There have been a lot of these 'open source ventilators', and they kind of miss the point. It's easy to make something that performs the basic functionality.
I have spent basically every waking hour of the last month and a bit working on a ventilator for my employer (part of Ventilator Challenge UK - project recently suspended). Making something that delivers air in the right duty cycle for breathing is easy. There's a few more things you want to do:
Blend O2 and Air ("FiO2"). Ventilators need to deliver Oxygen rich air to patients, but not usually 100%. Blenders are harder than you'd think to make. Note also that having pure O2 in your system means that there's a load of stuff you have to get right to prevent fire.
Alarms. This is the big one. most of the implementation (even taking account the next feature), was about checks and associated alarms, for blockages, failures etc. Making sure that we beeped loudly if something looked wrong. Note that 'not beeping' is a much WORSE failure than 'not ventilating'. If something goes wrong (including complete hardware failure of the ventilator), as long as a healthcare practitioner is aware and responds, then there isn't an issue. If the ventilator is happily ventilating away but something is obstructed then the patient might die (there are backup checks like pulse oximetry on the patient, but they're slow).
Assisted breathing. Driving a solenoid on and off at a particular rate and duty cycle gets you 'mandatory breathing'. That is great for keeping someone alive. If you're not unconscious though, it is both incredibly unpleasant and doesn't help you get weaned off and get better. What you want is a device capable of sensing attempted breaths and using the ventilation to 'help' them. This feature isn't 100% necessary - the early plans in the UK were for a massive shortage and for the simplest things we could get in a hurry. It quickly became clear that actually we needed ventilators to help people recover.
Yes. We spent as much time testing our alarm and monitoring system as we did doing gas delivery changes. And even on the gas delivery side, simple things like the patient changing positions while the ventilator delivered a breath could be damaging without following the standards explicitly. I think there are about 2 or 3 thousand different little functional requirements for building a ventilator. It took us about a year to get to first prototypes and then another year to get to the first passing of our system-level tests.
Even just our alarm system was very complicated, with cross-checking alarms and even cross-checking that the audio was indeed playing back. Things like playback tones and frequencies and alarm indicator colors and flash frequencies are highly regulated with relevant standards. And nuisance alarms are almost more important to avoid than having enough actual alarms. No alarm is as useless as the one the clinician turns off because it's the 4th time this hour it's gone off and the patient has been fine every time.
These are not easy devices to build, and selling something that doesn't meet the applicable standards and isn't substantially equivalent to something marketed today is unlikely to be particularly safe. You can easily do more harm than good by giving someone an untested ventilator.
Thank you for pointing it out. In addition to false-positives... it would really suck if a LED died, or a speaker died, and suddenly a critical alarm isn't going off. Redundancies upon redundancies are critical for these systems. The not cheap for a reason.
Man I felt bad for feeling this while reading the article. I've no doubt that Bill Dally is an awesome guy, especially given Nvidias recent excellent performance. But this project seems almost embarrassing. Why tout something on your corporate blog that's just a personal project of an employee he built in a couple of weekends. It looks simple enough for the final year project of a highschool student. I hate to be so negative, but I just don't see why nivida would associate with it.
Don't feel bad, you are likely a "glass is half empty" type of person, you can't help it. It's hard to believe you actually read the article, they framed the accomplishment in a very accurate light. They are not claiming it revolutionary: "Dally’s aim was to build the “simplest possible” ventilator." He accomplished this goal. He wanted to build a ventilator useful in emergency situations. Would you have us believe that on your death bed you would tell the doctor to give a ventilator of this design to someone else because it looks like a high school student could build it? This is a quality design because it meets the stated requirements.
If I were a glass half empty kind of person I wouldn't feel bad about it. Those guys are always gleefully pointing out flaws in things. I would not turn away anything a doctor would recommend I do, especially not on my death bed. In any case, there's been dozens of these solenoid based ventilators, and this one looks especially pretty, but if they were actually needed surely you'd hear all about hospitals using these diy things to save lives?
From what I've seen doctors actually talk about, is that there's ways to hook up even four people on one of those expensive type ventilators, and doctors still don't do it, because just giving people air isn't good enough.
The thing that makes me feel bad is this feeling it's some sort of off key joke. Maybe it has a use, but to me it seems like why is a big serious company like nvidia, making noise about constructing a ventilator that no doctor would use unless in an absolute emergency where they couldn't use a serious ventilator?
Alarms are critical, if you don't know that everything is working PERFECTLY then you don't know if one of your 20 patients is dying because of a failing $400 machine.
Also so is lifespam. It would suck to get all these ventilators that break down in a few days.
I've seen medical machine designs, and they have to check by the second that everything is working, and redundant systems so that if one system thinks all is well and the other doesn't big alarms start going on. And redundancy so that if part of the machine is failing the patient is kept alive while another machine is gathered. The quality is just as important as the function.
