22 ms·

'Pandemic ventilator' could offer solution in potential 'worst case' scenario

161 points by iqster 7y ago

JohnBooty 7y ago
From the article: "We're talking about a device that we want to have available in the worst case conditions and strangely enough, COVID-19 is not the worst case envisioned," he said. Made me think. Perhaps in 3, or 5, or 20 years.... Maybe we'll be thankful that COVID-19 was sort of a "training wheels" pandemic... something that helped to prepare us for the even worse pandemics that are sure to follow. Deaths due to COVID-19 will be staggering, but it's somewhat mild as far as possible pandemic scenarios go. Imagine if it had mortality rates comparable to ebola, TB, etc. When this blows over, the world should be better prepared for the next one, with better procedures.... emergency stockpiles of ventilators, masks, etc. (Or at least we will be... until we go ten years without a pandemic... and all those stockpiles get liquidated in order to help some politician to balance a budget or whatever...)
- asdfman123 7y ago
  Well, it's so bad because it's generally so mild. More severe illnesses were able to be contained because they made people very ill before they got infectious. No one goes to work with a mild case of Ebola.
  - dredmorbius 7y ago
    A mild-onset-long-latency-ultimately-debilitating disease with high transmissibility might be a worst case. It could spread widely, evade detection, and not trigger immediate concern. HIV/AIDS, several hepatitis variants, and tuberculosis approach thiS, as might syphilis in earlier times. Kyle Harper's The Fate of Rome explores the notion that new diseases don't simply emerge, but co-evolve with their host populations and environments. The implications are disturbing. https://lareviewofbooks.org/article/how-the-environment-topples-empires-on-kyle-harpers-the-fate-of-rome/ https://lareviewofbooks.org/article/how-the-environment-topp...
- jmnicolas 7y ago
  > for the even worse pandemics that are sure to follow This is the first world pandemic in a hundred year, why should it become common ?
  - ashwoods 7y ago
    I think Climate change, population growth, travel, antimicrobial resistance are all good candidates in increasing the risk of this happening more often.
    - Roark66 7y ago
      Everything else, yes, but climate change? I can't imagine how climate change can significantly affect probability of next pandemic.
      - underwater 7y ago
        Displaced people? Displaced animal populations?
        JohnBooty 7y ago
        Also, warmer temperatures will benefit a lot of diseases in a lot of places.
  - nikofeyn 7y ago
    http://nautil.us/issue/83/intelligence/the-man-who-saw-the-pandemic-coming http://nautil.us/issue/83/intelligence/the-man-who-saw-the-p...
shaneprrlt 7y ago
Looks like similar portable ventilators already exist in the market: https://mfimedical.com/products/allied-healthcare-epv200-portable-ventilator-with-assist-control https://mfimedical.com/products/allied-healthcare-epv200-por...
- iqster 7y ago
  The key insight that made me want to post this is we should actively try to move to an older ventilator design (does bulk of the work, not optimized but easier and simpler). I have encountered this in my life as a software engineer. MFC (Microsoft Foundation Classes) in the mid 90s was hard to grok .. you had this huge book by Jeff Prosise to absorb. I cracked it when I chanced upon a manual for MFC 1.0. It was super simple and down to the essentials. All the fancy stuff they added from 1.0 to 5.0 was icing and made things complex. I think people who are actually working on ventilators should seriously consider going for a simpler design .. it might be this or might be something else. The person in this article also said he is happy to give the design away. I think if the Malaria Med+Antibiotics treatment from the French study don't work (we'll know in about a week I think), we need to move to a war footing and start producing ventilators. My back of the envelope math has scared the crap out of me (best case 500K Canadians dead, worse case 3 million). I really hope someone who can make a difference sees this.
  - arbuge 7y ago
    > I think if the Malaria Med+Antibiotics treatment from the French study don't work (we'll know in about a week I think), we need to move to a war footing and start producing ventilators. My back of the envelope math has scared the crap out of me (best case 500K Canadians dead, worse case 3 million). We should assume they won't work. War footing time is now.
    - iqster 7y ago
