Open Source Ventilator Project • Hacker News Board

Re: Open Source Ventilator Project

#41

Post by ldng » Fri, Mar 20, 2020, 9:16 PM UTC

arcticbull wrote: post #38

ldng wrote: post #36

Earlier quoted context omitted.

You're absolutely right. But does it really matter ? A lot more ventilator are going to be needed, not in % but in hard cold real absolute number. Isn't that more important ?

A lot of ventilators and more importantly people to administer them . This project is not providing a ventilator, and it's not providing people the special training required to administer them. If we need ventilators, we can have ventilator companies produce them using emergency powers every developed country has.

Well, not everybody is The First World and have ventilators plants in their border. But some place will love to have access to free and unencumbered blueprints to be able to do something locally with what they have at hand ?

But you are also right that people are needed to administer those. No doubt about that. As is also true a person can administer several of those machines.

And, just because something tries to address A only (and not B and C), does not mean we should not do it because B and C. Separate issues. Beside, to train people, you need spares to train on.

Re: Open Source Ventilator Project

#42

Post by Mvandenbergh » Fri, Mar 20, 2020, 9:22 PM UTC

arcticbull wrote: post #8

Please, stop with these. As experts have shared many times on here, once you need a ventilator, the ventilator is the least of your problems. Trying to apply a ventilator to a COVID-19 patient who needs one when you have no idea what you're doing can create the same lung injuries as COVID-19 itself.

Just treat it as harmless hobbyism, which is what it is. When engineers are nervous, they build things. That is natural!

Will these open source designs save many lives? I doubt it. Large scale manufacturers working with existing vent makers will do a much better job. But... if it gets thousands of people thinking about artificial ventilation, we might get a lot of interesting new ideas that we can use in the decades to come.

Re: Open Source Ventilator Project

#43

Post by pbhjpbhj » Fri, Mar 20, 2020, 9:25 PM UTC

DoreenMichele wrote: post #26

whatshisface wrote: post #22

Earlier quoted context omitted.

> We have a core developer team publishing open source designs with ongoing communication with medical professionals regarding needs requirements, testing and validation processes. The developer team is led by OpenLung in Canada in collaboration with an Irish based engineering and operations team. The developer team is led by Trevor Smale, Dr. Andrew Finkle, and David O’Reilly from OpenLung as well as Conall Laverty…

I'm still not thrilled because hospitals actively breed antibiotic resistant infections. They are a primary source. Keeping invasive equipment adequately sterile is hard to do, even in a hospital. It's just the nature of the beast. To be clear, I'm extremely not thrilled at the global acceptance that "we need a zillion ventilators" instead of "we need non invasive alternatives and we need to educate the world as to w…

Non-invasive alternatives to "breathing for someone whose lung function has fallen below life-sustaining levels" sounds like [deadly] bullshit.

I'm not sure coughing in the shower is going to do it for someone about to die from hypoxemia?

Re: Open Source Ventilator Project

#44

Post by Mvandenbergh » Fri, Mar 20, 2020, 9:26 PM UTC

TaylorAlexander wrote: post #5

The page isn’t loading so I’m not sure what they’ve got, but I’m still trying to get answers to a question I have. I did research Tuesday and it seems like ventilators are positive pressure only, and they cycle between a low pressure and a high pressure. If this is the case, could an air compressor with a regulator be used as the pressure source? If so, a small device with just two pressure regulators and an electron…

To quote an earlier comment of mine:

So there are four main ways for breathing machines to be powered: 1) By compressed air from a wall port (majority of ICU machines)

2) With bellows (anesthesia machines)

3) Turbine, either dynamic or constant speed with a proportional valve (home use or patient transport)

4) Piston

Let's assume that we use a pneumatic device driven by centrally purified air as that is simplest. The parts then are:

-Gas blending to mix O2 and HP air. In many designs this is done using two solenoid valves.