One of the items, of many, that worries me about this wild west season of ventilator innovation is that many of these new ventilators lack a common interface. Users are trained a long time on how best to use a ventilator using a very limited variety of user interfaces. I think it's very dangerous to expect a respiratory therapist to handle all the varieties of respirator interfaces that I'm sure are being created. New interfaces always mean mistakes, it's part of the learning process. We see it in software all the time. A user gets a brand new interface so it takes time for the user to acclimate to it. When you are dealing with a wordprocessor it's no big deal to make a mistake but a machine that can save or kill a patient depending on how it's being used is a whole different situation.
I can only speak for the UK regulatory environment here, but actually the situation is better than you might imagine. The best example is alarming - there are some common alarm patterns (the pattern you beep and flash your lights) for different priorities of alarm.
My understanding is that these aren't standrards you must adhere to, but because they're 'accepted' using them makes your life much easier with the regulators so everyone does unless they've got a good reason not to.
I appreciate the effort, but it looks like we aren't going to need nearly as many ventilators as expected because COVID lung problems are different than other lung conditions and seem not to respond well to invasive ventilation.
The video in particular is telling, highlighting the difficulty in getting a hospital to change what is considered the standard procedure in the face of new conditions (told by a frontline doc).
We are going to be up to our eyeballs in excess ventilators. Maybe they'll be handy for the next pandemeic ...
The report that you cite of 25% mortality for COVID patients on a ventilator is in line with COVID causing ARDS. There is currently no reason to believe that it causes some fundamentally different process from other ARDS-inducing diseases.
Our experience at MGH also puts severe COVID lung disease squarely into the ARDS category, and it responds to standard ARDS ventilation protocols[1]. Our mortality to date is shy of 20%.
From what I understood, with ARDS, it was necessary to medically induce a coma/paralysis and, in order to have highest chances of survival, required staff to monitor and posture patients every 8 hours.
Even if ventilator supply was not a constraint, would there be other constraints caused by staffing that would limit effectiveness of ventilators?
Note: I am NOT a doctor or involved in health or medicine in any way. My source for this information is this MedCram lecture on Youtube: https://www.youtube.com/watch?v=okg7uq_HrhQ
Staffing is definitely an issue as you point out, but what you’re describing is what would happen if we were to run into a capacity issue, which we likely would have without the lockdown but which we have not (at least, in MA).
> 25% mortality for COVID patients on a ventilator
That sounds more like the typical result for ventilators.[1]
I think it's more like 80% fatality on ventilators for this disease[2][3][4]. According to the published literature of course; I ain't that kind of doctor, but based on what is known, if someone comes near me with one of those things, well, they won't be a doctor for long either.
One of the articles that you’re citing (#3) had a correction due to a statistical error and they are now citing a ~25% mortality, not dissimilar to our data.
Theirs and ours may end up higher than they are now once the final patient is discharged, but the current US numbers are more like 20-25% mortality on ventilators at this point rather than 85%.
In the paper I see no direct comparison between COVID response to ventilation vs ARDS response to ventilation, but I think I understand that you say the responses are similar, based on your experience. Am I getting that right?
Also, of course, there is nothing in the paper comparing COVID invasive ventilation outcomes with, for example, oxygen and positioning treatment outcomes. So, interesting, but I don't think this qualifies as "data over anecdote".
I take it you are a pulmonary or ER doctor. If so, can you comment on the widely circulated claim that high death rates on ventilators in NYC are likely in part attributable to very aggressive ventilation and/or reduced attention to ventilation settings due to extreme fear of exposure to the virus (tubes leading from patients to other rooms and the like)?
Because of the high volume of patients, those of us with more critical care experience were redeployed to newly created MICUs, but I am not a pulmonologist (details in profile).
The high death rates in NYC that were published were attributable to a statistical error (failing to use adequate censoring of people still on ventilators). Note that the article has been updated with correctly censored numbers (hence 25%): https://jamanetwork.com/journals/jama/fullarticle/2765184
Finally, we only intubate patients after maneuvers like awake proning fail, so it’s not something that is comparable.
The study says ~25% died and ~70% remained at the hospital, shouldn't we assume that a percentage of those will also die and raise the final mortality figure?
Yes, I would certainly think that. Especially since given the timing of the article those on ventilators when the article was written probably had been on the ventilators for longer times on average, which doesn't bode well for them. Apparently a follow-up study is coming. I looked for it and did not find it yet.
My guess is that in the final analysis, NYC death figures for those on ventilators will be higher than they should have been (after adjusting for age etc.) The question then will be why.
But the real question, I think, is whether the death rates were higher than they would have been with less aggressive ventilator use.
Yes, I agree that seems likely. Because recovery seems slow (with and without ventilatory support), we won’t have a final accounting for quite some time. My point is more that the 85% number is considered an error and caused a correction in the published record.