      Btw this article was an interesting read on trying to build a modern ventilator: https://www.wired.co.uk/article/car-manufacturers-ventilators https://www.wired.co.uk/article/car-manufacturers-ventilator... War time devices must be simpler (easy to make and do field repairs on). We just need the first one.
theamk 7y ago
This seems pretty important: > While the standard for a conventional ventilator uses a mask or nose tubes and follows current guidelines, the pandemic ventilator is at a standard from the 1970s and requires a patient be intubated, the medical word used to describe putting a tube through someone's mouth and into their airway. Do intubated patients need more attention from nurses/doctors? It certainly sounds harder then putting on the mask.
- tcbawo 7y ago
  Yes. Without proper cleaning, it is a highway for infection. You also need to maintain a balance of blood oxygen and carbon dioxide. Many of these people require supplemental oxygen. So, you have to control respiration rate and oxygen mix. This would be a very bad to try yourself.
  - monadic2 7y ago
    Intubation also reduces risk of of the patient infecting others.
    - catblast 7y ago
      Harder to infect others if you’re dead.
      - mirimir 7y ago
        Unless you plan ahead ;)
    - rtkwe 7y ago
      One of the other big issues hitting during this crisis beyond simple availability of ventilation machines is the number of nurses and doctors available to monitor and care for patients when they have to go to the ICU. Ideally the machine would be both cheap and easy to produce and require less qualified monitoring. If we get way more machines but those machines require a lot of intensive monitoring we could wind up with plenty of machines but not making any progress on the fatality rate.
swalsh 7y ago
I've been wondering, it seems like people have been setting up systems where multiple patients are connected to a single ventilator (with individual regulators?) If that works, maybe it might be more efficient to solve the supply problem, not by building a million cheap individual ventilitors, but rather a few thousand mega ventilators designed for multiple people.
- notatoad 7y ago
  Putting multiple people on one ventilator requires matching lung capacities, it seems like you can get away with 2-4 people on a ventilator if you really need to and have enough selection of patients to pick matching ones, but more than that wouldn't be feasible. (I'm not a doctor and my only source of knowledge on this is other hacker news comments)
  - enchiridion 7y ago
    I think that algorithms/ML people will have something to offer here. This essentially changes triage into a hard optimization problem. IANAD, but it's not just a problem of matching people in the current pool. You also have to plan for incoming patients. Having the parameters of the ventilator not perfectly match the patient likely affects the probability of survival in a smooth way (with in some bounds). So now the problem becomes minimizing the total death by maximizing the average likelihood of survival. You have to take the patient ventilator parameters into account (tidal volume, lung-compliance, weaning, etc) , as well as information about the distribution of those likely to be sick at the same time (which will change over time based on behavior).
    - numpad0 7y ago
      okay so how long does it take to certify that and how different is it going to be compared to just have General Motors produce under license on existing designs
      - enchiridion 7y ago
femto 7y ago
What about a "Both Respirator"? [1] In the 1930s polio epidemic there was a shortage of "iron lung" respirators, which were expensive to produce. Edward Both invented a plywood version, which was cheap and easy to produce. A re-purposed car factory then churned them out by the thousand. Is a negative pressure ventilator relevant for COVID-19 treatment? (Any knowledgeable medicos here who can offer a critique?) If so, couldn't they be churned out by the thousand in a short space of time (ie. days)? My understanding is that the tooling is comparable to that used to produce a kitchen cabinet. They can even be manually operated in the absence of a motor or control system. [1] https://en.wikipedia.org/wiki/Both_respirator https://en.wikipedia.org/wiki/Both_respirator
- thornjm 7y ago
