One of the significant factors in avoiding deaths due to Covid 19 is the lack of ventilators available as our health systems become overwhelmed.

Here is a short read that outlines the problem.

https://www.nbcnews.com/health/health-news/what-ventilator-critical-resource-currently-short-supply-n1168641

I put this in Engineering but let's not limit it to that. This certainly needs scrutiny from a biology perspective, and probably many others I can't think of.

Any suggestions as to ways to mitigate this problem? Also why they might not work...that could trigger a thought that could work.

I can certainly suggest ways to increase oxygen availability for interaction in the lungs but have limited knowledge of the way the body would react to it.

Even semi-effective suggestions could lead to freeing up ventilators from patients that might marginally need them for ones in more dire straits.

Oxygen tents? How about rooms with slightly elevated oxygen? How about turbulating the air that gets intaken? Warming the air taken in? 

Positive airflow from a tube to the bottom area of each lung? Move people to sea level? How about slightly hyperbaric? How? (ever been to a hockey rink/soccer field or other dome supported by air pressure?)

Other than reducing the spread of the virus to the more vulnerable...how can this problem be reduced?

In minimal time...should we watch Opollo 13 again?

If you were on your own in your house, but isolated from everyone, and knew you would need respiratory help from a ventilator within 2 weeks what would you do? How about the same time frame but more resources?

 

Posted

I think a good start would be to discuss how ventilators work and why they are needed, to get a better idea what functions a different system would need to have. In addition a better idea of the pathological profile of patients requiring ventilators would be needed. I am sure there is a range from folks having trouble breathing to those that are entirely dependent on mechanical ventilators as the lung does not compress properly anymore.

Posted

The ventilators are a 'treatment' for fluid in the lungs, or pneumonia, caused by the inflammation of the bronchial lining.
They don't treat the infection, but rather, the symptoms, which are what actually kills you.

The severity of the fluid build up in the lungs depends on a wide range of factors  ( age, smoker, asthma, etc ), the only one of which is related to the COVID-19 virus itself, is whether the infection occurs in the upper respiratory tract ( milder symptoms ), or lower tract ( worse symptoms ).

Posted

My rudimentary understanding was that they supported breathing by supplying air at a slight positive pressure. By responding to the natural breathing this would be at slightly greater for intake which normally takes more effort, and slightly less (but still positive) during air expulsion. They can also be used supplemented by higher oxygen, anesthetics, or other treatments. They do treat pneumonia, which can take place with the Covid 19 virus, by compensating in that manner.

https://en.wikipedia.org/wiki/Ventilator

https://www.theguardian.com/world/2020/mar/26/what-happens-to-peoples-lungs-when-they-get-coronavirus

Posted

James Dyson (vacuum  fame) designed a ventilator in 10 days and plans on making 15,000 of them:

https://www.cnn.com/2020/03/26/tech/dyson-ventilators-coronavirus/index.html

MIT has a designed an open-source ventilator:

https://www.technologyreview.com/s/615374/an-mit-team-hopes-to-publish-open-source-designs-for-a-low-cost-ventilator/

 

We have a couple supplied air systems at work for confined spaces. The simplest one is an ambient air system that supplies a controlled airflow to one or two masks (full face). Because the air is not compressed no real filtration system is required, just a simple dust filter (Our compressed air supply requires filtration to remove any oil that might blow by the piston)

These types of systems are not expensive, though their "controlled airflow" is just a setting, it doesn't respond to the cadence of breathing and uses valves to allow exhalation or excess airflow exhaust.

On the right setting, would this not facilitate breathing? 

 

Posted (edited)
19 hours ago, CharonY said:

I think a good start would be to discuss how ventilators work and why they are needed, to get a better idea what functions a different system would need to have. In addition a better idea of the pathological profile of patients requiring ventilators would be needed. I am sure there is a range from folks having trouble breathing to those that are entirely dependent on mechanical ventilators as the lung does not compress properly anymore.

Can you "expand" on that? (pardon the pun)

I thought compression of the lungs was less of a problem than expansion...as indicated by my belief a pressure very slightly above ambient would be net beneficial. When I relax I let air out.

Here's an idea that I think is pretty cool by a couple Canadian Engineering professors using both common household items and vacuum pressure to the chest (so the face doesn't even need a mask)

https://calgaryherald.com/news/local-news/alberta-professors-build-ventilator-prototype-using-shop-vac-home-depot-bucket/

image.png.ba5063cc2e98bbb66329ac8d64ffa91f.png

Here on the same with video: https://www.660citynews.com/2020/03/25/alberta-team-creates-breathing-machine-prototype-as-ventilator-backup/

Another advantage of this type of system, which would be potentially critical for anything below what would be typical hospital grade, is that in case of the system failing there at least is nothing to obstruct the breathing that the patient can muster on their own.

Any vacuum would only need to work hard enough to compensate for any leakage, so it could be extremely efficient for both energy used by the system as well as the effort from the patient, again assuming that lung expansion takes the majority of the effort to breath.

For Third World or remote applications, a decent seal could allow intermittent maintenance by a hand pump.