-A fast, precise, and accurate proportional solenoid valve. This turns the constant pressure into the desired waveform

-another valve for controlling exhalation pressure. Can be another proportional solenoid, alternatively a manually adjustable valve to ensure constant minimum end exhalation pressure (PEEP)

-Flow sensor (range of options, typically variable orifice or hot wire anemometer but other type exist)

-Pressure sensor (silicon waver transducer)

-Overpressure valve

-O2 sensor (highly desirable, arguably you can estimate from O2 blending settings but that will work better on a very well characterised design which this would not be. Anyway O2 sensors are widely used so this will never be a constraint.

-Piping to connect it all together

-A control and alarm system to drive desired waveform based on user settings and sensors

-Patient circuit: Humidifier / heat exchanger, patient valve (one time use), viral filters for intake and exhalation air (one time use), ET tubes (one time use) Probably the limiting factor as far as parts go are the valves since this is a niche application. Here's the problem: as a civilisation, if we had to make a hundred million vents by the end of the year it would be easy. Expensive, sure, but not that hard in an emergency. It is much harder to make an extra 50,000 in a few weeks because it just takes time to turn the machinery of mass production in a different direction.

Let me know if you want me to send my list of ventilator reading. I'm not an expert either, just trying to soothe my Corona-madness by thinking about building things.

Re: Open Source Ventilator Project

#45

Post by senordevnyc » Fri, Mar 20, 2020, 9:26 PM UTC

chrisseaton wrote: post #40

ldng wrote: post #36

Earlier quoted context omitted.

You're absolutely right. But does it really matter ? A lot more ventilator are going to be needed, not in % but in hard cold real absolute number. Isn't that more important ?

> But does it really matter ? Yes - I think we should challenge misleading information wherever we see it in this situation. Fighting panic is part of the problem and bad numbers cause panic. I mean, if we don't really care that the numbers aren't accurate because it's more important to emphasise why the project is important, we might as well go all the way and say 99% of people need a ventilator and really sell the…

Actually, the biggest problem for a very long time has been people downplaying the risks and dangers of this pandemic, questioning the numbers, wondering whether it’s really that bad, and castigating any amount of preparation as “panic”, a word which has become meaningless in its overuse.

Re: Open Source Ventilator Project

#46

Post by twomoretime » Fri, Mar 20, 2020, 9:28 PM UTC

arcticbull wrote: post #33

twomoretime wrote: post #24

Earlier quoted context omitted.

> Inflammation can be combated with commonly available non drug remedies, like caffeine, lettuce, avoiding pro inflammatory foods (avoid peanut oil like the devil himself made it for you, limit or avoid bacon as it is hard on the lungs). This sounds like very suspicious folk advice, maybe based off a handful of data mined studies. I appreciate the tip about coughing up a lung though.

Many biologically active chemicals have been identified in nature. Aspirin (or at least salicylic acid compounds) is in wintergreen and willow bark. Opioids are derived from poppy sap, and eating too many poppyseeds will make you test positive for opium metabolites. Digoxin for heart failure and atrial fibrillation comes from foxgloves. Coffee, specifically, has tons of data pointing to it improving cardiovascular he…

I'm not denying any of that. What I'm saying is that when you randomly give a person a weak cocktail of random alkaloids and then ask them if they feel better, you're going to get a very unscientific mix of placebo and outright false information.

When you repeat such an experiment on large sample sizes with no control over the other myriad of environmental influences on the subjects, even after attempting to control for confounding factors you're still going to end up with extremely noisy data made effectively useless by just as many contradicting studies which find no effect. You see it all over the place - eggs and cholesterol, coffee harm/benefit, wine harm/benefit. These studies are all intimately highly flawed because they are empirical soft sciences with very little control over the large number of chaotic interactions among and within their subjects.

So when people say things like "drink coffee and eat lettuce to control inflammation during COVID infection" without a disclaimer, they're being [unknowingly] irresponsible, to say the least. Especially considering the dose of active compound in something like lettuce is likely to be totally insignificant.