  Med student here - so I know some of the theory only. The most relevant "law" is Fick's Law of Diffusion (https://d2jmvrsizmvf4x.cloudfront.net/CTU792sKR2evT2ezizQp_ficks-1498D1741D90BC0C7D21.jpg https://d2jmvrsizmvf4x.cloudfront.net/CTU792sKR2evT2ezizQp_f...). Doctors can increase diffusion by increasing the partial pressure of oxygen. In a diffuse infection a patient begins to lose both lung area (due to shunting) and the thickness of the diffusion barrier increases (due to inflammation). To help overcome this you want to increase pressure and oxygen concentration. An iron lung helps ease the work of breathing by reducing thoracic pressure and thus creates a larger pressure gradient for inspiration. However, it does not cause an absolute partial pressure of oxygen change compared to the atmosphere. Unfortunately, to bind haemoglobin in physiological lung conditions we need partial pressure of oxygen around 100mmHg. My guess is that an iron lung does not help increase the partial pressure of oxygen so it will do little but ease the work of breathing (which is better than nothing!).
  - FreeFull 7y ago
    You could always combine the iron lung with a mask that supplies oxygen.
  - totalZero 7y ago
    It's too bad we can't put sick people in an airplane, put oxygen masks on them, shut the door, and pressurize the cabin. Like a hospital, but at the airport.
pontifier 7y ago
I keep wondering if the Iron Lung is going to make a comeback.
- mirimir 7y ago
  They're for people with paralysis or muscle problems. And they'd be ~useless for COVID-19.
tcbawo 7y ago
If you read enough news and Twitter, you will find some really heartbreaking descriptions of the folks on ventilators. For most, this is a Hail Mary attempt with only 50% survival rate. Many will have significant lung damage if they survive. We need more ventilators to be sure. But we desperately need to find ways to halt the progression of runaway lung inflammation that leads to needing a ventilator. Edit: this development looks very promising for 'sub-intensive' cases -- adapting decathlon masks to provide positive air pressure (to help reinflate lungs) without intubation or leaking contaminated exhaust: https://www.isinnova.it/easy-covid19-eng/ https://www.isinnova.it/easy-covid19-eng/. Some emerging theories of pathology suggest that lung function can be increased by reinflating collapsed alveoli with constant pressure: https://emcrit.org/pulmcrit/cpap-covid/ https://emcrit.org/pulmcrit/cpap-covid/
- pmoleri 7y ago
  Interesting, so a little improvement there may lead to less ICU beds and sorter overall time at the hospital. Wonder if that's possible.
  - war1025 7y ago
    My understanding is that's the hope for Chloroquine and the other drugs being rolled out en-masse this week. They have shown enough promise by various limited trials that we are rolling them out nation-wide to see if they actually do help reduce the severity of the virus. If they do, then less hospitalization, and less ICU / ventilator needs. If Chloroquine doesn't end up working, basically we need to find something that does, because that is the only feasible way to get us out of this mess. We have shuttered the economy because the healthcare system can't handle so many people needing hospitalization. The only scalable way around that is to find a treatment that significantly lowers the need for hospitalization.
    - baxtr 7y ago
      At this stage it is totally unclear if Chloroquine will work. Unfortunately. Because, all the work published so far has not been produced through double-blind studies in randomized trials.
ta1234567890 7y ago
Is it possible to kill the virus inside the body, the same way we kill it outside? For example, if one could hypothetically spray alcohol everywhere inside someone's lungs, would that kill the infection? If so, could a liquid/gas mixture be developed to deliver the right virus-killer substance directly to the lungs? Does anyone here know about PFCs-breathing treatments?[0] 0: https://www.realclearscience.com/blog/2019/08/15/can_humans_breathe_liquid.html https://www.realclearscience.com/blog/2019/08/15/can_humans_...
- sudosysgen 7y ago
  That would also kill the person in multiple different ways at once.
- adrianN 7y ago
  We don't have anything that kills the virus but doesn't kill living tissue as well. Pouring alcohol over your hands is fine because skin evolved to protect you from a harsh environment. Pouring alcohol over mucous membranes is a very bad idea.
- ta1234567890 7y ago
  Why the downvotes? I asked a genuine question about potential alternatives. Thank you to the people that took the time to answer the question and explain why these ideas are not currently feasible.
eyeball 7y ago
Can a sleep apnea machine (cpap, bipap) help if you get it and run into problems?
- GoodOldNe 7y ago
  Yes, and in theory could be rigged to serve as a very simple ventilator.