That is not the UK experience. In the UK, ramping of manufacturing of existing ventilators has been more successful than expected, and social distancing has kept the demand on the NHS to a manageable level. Together that has meant that we haven't needed emergency designs.
Whether that is true in other countries is a different matter.
I'm not sure about developing countries, but I think by this point developed countries are probably on the right track to not need emergency-design ventilators.
That said, I hope the most promising of these designs get carried through to 'production-ready', in case we get hit with something even worse than COVID in the future, which is easy to imagine.
That's a somewhat cynical take, and I don't think any public policymakers would agree with your framing. What you're saying amounts to "We don't need more ventilators because all those people are probably going to die anyway and it won't save many lives."
A better reason is because we beat the outbreak. A few areas like Milan/Madrid/Brussels went past their health care capacity and could have used more hardware. But they're all past peak now, and everywhere else (almost -- there are a few worrisome spots in the US still growing, and the developing world is still a big question mark due to lack of testing) managed to reach peak without hitting their limit.
That's good news. We won. It's certainly not a problem that some of the efforts turned out not to be needed. It's like a war effort: everyone had a part to play, we needed to be conservative with our risk analysis and try different things.
It's widely accepted and known that fatality rates once you're put on a ventilator (due to Coronavirus) is ridiculously high compared to when you're put on a ventilator for other illnesses (something like 80% vs 20%). It suggests that ventilators might not be the right solution to what's happening to these people. So some doctors have been questioning the wisdom of continuing to use ventilators, and some doctors have been looking to alternative solutions that might have more success and better outcomes. One idea that was floated was CPAP (though I don't know what happened to that).
Nobody here is saying "ah, ventilators aren't working, fuck it, let everybody die". That's offensive to everybody here and a bad faith argument that isn't constructive in any way.
The 80% number is from New York. It's not borne out by other regional data. And again, if ventilators don't help someone needs to explain why the death rate in Milan shot through the roof when they ran out of ventilators. We just don't know yet.
As for offense: I apologize again. But the "ventilators don't work" take is getting too much traction among people who do make that argument, and IMHO it needs to be shut down. It's not good science. Not yet. Let the doctors do their work.
I'm not sure it's accurate to say we "beat the outbreak". First, it's a common opinion among experts that a second wave will emerge. If we declare victory and don't prepare, there's no reason it can't be much worse.
Second, at least in the US, it appears things are slowly gaining steam in more rural areas where healthcare is much more thin on the ground. At the same time, there's a push to reopen things, especially in states the skew more towards rural. It might not end up amounting to much, or it could be a disaster in the making, but it's not quite time to say "we won".
So... I agree with all that. It's not over. I just don't think enough attention is paid to just how outrageously bad things looked in late March. At the growth rates we were seeing, we'd have blown right through health care capacity and we'd have been looking at hundreds of thousands of US deaths by the second week of April. And it didn't happen. The growth stopped cold, because the lockdowns worked.
That's good news, and needs to be celebrated, so that we can continue the work. Instead, people on the left think "It's still serious!" and refuse to celebrate what we've achieved. And people on the right, not invited to the party, are being led to believe that the lockdowns somehow weren't the victory they actually were.
And that's bad. We won the war. The battles aren't over, but we know we can beat this.
I don't think you should make an analysis of our progress political. It does a disservice to "people on the right" if you think their opinions on the matter are somehow driven by left-leaning messaging. Such messaging has generally not, on other issues these past few years, done much to move right-leaning opinions. As such, if we're seeing people on the right are affirming opinions that you just "left", it should be much more thoughtfully considered as a legitimate, honest opinion, not one driven primarily by left/right messaging.
I agree that political generalizations often do a disservice to people on both sides, who often have their views caricaturized. When you say don't "make... political" do you agree that the cultural trends exist and are worthy of discussion in a conversation about handling the disease?
I think those are relevant topics of conversation. However, in the context of this discussion thread and the claim of "we won" over the virus, there wasn't previously a "left/right" framing of the issue. Adding it only after we were a few layers deep into the thread was unnecessary to the discussion of whether or not we had achieved victory over the virus.
It's problematic because it also didn't seem an accurate characterization of of opinion trends, which shouldn't have mattered one way or another in the conversation.
But my opinion that it wasn't an accurate characterization should not have been an issue in this thread at all: The introduction of politics derailed the discussion from one about progress against the virus to political rather than factual motivation for our opinions. Had the thread started out differently I wouldn't see that as much of a problem, though I think the introduction of political ideology into conversation on HN is often counter productive in general.
Thank you for clarifying, and so thoroughly as well. I suspected that this was the case. I was just curious because the line I referenced could have a range of interpretations. Thanks.