Re: Open Source Ventilator Project

#47

Post by maxlamb » Fri, Mar 20, 2020, 9:28 PM UTC

chrisseaton wrote: post #40

ldng wrote: post #36

Earlier quoted context omitted.

You're absolutely right. But does it really matter ? A lot more ventilator are going to be needed, not in % but in hard cold real absolute number. Isn't that more important ?

> But does it really matter ? Yes - I think we should challenge misleading information wherever we see it in this situation. Fighting panic is part of the problem and bad numbers cause panic. I mean, if we don't really care that the numbers aren't accurate because it's more important to emphasise why the project is important, we might as well go all the way and say 99% of people need a ventilator and really sell the…

Yes, I’m sure lots of people in Italy, Paris and Madrid wishes they had spent more time/energy challenging the notion that ventilators are important as they are letting hundreds of people die every day because of the lack of ventilators. /s

Re: Open Source Ventilator Project

#48

Post by hackcasual » Fri, Mar 20, 2020, 9:29 PM UTC

labcomputer wrote: post #10

davidw wrote: post #7

Anyone pitching in seems like they're doing a good thing, but isn't the problem one more of political organization and scaling production? In other words, the US president (he is the only one authorized to do it) needs to activate the Defense Production Act, and get existing companies to mass produce existing designs. Something similar needs to happen elsewhere. This is a matter of days or weeks, not months. Please g…

My understanding is that the various open source ventilator projects are attempting to use readily-available COTS parts (by, for example, using a constant-speed blower and valves operated by RC hobby servos instead of a variable-speed blower). So that should, at least partially, solve the scaling problem. As for political organization, I would think that almost takes care of itself if someone presents a turn-key, sca…

So if these open source ventilators are needed in any number, it's going to be dependent on the RC hobby servo motor supply chain?

Re: Open Source Ventilator Project

#49

Post by dsl » Fri, Mar 20, 2020, 9:32 PM UTC

Mvandenbergh wrote: post #42

arcticbull wrote: post #8

Please, stop with these. As experts have shared many times on here, once you need a ventilator, the ventilator is the least of your problems. Trying to apply a ventilator to a COVID-19 patient who needs one when you have no idea what you're doing can create the same lung injuries as COVID-19 itself.

Just treat it as harmless hobbyism, which is what it is. When engineers are nervous, they build things. That is natural! Will these open source designs save many lives? I doubt it. Large scale manufacturers working with existing vent makers will do a much better job. But... if it gets thousands of people thinking about artificial ventilation, we might get a lot of interesting new ideas that we can use in the decades…

> Just treat it as harmless hobbyism

Any other time, yes. In a time of widespread panic? Dangerous.

People are going to try to build and use these at home in an act of desperation to "do something", and end up killing their loved ones.

Re: Open Source Ventilator Project

#50

Post by pbhjpbhj » Fri, Mar 20, 2020, 9:34 PM UTC

arcticbull wrote: post #25

tcbawo wrote: post #19

Earlier quoted context omitted.

Nobody knows the asymptomatic rate for certain, one way or the other. We don't know the rate of false positives with existing tests.

Fine, but we absolutely do know for an absolute fact that -- it is not true 15-20% of people with nCoV-19 need a ventilator. We don't know what the number is but we 100% with absolute certainty know it is not 15-20%. If we acquiesce to 70% of the US getting nCoV-19 as the epidemiologists are suggesting that would require 50 million ventilators. There are about 70,000 in the US. So we'd need almost 1000X as many venti…

Well in China they seem to have forced everyone to stay home?

The UK appears to have decided allowing 500,000 of us to die was a bad idea and we're now on "lockdown". At least everyone is _advised_ to socially distance, because - it seems - then businesses can still fire people for not turning up to work, and insurers can avoid paying out ("you chose to stop the event, you weren't obliged to").

I'm not sure we can tell what the rates are, what's the testing false positive rate? UK gave up testing a while back (except emergency hospital admissions).

For the last week, at least, all new cases here are in theory emergency hospital admissions. 700 cases per day (and rising), 10% of our normal number of intensive care beds.