161 points by iqster 7y ago

From the article: "We're talking about a device that we want to have available in the worst case conditions and strangely enough, COVID-19 is not the worst case envisioned," he said. Made me think. Perhaps in 3, or 5, or 20 years.... Maybe we'll be thankful that COVID-19 was sort of a "training wheels" pandemic... something that helped to prepare us for the even worse pandemics that are sure to follow. Deaths due to COVID-19 will be staggering, but it's somewhat mild as far as possible pandemic scenarios go. Imagine if it had mortality rates comparable to ebola, TB, etc. When this blows over, the world should be better prepared for the next one, with better procedures.... emergency stockpiles of ventilators, masks, etc. (Or at least we will be... until we go ten years without a pandemic... and all those stockpiles get liquidated in order to help some politician to balance a budget or whatever...)

asdfman123 7y ago
Well, it's so bad because it's generally so mild. More severe illnesses were able to be contained because they made people very ill before they got infectious. No one goes to work with a mild case of Ebola.
- dredmorbius 7y ago
  A mild-onset-long-latency-ultimately-debilitating disease with high transmissibility might be a worst case. It could spread widely, evade detection, and not trigger immediate concern. HIV/AIDS, several hepatitis variants, and tuberculosis approach thiS, as might syphilis in earlier times. Kyle Harper's The Fate of Rome explores the notion that new diseases don't simply emerge, but co-evolve with their host populations and environments. The implications are disturbing. https://lareviewofbooks.org/article/how-the-environment-topples-empires-on-kyle-harpers-the-fate-of-rome/ https://lareviewofbooks.org/article/how-the-environment-topp...
jmnicolas 7y ago
> for the even worse pandemics that are sure to follow This is the first world pandemic in a hundred year, why should it become common ?
- ashwoods 7y ago
  I think Climate change, population growth, travel, antimicrobial resistance are all good candidates in increasing the risk of this happening more often.
  - Roark66 7y ago
    Everything else, yes, but climate change? I can't imagine how climate change can significantly affect probability of next pandemic.
    - underwater 7y ago
      Displaced people? Displaced animal populations?
      - JohnBooty 7y ago
        Also, warmer temperatures will benefit a lot of diseases in a lot of places.
- nikofeyn 7y ago
  http://nautil.us/issue/83/intelligence/the-man-who-saw-the-pandemic-coming http://nautil.us/issue/83/intelligence/the-man-who-saw-the-p...

shaneprrlt 7y ago

Looks like similar portable ventilators already exist in the market: https://mfimedical.com/products/allied-healthcare-epv200-portable-ventilator-with-assist-control https://mfimedical.com/products/allied-healthcare-epv200-por...

iqster 7y ago
The key insight that made me want to post this is we should actively try to move to an older ventilator design (does bulk of the work, not optimized but easier and simpler). I have encountered this in my life as a software engineer. MFC (Microsoft Foundation Classes) in the mid 90s was hard to grok .. you had this huge book by Jeff Prosise to absorb. I cracked it when I chanced upon a manual for MFC 1.0. It was super simple and down to the essentials. All the fancy stuff they added from 1.0 to 5.0 was icing and made things complex. I think people who are actually working on ventilators should seriously consider going for a simpler design .. it might be this or might be something else. The person in this article also said he is happy to give the design away. I think if the Malaria Med+Antibiotics treatment from the French study don't work (we'll know in about a week I think), we need to move to a war footing and start producing ventilators. My back of the envelope math has scared the crap out of me (best case 500K Canadians dead, worse case 3 million). I really hope someone who can make a difference sees this.
- arbuge 7y ago
  > I think if the Malaria Med+Antibiotics treatment from the French study don't work (we'll know in about a week I think), we need to move to a war footing and start producing ventilators. My back of the envelope math has scared the crap out of me (best case 500K Canadians dead, worse case 3 million). We should assume they won't work. War footing time is now.
  - iqster 7y ago
    Btw this article was an interesting read on trying to build a modern ventilator: https://www.wired.co.uk/article/car-manufacturers-ventilators https://www.wired.co.uk/article/car-manufacturers-ventilator... War time devices must be simpler (easy to make and do field repairs on). We just need the first one.