I think it's difficult to argue that it was "bad projections" instead of lockdowns that have made things better than projected. Because if it is wasn't the lockdown that helped, why has the virus behavior been so different in NY & NJ, but we didn't see outbreaks on the scale of NYC in other metro areas that had the benefit of seeing what was happening in those hotspots and acted accordingly? If the lockdown wasn't helping things, I would expect other densely populated areas to have had similar outbreaks. If the lockdown wasn't a significant determining factor, then we shouldn't be seeing hotspots in areas around the meat processing plants where the lockdown might as well not exist for the portion of the population that worked at the plant, and their families.
The models probably weren't perfect, but I don't think they were wrong in their general trends, even if the magnitude of those trends would have been slightly different in reality.
In any case, we'll know more in 2-3 weeks if things start to tick back upwards in areas that ease restrictions. Though even then, my concern is that the effect of lifting restrictions will occur too slowly and subtly, and so by the time we know there's a problem it will already be too late to easily contain.
> I think a big part of the conversation now is "how much was lockdown, and how much was bad projections?"
With all due respect: That's not a conversation among any serious academics. It's a conversation happening among political actors in political contexts (c.f. Tucker Carlson floating this two nights ago).
It's just not correct. And as you phrase it, it doesn't even make sense. "Projections" don't cause a change in R0. If you want to argue that this happened for some other reason than lockdowns you need to have a reason. And there are none that make sense.
(I mean, maybe it's herd immunity. In that case, why did the infection curves in different US states at very different death counts all bend the same way at roughly the same time after lockdown? Maybe it's weather: likewise, also the fact that the early China outbreak with similar behavior happened in the middle of winter. Maybe it's a mutant strain: nope, no particular evidence for specific ones having different behavior.)
If you want to have a conversation, you need to come to the table with a working theory. Social isolation has been known for centuries to work exactly the way it has here. It's a very attractive hypothesis, and is going to be difficult to disprove.
The question, maybe not debated among "academics" but debated among others, is whether spread rates ever would have gotten as bad in suburban and rural areas as they did in densely populated cities.
Models that used the same variables for NYC with population density of 30k people / sq mile as for rural states with tens or hundreds of people per square mile are just not realistic.
The virus is a serious threat. It's good that we took the actions we did. That is in the past. The question now is how we move forward. Part of that is gaining a better understanding of how bad the conditions on the ground actually are. All indications are that we can relax restrictions to some extent and still not overwhelm the hospital system. Indications also point that our current restrictions are absolutely catastrophic for the economy.
FWIW: the fastest growing US states right now are Nebraska, Iowa and Kansas (though Illinois is also up there, and no doubt dominated by the Chicago metro area).
The idea that rural areas don't see rapid growth isn't really well-founded. What happened was that large international cities experienced their outbreaks earlier. Nebraska may be small still, but at their current growth rate they'll match New York's all time high new infection rate (per capita) in just two weeks.
Go browse the charts at https://91-divoc.com/pages/covid-visualization/ and note how similar all these curves look. No one is special. Everyone grows rapidly without lockdown. Everyone levels off with it.
Only a few states have actually seen a peak and a significant reduction in new infections (c.f. Vermont, Montana, Hawaii). Those are the ones that might consider opening up right now. Everyone else just isn't safe yet.
I am in Iowa. I am aware of our situation here. It is highly localized to several meat processing plants. Bigger cities are seeing larger numbers.
I live less than an hour away from the capital, Des Moines. We have ~30 confirmed cases total in my county. My mom lives near the northern border. They have 2 confirmed cases total.
We never went to strict "shelter in place". Today the majority of the state is relaxing restrictions and restaurants can allow limited dine-in options if they wish.
Maybe it will go terrible. Maybe it won't. We will see.
> Maybe it will go terrible. Maybe it won't. We will see.
Would you have recommended that strategy to Lombardy in February?
I mean, you're citing current absolute statistics at a time when your infection count is growing rapidly. Your per capita new infection rate now is the same as New York's was on March 22. You understand that's not the right way to think about an epidemic, right? If you aren't flat then you're in the process of growing exponentially, and that doesn't just fix itself.
> Would you have recommended that strategy to Lombardy in February?
It seems you are willfully misinterpreting me. As you will see above, I said:
> The virus is a serious threat. It's good that we took the actions we did.
Things were much less known then. Now we have better ground truth and are less likely to be blindsided. I stand by my state's actions and decisions to date.
I have been exercising caution and following the recommended guidelines. I will continue to. I would guess most people here will as well.
We can't be in lockdown forever. The prudent thing to do, in my opinion, is to loosen restrictions slowly, being fully aware that we may have to tighten them again.
> I stand by my state's actions and decisions to date.
Your state's decisions and policies are producing rapid outbreak growth, though. Why do you expect that growth to change if the policies don't?
Going back to the link above, I see that Iowa's new infection rate (I'm looking at the 7-day average because per-day numbers are jumpy) has grown by a factor of 3.78 in the past 14 days. That's a daily growth rate of 10%, or a doubling period of a tiny bit over one week. At this rate, you will reach the same per capita rate that New York experienced at its absolute peak (April 9th) in just 13 days.