Edited by J.C.MacSwell
Posted

That of course assuming the simplest system that does not intentionally vary the pressure to the breathing cadence, to provide further assistance as necessary in some cases.

Posted

A positive system powered by a windshield wiper motor and built from plywood and common items:

 

It could also be used to assist breathing in a negative system (as above in the Canadian Engineers concept)

A windshield wiper motor is of course controllable to some extent using common parts. The key is getting the timing right to support breathing.

Posted
On 3/26/2020 at 5:53 PM, J.C.MacSwell said:

James Dyson (vacuum  fame) designed a ventilator

There is some suggestion that he should have asked someone who knew about them.
We don't need a new design- the things are complicated and our medical staff have enough to do without learning a new system.

He would have achieved more if he had got his existing factories to make the current design.

But, obviously, that wouldn't have got much publicity.

Posted
4 minutes ago, John Cuthber said:

There is some suggestion that he should have asked someone who knew about them.
We don't need a new design- the things are complicated and our medical staff have enough to do without learning a new system.

He would have achieved more if he had got his existing factories to make the current design.

But, obviously, that wouldn't have got much publicity.

I can see the optimal designs (ones that get feedback from the patient's breathing and require precise controls) being somewhat complicated to Engineer, but I would assume their use would (or should) be fairly intuitive to any medical staff with experience using current designs.

I would also assume they would use standard disposable breathing tubes etc.

Did Dyson make his more complicated or substantially different to use?

Posted
6 hours ago, John Cuthber said:

There is some suggestion that he should have asked someone who knew about them.
We don't need a new design- the things are complicated and our medical staff have enough to do without learning a new system.

He would have achieved more if he had got his existing factories to make the current design.

But, obviously, that wouldn't have got much publicity.

Is  it possible his factories were not equipped to manufacture the current design? Is there only one current design? Is it difficult to learn the new system?

I have no idea and am just curious if this was in part a publicity stunt as you suggested.

A quote from Dyson suggests a new design may have been in order.

Quote

"This new device can be manufactured quickly, efficiently and at volume," Dyson added, saying that the new ventilator has been designed to "address the specific needs" of coronavirus patients.

 

Posted
8 hours ago, John Cuthber said:

There is some suggestion that he should have asked someone who knew about them.
We don't need a new design- the things are complicated and our medical staff have enough to do without learning a new system.

He would have achieved more if he had got his existing factories to make the current design.

But, obviously, that wouldn't have got much publicity.

Agree. As far as I'm concerned, he designs lifestyle products and is not an inventor per se.

Posted
31 minutes ago, John Cuthber said:

OK, nor is the local jam making factory; but they aren't trying to get a govt contract.

Sorry but I missed your point. Do they have the capability to build the current design or not?

32 minutes ago, John Cuthber said:

are you aware of this issue?

What is the issue? They were asked to build ventilators then the govt. changed their mind. How does this relate to Dyson?

Just read on Quora (so can probably be taken as hearsay) that today's machines based on the original 1983 design cost between $60k and $140k. That is because of redundancy, testing requirements, intubation requirements, and all the other bells and whistles. What is needed now are fast, simple, cheap machines that can be quickly produced and meet basic functionality needs (which is mostly what is needed now). Hence, the need for a new design.

Posted

My dad died of Pulmonary Fibrosis over a decade ago.
This is a thickening of the pulmonary lining, and has a similar effect to excessive mucous slime produced in your bronchial passages and alveoli of the lungs. The mucus is produced as protection and lubrication due to an inflammation ( the Covid-19 virus ). Both cases restrict the passage of O2 from the lungs into the bloodstream, and CO2 from the bloodstream back into the lungs.

For the last several days, after his lungs had failed completely, my dad was on forced ventilation.
O2 is forced, under pressure, through the thickened lining, into the bloodstream, so you do not die of O2 depletion.
You die because there is no method to get the CO2 out of the bloodstream.
As the CO2 levels in your blood rises, it acidifies the blood ( carbonic acid ? ) until you die.

People with weak hearts/lungs or severe symptoms ( pneumonia, not bronchitis ) often succumb to this effect before their body has a chance to fight off the viral infection. The ventilator, in effect, buys you time.

I use beta-blocker drops to reduce ( and promote evacuation of ) the aqueous humor in the front part of my eyes ( Glaucoma pressure reduction treatment ).
Would some sort of beta-blocker treatment. administered through an inhaler, reduce the mucus build-up, clear away symptoms of pneumonia/bronchitis, and reduce the need for ventilation ?

Or am I totally out to lunch with my thinking ?

Posted
13 hours ago, MigL said:

My dad died of Pulmonary Fibrosis over a decade ago.
This is a thickening of the pulmonary lining, and has a similar effect to excessive mucous slime produced in your bronchial passages and alveoli of the lungs. The mucus is produced as protection and lubrication due to an inflammation ( the Covid-19 virus ). Both cases restrict the passage of O2 from the lungs into the bloodstream, and CO2 from the bloodstream back into the lungs.