theamk 7y ago

This seems pretty important: > While the standard for a conventional ventilator uses a mask or nose tubes and follows current guidelines, the pandemic ventilator is at a standard from the 1970s and requires a patient be intubated, the medical word used to describe putting a tube through someone's mouth and into their airway. Do intubated patients need more attention from nurses/doctors? It certainly sounds harder then putting on the mask.

tcbawo 7y ago
Yes. Without proper cleaning, it is a highway for infection. You also need to maintain a balance of blood oxygen and carbon dioxide. Many of these people require supplemental oxygen. So, you have to control respiration rate and oxygen mix. This would be a very bad to try yourself.
- monadic2 7y ago
  Intubation also reduces risk of of the patient infecting others.
  - catblast 7y ago
    Harder to infect others if you’re dead.
    - mirimir 7y ago
      Unless you plan ahead ;)
  - rtkwe 7y ago
    One of the other big issues hitting during this crisis beyond simple availability of ventilation machines is the number of nurses and doctors available to monitor and care for patients when they have to go to the ICU. Ideally the machine would be both cheap and easy to produce and require less qualified monitoring. If we get way more machines but those machines require a lot of intensive monitoring we could wind up with plenty of machines but not making any progress on the fatality rate.

swalsh 7y ago

I've been wondering, it seems like people have been setting up systems where multiple patients are connected to a single ventilator (with individual regulators?) If that works, maybe it might be more efficient to solve the supply problem, not by building a million cheap individual ventilitors, but rather a few thousand mega ventilators designed for multiple people.

notatoad 7y ago
Putting multiple people on one ventilator requires matching lung capacities, it seems like you can get away with 2-4 people on a ventilator if you really need to and have enough selection of patients to pick matching ones, but more than that wouldn't be feasible. (I'm not a doctor and my only source of knowledge on this is other hacker news comments)
- enchiridion 7y ago
  I think that algorithms/ML people will have something to offer here. This essentially changes triage into a hard optimization problem. IANAD, but it's not just a problem of matching people in the current pool. You also have to plan for incoming patients. Having the parameters of the ventilator not perfectly match the patient likely affects the probability of survival in a smooth way (with in some bounds). So now the problem becomes minimizing the total death by maximizing the average likelihood of survival. You have to take the patient ventilator parameters into account (tidal volume, lung-compliance, weaning, etc) , as well as information about the distribution of those likely to be sick at the same time (which will change over time based on behavior).
  - numpad0 7y ago
    okay so how long does it take to certify that and how different is it going to be compared to just have General Motors produce under license on existing designs
    - enchiridion 7y ago

femto 7y ago

What about a "Both Respirator"? [1] In the 1930s polio epidemic there was a shortage of "iron lung" respirators, which were expensive to produce. Edward Both invented a plywood version, which was cheap and easy to produce. A re-purposed car factory then churned them out by the thousand. Is a negative pressure ventilator relevant for COVID-19 treatment? (Any knowledgeable medicos here who can offer a critique?) If so, couldn't they be churned out by the thousand in a short space of time (ie. days)? My understanding is that the tooling is comparable to that used to produce a kitchen cabinet. They can even be manually operated in the absence of a motor or control system. [1] https://en.wikipedia.org/wiki/Both_respirator https://en.wikipedia.org/wiki/Both_respirator