So... what's going to change in two weeks? Your curve isn't bending, your policies aren't changing. What's going to save you?
Here's what won't save you: locking down once things "get bad". Go back to the same site and see how long it takes from a lockdown until a state reaches peak. It's 10-20 days.
I mean, maybe I'm wrong. Maybe there really is some as-yet uncharacterized effect separate from lockdowns that steps in at the last minute just before states reach capacity to halt the outbreak. I just don't think Iowa should be betting on that, and I'm very scared about what we're going to see in the north central plains states in the comming month.
Why can't Wuhan or Milan or New York have been the control group? We've already run the experiment. We know how this works. Iowa doesn't look any different. It just doesn't. Iowa simply got started late.
You... genuinely don't think this is going to happen, do you? Even with the numbers above, you just figure something's going to change and you won't need to do anything?
You seem to be going out of your way to misunderstand what I am saying.
Iowa is highly locked down. We simply have not been ordered to "shelter in place".
Most of these restrictions remain in effect. The twenty counties that are experiencing outbreak growth remain completely locked down. The plan is to re-evalute and dynamically change restrictions as time goes on.
The official Coronavirus info page for Iowa is at [1].
Every county that has had restrictions lifted has experienced multiple weeks of declining case growth. Supposing they see an uptick in cases, measures will be re-instated.
It makes no sense to lock down rural counties that have seen zero or next to zero cases. Doing so will not ease the case load in the metros a hundred miles away.
I said nothing even approximately like "all those people are probably going to die anyway" and that is not, in fact, what I think! It is offensive that you would make up something like that and claim that is what I said.
What a growing number of doctors are saying is that ventilators often turn out to do more harm than good in treating COVID, ventilators have been used too soon and too often in treating COVID, and ventilators have probably resulted in excess deaths over alternative treatments.
I apologize if I offended you. That certainly seemed like what you were saying. The take is not new, and has been circulating among the "open up" community for a while.
As far as whether ventilators have "probably resulted in excess deaths"... that's just not justified by any science yet. We don't know. There's some suspicion in that direction, based mostly on New York ICU fatality rates (which are quite high despite otherwise good numbers through the rest of the process). But there's equally good evidence from e.g. Milan, which experienced very high death rates due presumptively to lack of treatment hardware.
I think the issue is coming up with a new protocol. Right now, it's not clear what should be don in lieu of ventilators. There are trials going on to see if oxygen alone has better results. I recommend the r/covid19 subreddit and medcram youtube channel for this sort of thing, by the way. They seem to be doing a good job of staying on top of new developments with proper references.
It was also pretty clear when people were pushing hard for ventilator production that they were a month too late once you consider even aggressive design, supply chains, lead time, etc. I doubt there will really be a surplus because a lot of these are under-tested and hastily assembled.
We've been a month+ behind on a lot of the response. Now's not the time to talk about ventilators, it's the time to start working out logistics of vaccine production and distribution.
I think this refrain is a bit over-simplified. TLDR it's a complex evolving situation, lots of uncertainty, insufficient specialists to handle the new influx, & no protocols around effective treatment leaving all doctors to do their best in the face of lots of unknowns.
Do we have sufficient ventilators for everyone who would need it? Probably. Are there not enough in practice? Yes. Why? We don't know how to differentiate between who needs it and who doesn't effectively. So people are getting put on them excessively to try to save the ones for whom it would help and we have no way currently to distinguish those people better. Should we fill this knowledge gap? Absolutely. I'm sure doctors & researchers are scrambling to do that.
> But Dr. David Hill, a pulmonary and critical care physician who treats COVID-19 patients in Waterbury, Conn. and serves as a volunteer medical spokesperson for the American Lung Association, says arguments against COVID-19 ventilation have been over-simplified. It may be less that ventilators aren’t the proper treatment for coronavirus, and more that they’re not a panacea for a pandemic that has pushed the health care system to its breaking point, Hill argues.
> “You have really sick people, [while] the people who have the best training are in short supply and ventilator management is not simple,” Hill says. If a dedicated lung specialist were available for each patient, he believes, outcomes would probably be better. They could make the subtle adjustments required for effective long-term ventilation, or try less-invasive options and only move to intubation when absolutely necessary. But with many hospitals nearly at capacity, last resorts can become first resorts.
> Few doctors are saying COVID-19 patients should never be ventilated, but there is a growing subset that thinks it’s happening too quickly.
<snip>
> Dr. Ken Lyn-Kew, a pulmonologist at National Jewish Health in Colorado, agrees that there are some differences between classic ARDS and COVID-19, but he emphasizes that there’s a lot of variation among COVID-19 patients he’s treated. He says most still meet the criteria for an ARDS diagnosis. In his view, coronavirus patients likely have ARDS plus other issues, but they still have ARDS. With so much unknown, and with treatment protocols being updated on the fly, he thinks it’s too soon for doctors to go off-book and avoid conventional protocols like mechanical ventilation.