For the last several days, after his lungs had failed completely, my dad was on forced ventilation.
O2 is forced, under pressure, through the thickened lining, into the bloodstream, so you do not die of O2 depletion.
You die because there is no method to get the CO2 out of the bloodstream.
As the CO2 levels in your blood rises, it acidifies the blood ( carbonic acid ? ) until you die.

People with weak hearts/lungs or severe symptoms ( pneumonia, not bronchitis ) often succumb to this effect before their body has a chance to fight off the viral infection. The ventilator, in effect, buys you time.

I use beta-blocker drops to reduce ( and promote evacuation of ) the aqueous humor in the front part of my eyes ( Glaucoma pressure reduction treatment ).
Would some sort of beta-blocker treatment. administered through an inhaler, reduce the mucus build-up, clear away symptoms of pneumonia/bronchitis, and reduce the need for ventilation ?

Or am I totally out to lunch with my thinking ?

Sorry to hear about your Dad. I hope any relatives in Italy are safe.

I don't know much about beta-blocker effects on mucus but it does seem that mucus is a double edge sword, protecting compromised areas but sometimes also creating conditions for pathogens to multiply and restricting the O2 and CO2 transfers as you said. Removal seems to be beneficial generally. Isn't that why we cough? But we keep producing more. Ideally ventilators assist in the process of mucus removal (to whatever degree is helpful) as well as increasing airflow to compensate for the reduced lung capacity.

 

 

Posted
14 hours ago, MigL said:

Would some sort of beta-blocker treatment. administered through an inhaler, reduce the mucus build-up, clear away symptoms of pneumonia/bronchitis, and reduce the need for ventilation ?

Or am I totally out to lunch with my thinking ?

No.
A similar approach is used with drugs to thin the mucous. (Probably not beta blockers but...)

https://en.wikipedia.org/wiki/Mucoactive_agent

16 hours ago, zapatos said:

Sorry but I missed your point. Do they have the capability to build the current design or not?

I don't know.

But, if they can, they should. If they can't they shouldn't be taking the taxpayers' money.

Posted
1 hour ago, John Cuthber said:

I don't know.

But, if they can, they should. If they can't they shouldn't be taking the taxpayers' money.

So Dyson shouldn't take the taxpayers money if they cannot build the current design. I don't understand why but I get your point.

 It just seems a shame to pass up any offers of help if they do indeed have a design that will do the job. Same goes for all the other designs JCM has been showing us.

  • 3 weeks later...
Posted
On 3/26/2020 at 6:53 PM, J.C.MacSwell said:

James Dyson (vacuum  fame) designed a ventilator in 10 days and plans on making 15,000 of them:

https://www.cnn.com/2020/03/26/tech/dyson-ventilators-coronavirus/index.html

 

Maybe more accurate to say that the Dyson company worked with a medical technology company to develop a new ventilator.

I read an article about how the UK decided that, instead of getting manufacturers to license designs of existing ventilators and manufacture them (they could have either paid the license fee or mandated that it was waived), decided that they would encourage manufacturers to come up with their own designs. Based on a fairly dubious spec from the government, which has since been rejected as inadequate by medical specialists. Never mind the extra time needed for testing and certification. Crazy, but typical of the "we don't need experts; how hard can it be" attitude of the current bunch of Eton clowns.

EDIT: yes, the article that John Cuthber posted!

Posted
2 hours ago, Strange said:

Maybe more accurate to say that the Dyson company worked with a medical technology company to develop a new ventilator.

I read an article about how the UK decided that, instead of getting manufacturers to license designs of existing ventilators and manufacture them (they could have either paid the license fee or mandated that it was waived), decided that they would encourage manufacturers to come up with their own designs. Based on a fairly dubious spec from the government, which has since been rejected as inadequate by medical specialists. Never mind the extra time needed for testing and certification. Crazy, but typical of the "we don't need experts; how hard can it be" attitude of the current bunch of Eton clowns.

I'd wondered about that claim. DIY plans exist that could presumably be adapted to utilize Dyson parts, but was thinking something hospital-ready would take longer.

Posted

The issue here is you can’t just blow air into and out of the lungs willy nilly. The body’s autonomic nervous system will still be trying to breathe on a rhythm, and serious failures will occur if the ventilator is not adaptive to those rhythms and adjusted as they change every 15-20 minutes. Ventilators require a lot of oversight and adjustment. 

Posted
3 hours ago, iNow said:

The issue here is you can’t just blow air into and out of the lungs willy nilly. The body’s autonomic nervous system will still be trying to breathe on a rhythm, and serious failures will occur if the ventilator is not adaptive to those rhythms and adjusted as they change every 15-20 minutes. Ventilators require a lot of oversight and adjustment. 

There is some truth that this may occur, however there are many sub optimal systems out there saving lives. I think (what I got from a number of sources including youtube explanations, some fairly detailed relative to my knowledge) the better ones default to a pre-set pattern when breathing is significantly laboured, ignoring any semblance of the patient's rhythm until it recognizes one that is sufficient to assist them. The simplest systems assist with an essentially constant pressure and flow rate, CPAP, with the mask exhausting the difference from breathing. Unfortunately this tends to aerosol the virus putting others at greater risk.

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