thornjm 7y ago
Med student here - so I know some of the theory only. The most relevant "law" is Fick's Law of Diffusion (https://d2jmvrsizmvf4x.cloudfront.net/CTU792sKR2evT2ezizQp_ficks-1498D1741D90BC0C7D21.jpg https://d2jmvrsizmvf4x.cloudfront.net/CTU792sKR2evT2ezizQp_f...). Doctors can increase diffusion by increasing the partial pressure of oxygen. In a diffuse infection a patient begins to lose both lung area (due to shunting) and the thickness of the diffusion barrier increases (due to inflammation). To help overcome this you want to increase pressure and oxygen concentration. An iron lung helps ease the work of breathing by reducing thoracic pressure and thus creates a larger pressure gradient for inspiration. However, it does not cause an absolute partial pressure of oxygen change compared to the atmosphere. Unfortunately, to bind haemoglobin in physiological lung conditions we need partial pressure of oxygen around 100mmHg. My guess is that an iron lung does not help increase the partial pressure of oxygen so it will do little but ease the work of breathing (which is better than nothing!).
- FreeFull 7y ago
  You could always combine the iron lung with a mask that supplies oxygen.
- totalZero 7y ago
  It's too bad we can't put sick people in an airplane, put oxygen masks on them, shut the door, and pressurize the cabin. Like a hospital, but at the airport.

pontifier 7y ago

I keep wondering if the Iron Lung is going to make a comeback.

mirimir 7y ago
They're for people with paralysis or muscle problems. And they'd be ~useless for COVID-19.

tcbawo 7y ago

If you read enough news and Twitter, you will find some really heartbreaking descriptions of the folks on ventilators. For most, this is a Hail Mary attempt with only 50% survival rate. Many will have significant lung damage if they survive. We need more ventilators to be sure. But we desperately need to find ways to halt the progression of runaway lung inflammation that leads to needing a ventilator. Edit: this development looks very promising for 'sub-intensive' cases -- adapting decathlon masks to provide positive air pressure (to help reinflate lungs) without intubation or leaking contaminated exhaust: https://www.isinnova.it/easy-covid19-eng/ https://www.isinnova.it/easy-covid19-eng/. Some emerging theories of pathology suggest that lung function can be increased by reinflating collapsed alveoli with constant pressure: https://emcrit.org/pulmcrit/cpap-covid/ https://emcrit.org/pulmcrit/cpap-covid/

pmoleri 7y ago
Interesting, so a little improvement there may lead to less ICU beds and sorter overall time at the hospital. Wonder if that's possible.
- war1025 7y ago
  My understanding is that's the hope for Chloroquine and the other drugs being rolled out en-masse this week. They have shown enough promise by various limited trials that we are rolling them out nation-wide to see if they actually do help reduce the severity of the virus. If they do, then less hospitalization, and less ICU / ventilator needs. If Chloroquine doesn't end up working, basically we need to find something that does, because that is the only feasible way to get us out of this mess. We have shuttered the economy because the healthcare system can't handle so many people needing hospitalization. The only scalable way around that is to find a treatment that significantly lowers the need for hospitalization.
  - baxtr 7y ago
    At this stage it is totally unclear if Chloroquine will work. Unfortunately. Because, all the work published so far has not been produced through double-blind studies in randomized trials.

ta1234567890 7y ago

Is it possible to kill the virus inside the body, the same way we kill it outside? For example, if one could hypothetically spray alcohol everywhere inside someone's lungs, would that kill the infection? If so, could a liquid/gas mixture be developed to deliver the right virus-killer substance directly to the lungs? Does anyone here know about PFCs-breathing treatments?[0] 0: https://www.realclearscience.com/blog/2019/08/15/can_humans_breathe_liquid.html https://www.realclearscience.com/blog/2019/08/15/can_humans_...

sudosysgen 7y ago
That would also kill the person in multiple different ways at once.
adrianN 7y ago
We don't have anything that kills the virus but doesn't kill living tissue as well. Pouring alcohol over your hands is fine because skin evolved to protect you from a harsh environment. Pouring alcohol over mucous membranes is a very bad idea.
ta1234567890 7y ago
Why the downvotes? I asked a genuine question about potential alternatives. Thank you to the people that took the time to answer the question and explain why these ideas are not currently feasible.

eyeball 7y ago

Can a sleep apnea machine (cpap, bipap) help if you get it and run into problems?

GoodOldNe 7y ago
Yes, and in theory could be rigged to serve as a very simple ventilator.