> “The world is not a dichotomous, black-and-white place, but a lot of people are having trouble with that,” Lyn-Kew says. “We might be able to do better, but in the absence of data on the way to do that, we need to follow our societal guidelines and 25 years of research.”
> Traditional ventilators, by contrast, can cost more than $20,000
Traditional ventilators (ventilator) are very different from
bag valve masks, resuscitators, PAP and CPAP, BiPAP machines.
This Nvidia design is not alternative to that $20,000 hospital ventilator. It's emergency-response ventilator alternative these other cheap designs you can already order from Amazon. You can't keep people long time in this kind of device without serious risk of damage to the lungs.
Very few countries managed to produce emergency ventilators from scratch. Out of hundreds of ambu bag squeezer designs, find at least one that reached the assembly line.
Not a lot.
Only 4 countries on record now managed to start mass production of designed from scratch emergency ventilators.
Expanding existing capacity would've been an incomparably better option.
Check out Corovent, its somehow open source (they have to hide their exact BOM for now, because of companies buying full stock of those parts). It is build by university team that actually design ventilators for 25 years and is certified to be used in case when there are no proper ventilators available. They are currently using industrial version of medical parts (due to limited availability of those parts) but full certification is in pipeline. They are just starting mass production now.
One German manufacturer recently explained how their company has already outsourced almost all parts and manufacturing phases that can be easily scaled. The company does design, final assembly testing, calibration and quality control. I suspect that the internally used testing and manufacturing equipment and protocols are the hardest thing to scale.
The article did specifically say it is more advanced than a bag ("provides better care than “bag squeezer” emergency ventilators because it precisely regulates flow, pressure, and volume"). And it linked to the paper (http://op-vent.stanford.edu/docs/need.html) with more specifics. The "Prototype Specifications" section of the paper might be a good starting point for information about its capabilities.
Are your criticisms based on an understanding of how this specific device actually works? Sorry to be blunt, but by suggesting it is comparable to a bag valve mask, it sounds like you did not learn a lot about the device before making up your mind about it.
>Sorry to be blunt, but by suggesting it is comparable to a bag valve mask, it sounds like you did not learn a lot about the device before making up your mind about it.
Noting wrong with being blunt. But please, be blunt only after you read whole sentences and trying to decipher the meaning. I listed several different classes of devices of varying complexity that are not equal to those $20,000 ventilators used in ICU.
I have experience in design of electronics that becomes part of ventilators and other medical equipment. GE healthcare and other firms.
>Are your criticisms based on an understanding of how this specific device actually works?
Yes. The system in question is very low-end emergency-response ventilator (explained in documentation). It's simplified design from those you see used in emergency response and patient transport. The operating mode seems to be basic pressure-controlled ventilation PCV.It can also measure tidal and minute volumes.
ICU ventilator is device is very different from everything else. It's connected to the patients trachea. You must sedate patients because it's super uncomfortable to use. Patients are put into those ventilators when they are really sick. Removing carbon dioxide is an issue. Long term use can damage lungs so the system monitors large number of variables and it has multiple operating modes.
OK, I see a little better where you're coming from now. Knowing that you have some expertise in this area puts your first comment in a different light.
For what it's worth, I did read your comment carefully. The reason I took exception (and reacted strongly, I fully admit) is that since the article addressed the bag thing, that makes it a red herring, so I would have expected you to filter it out of your list. Maybe that's overly rigid or overly literal of me, but that is why I reacted how I did.
This device definitely intends to be less than a full-featured ventilator. On the Pneumatics page (http://op-vent.stanford.edu/docs/pneumatics.html) it explains their goal is to produce kind of a stripped down "simple ventilator with the features needed to treat COVID-19".
So they believe it can be useful even though they know it lacks features. Whether they're right is certainly up for debate. They mention several optional features, which is interesting because maybe it means they're just trying to be flexible or maybe it means they don't really know what is the minimum necessary to have a net benefit (save more people than you kill) if we run out of full-featured ventilators.
All these designs are cool projects but other than being a distraction and some PR nothing will come out of them.
There are plenty of proven designs that can be manufactured cheaply, the price of the end units especially for things like ventilators isn't often due to complexity and manufacturing costs but due to the costs of maintaining a supply chain, manufacturing and providing support (including liability) for the healthcare market.
None of these things seem to solve these issues other than potentially removing liability to who ever decides to manufacture those units.
Any thing can be built with off the shelf parts but the reason why most medical devices aren't it's because you need to take special care in your supply chain.
Ventilators use valves that aren't that different and often the same valves that are available for a plethora of other applications like industry and agriculture but the fact that it's the same valve doesn't mean that it's the same supply chain.
The suppliers for medical equipment make sure that say the lubricants that are used are safe and that no one can say replace o-ring used in the valve from one supplier to another without recertifying the entire thing making sure that the new o-ring meets the exact same specs.
For things like electronics then you have a whole other world of safety from things like resistance to liquids (anything from blood splatter to leaking IV bags), EMI to make sure it won't interfere with any other devices or be susceptible to interference on it's own and ESD to make sure there could no chance of sparks especially in devices that pure or high concentration oxygen can flow through or devices that will be near oxygen feeds.
And heck even if all that isn't the reason for ventilators being expensive and the true reason is IP Licensing/Patents then the US government and every other government can easily either compensate the IP holders directly or simply withdraw protection on the IP in question.
Many countries have already had legislation in place to allow governments to suspend IP protection or grant protection to violators during an emergency.
The effort towards the design of ventilators likely would have started when there was peak anticipated demand. The NY Governor was asking for 40,000 ventilators last month. So, we should not dismiss the effort.
There will be lots of wasted effort during the sprint to plug things in a hurry. But it may not be really wasted effort, given that projects like these can be fountainheads to unknown future innovations or relations.
Background: I design medical devices like this for a living and have for nearly 20 years. I also want to applaud the efforts of everyone working to leverage their professional experience toward helping us all through this.
I agree with this comment 100%. What the world needs now is more of the ventilators we already have designed, not new designs. With any new medical device comes a bunch of teething pains, finding and fixing bugs in the hardware and software design, training, testing andd iterative improvement of all these things as new issues are identified. All of this requires significant clinical support and companies that do this stuff typically employ dozens of clinically trained folks to aid in the introduction and development of the clinical aspect of the device. All of this time and effort is just not available now, any and all clinical resources need to be focused on treating patients, not helping engineers find bugs in their systems.
I believe this because an alternative exists, we do not need to reinvent the wheel, we just need more of the wheels we've already invented.
To be clear, I do however believe there is a lot of value in investing heavily and exploring all potential novel treatments and devices that could help fight this. I just don't see a value add to designing new respirators vs. Just making more of the designs we have now. I could be wrong, there could be significant manufacturing or other clinical advantages which i am not aware of.
We might need new ventilators, but we don't know what the requirements are until then our existing designs are better than anything new : we know they work and can be made. All we need is to scale production and that is much easier.
As we learn more we might discover things that make the current ventilators not optimal at which point it is worthwhile to design something new.
We know the requirements fairly well, we just need more ventilators not new ones.
The ventilators we have aren’t the problem and their cost and design also don’t impact the production capacity that much what impacts it is the fact that most medical manufacturers never had to operate on such scales and those that even come close tend to big the big international players with global manufacturing that is heavily reliant on China.
There is a plethora of designs for ventilators of all types from emergency CPAP machines to multi-mode life support for ICU’s.
Those designs have already been validated and there is a huge bank of knowledge to support them.
All these pump/turbine based respirator not to mention the pneumatic Ambu bag auto-squeezers don’t really bring anything new to the table they just introduce an untested hardware and software.
Like seriously half the ventilators that were shown were an ambu bag and actuator and a micro controller attached to some pressure sensor yes it’s a very simple respirator but do we really need 50 university teams coming up with a design variation?
And as far as discovering something new the only thing we discovered so far is that people were put on a ventilator and even more so intubation way too early and that has negatively impacted their survival rate which is one of the reasons why the demand for ventilators has dropped.
None of that contradicted anything I said. Maybe we will learn something tomorrow that means a new ventilator design would work better, but until then like you say, there is no need to design any when the existing designs work.
Everyone of these ventilators is basically an existing design just with different off the shelf components.
None of these projects created a new design or a new ventilation mode.
The vast majority of these are CPAP machines some maybe able to provide APAP in firmware.
If you look at the designs they are basically split into two categories the ambu which just basically compress an off the shelf ambu bag with an actuator or pump/turbine based machines that are essentially very similar to those which are given to people suffering form sleep apnea.
I don’t think there is even a ventilation mode we haven’t thought of yet even the most advanced ventilator on the market are mechanically very simply machines the cost is usually based on the brand and which modes they support.
This isn’t a field in which you can have a major breakthrough and not to dismiss this effort it’s not a field in which a breakthrough is needed.
Ventilators are cheap by medical standards even at $20,000 a pop the cost isn’t the issue the issue is that simply we never needed to produce them at such quantities in such a short time frame and for that you don’t need a new design you just need to accept that you aren’t going to reinvent the wheel and just take a proven design and make more of them and sort the licensing after this.
The fact that some teams had a working prototype within a day should be a very strong indication that there isn’t much here.
Having a turbine and a microcontroller to set the positive pressure on the outlet or having it set up how many times per minute an ambu bag should be compressed and at which rate isn’t a particularly difficult engineering challenge to conquer.
This is why there are now 100’s if not 1000’s of virtually identical designs out there from various teams across the world.
Yes anyone can build them in their garage and yes if the world have ended it would’ve been better than nothing but we have real options out there that can be just as easily manufactured if we actually had the will.
Atmega328p and no Arduino boot loader? Jokes apart, it’s pure inspiration to see someone like Bill Dally work out of his garage on a project like this. Kind of reminds me of Jim Williams a rekmowned apps engineer from Linear Tech who pretty much created the apps engineering discipline. Anyone willing to roll their sleeves and learn OpAmps/ADC look no further than App notes on Linear Tech website
We should be careful here. Smarts and creativity go a long way, but they're not a substitute for the years of training and experience of health-care professionals. Other commenters have mentioned delivering mixtures of gas as a requirement. I'll add sterilizing the equipment between uses.
It's true that the durable medical equipment (DME) industry is ripe for disruption. But that disruption isn't going to come from cheap stripped-down equipment, even if that equipment has stunningly wonderful software in it.
DME industry disruption will come from figuring out how to break the innovation-restricting stranglehold of Group Purchasing Organizations on health care supply chains. That's harder to pull off than quick-turn prototypes. What's needed is market disintermediation. That's a political and financial challenge, not a gadget-creation challenge.
Somebody once said to me, "software is the most complex thing ever invented." But that can't be right: look at a modern airplane. It has software in it, but it has plenty of other complexity. DME is the same way.
Creativity like Dr. Daily's is great. Really great. But it alone doesn't solve hard problems. If we software types claim it does, we're setting people up for disappointment.
All these designs should reduce the eventual price of ventilators after the COVID-19 passes. If we all know it’s not going to happen. The cheaper alternatives will be used to reduce manufacturing costs but they will keep the price same. That’s just how the medical industry works.
“The best minds of my generation are thinking about how to make people click ads.” –Jeff Hammerbacher
This is the kind of work I would like to see the best minds of my generation to work on.
I am not saying that I am one of the best minds of my generation, but I couldn't work for ad-network companies. I took consulting gigs only when I was trying to gain some big data exposure, and was in that field only for three years over three different occasions.
I would like to see more and more people to stop working for ad-tech companies.
I'm curious if these companies are OK with the risk that people make these devices, destroy their lungs, and then sue. It's great PR, but the previous systems were expensive for more reasons than just manufacturing cost.
Linux is a really bad operating system to use in this application. To do gas delivery safely and reliably you need to be using a Real-Time Operating System like QNX, VXWorks, OpenRTOS, etc..
I think it was a joke about NVidia actively working to make their cards suck on Linux. Besides: You could, especially now with real time capability moving into being a standard kernel feature.
To me the comment was neither cancerous nor ironic. We don't need to excise all humor from our discussions on HN. Humor itself isn't a problem -- though of course no joke appeals to all people.
>We don't need to excise all humor from our discussions on HN.
This isn't really relevant here, unless you are trying to create a strawman or frame this as a false dilemma of extremes. You can have a sense of humor while also keeping the conversation substantive.
[Edit: Assuming solar is correct: ]
Comments like the above are cancer when they inspire more of the same, and not long ago would have been appropriately dis-incentivized by the community.
[And if solar turns out to be wrong, then replying in earnest is still a good response.]
I have spent basically every waking hour of the last month and a bit working on a ventilator for my employer (part of Ventilator Challenge UK - project recently suspended). Making something that delivers air in the right duty cycle for breathing is easy. There's a few more things you want to do:
Blend O2 and Air ("FiO2"). Ventilators need to deliver Oxygen rich air to patients, but not usually 100%. Blenders are harder than you'd think to make. Note also that having pure O2 in your system means that there's a load of stuff you have to get right to prevent fire.
Alarms. This is the big one. most of the implementation (even taking account the next feature), was about checks and associated alarms, for blockages, failures etc. Making sure that we beeped loudly if something looked wrong. Note that 'not beeping' is a much WORSE failure than 'not ventilating'. If something goes wrong (including complete hardware failure of the ventilator), as long as a healthcare practitioner is aware and responds, then there isn't an issue. If the ventilator is happily ventilating away but something is obstructed then the patient might die (there are backup checks like pulse oximetry on the patient, but they're slow).
Assisted breathing. Driving a solenoid on and off at a particular rate and duty cycle gets you 'mandatory breathing'. That is great for keeping someone alive. If you're not unconscious though, it is both incredibly unpleasant and doesn't help you get weaned off and get better. What you want is a device capable of sensing attempted breaths and using the ventilation to 'help' them. This feature isn't 100% necessary - the early plans in the UK were for a massive shortage and for the simplest things we could get in a hurry. It quickly became clear that actually we needed ventilators to help people recover.