Risky hack could double access to ventilators | Hacker News Reader

Risky hack could double access to ventilators

vice.com

257 pointsspookybones154 comments

This is really neat. It seems a lot of the risk is how specific lung capacities and conditions interact with the ventilator and how much oxygen someone needs. My question to any MDs reading this: how often do you have to tweak ventilator volume for patients using one? What is the feedback loop? Blood oxygen levels?

(physician here) Vents can be quite tricky to get right; primarily because as disease progression continues on many things change. We are always trying to balance the deleterious effects of the intervention (in this case, the vent) with the goals of care.

What most people don't know is that vents cause a lot of injuries on their own. (See ARDS). Hypoxemic respiratory failure is serious stuff, and it's almost always not the only insult we're dealing with. So, it's about balance.

In the feedback loop is a lot of things. Certainly, oxygen saturation is a core measure, but we are also thinking about things like hypercapnia (and acidosis); overall perfusion status (blood circulation); infection management; etc.

Gas exchange is important, but there are a lot of things that have to go right for the lungs to take oxygen in, get it into the right transport, and get carbon dioxide back out. You can over-optimize for any of those at the expense of the other (see: hypercapnia).

In short, it's complex and there isn't a solid formula that will work for every patient. It's actually the subject of a lot of debate on details (some of it quite passionate in our Critical care / pulmonology community). This is why we call it PRACTICING medicine ;)

What do you think are the risks of cross contamination in this setup (let's say, just for 2 people sharing one unit)? She mentions how, in a situation where you'd have to use this, they'd have the same infection. What if they have different secondary infections or different types of pneumonia?

The example of the Vegas disaster is different because they were all gunshot victims; they were healthy, but wounded. I hope we would never need to see if these would be effective.

MD here. There is an inhalation and exhalation tube for each patient; the exhalation tubes would be in continuity using the described configuration. However, at least for part of the transmission route, viral particles would have to move against flow. So there is likely some cross-contamination.

All that being said in the situation where this is deployed I think it would be a risk most providers would take.

Thanks for this explanation.

I can't even figure out what my HVAC vents do, or how not to mess up my entire heating and cooling situation – so I leave them alone.

Utter respect for you and all the other medical professionals who are having to adapt and deal with this unfolding situation. Many thanks for what you do.

IANAMDOMP. After respiratory therapists, it seems like perfusionists will be stretched thin too because there are so few of them globally. I would predict lots of ECMOs and long waiting lists for lung transplants in the next few months, but also lots of poor outcomes for COVID patients with preexisting cardiopulmonary issues. I just hope young and middle-aged people take it seriously and don't avoidably waste healthcare resources through irresponsible behavior.

I've got a really naive/dumb question for you.

Could you use a CPAP machine as a poor man's ventilator? Would it be better than nothing?

There's definitely a ton of CPAP machines out there.

A doctor asked me that-- a fact I found disturbing, because shouldn't he know-- so I did some research. And I found out that the machine would spread the virus everywhere with the outgassing (I'm not sure if that's the right term).

There are way too many different brands and types of CPAP machine for anyone to make any sort of sensible comment here. They aren’t all the same. Some of them do have a backup rate that could be used to mandatory mechanical ventilation, but that can’t be readily altered at the bedside in the models I have used. The use-case is radically different to the ICU.

Interesting. This has been done before (after LV shooting) but has conventionally been considered as an intervention suitable for treating mass trauma. That's because people who are otherwise in good health are easier to ventilate than people with stiff, non-compliant lungs caused by inflammatory viral ARDS.

Ventilating people with ARDS is hard. You have to use low, carefully considered tidal volumes and essentially allow the patient to be hypercapnic (CO2 higher than ideal), sometimes quite severely. You're doing a delicate dance between ventilating in a way the lungs can take and maintaining blood gases compatible with life.

As you say, we have many patients already in our ICUs who need ventilation, but aren’t /difficult/ to ventilate.

Perhaps they could get the split ventilators and the COVID-19 patients could get their own?

Yes, but the demand projected for ventilators seems to exceed the entire existing supply, and obviously dwarf the uses for all other conditions combined.

Have governments made orders (legal or purchase) for manufacture of ventilators by large scale companies?

Presumably ventilators are a relatively niche product - what's in them that the World's industrial complexes can't ramp up production of within a couple of weeks?

I imagine it's the pumps that's the limiting factor? Given humanity already has the working tested, established designs.

Can't governments requisition the design, turn the original factories in to test only, or construct and test, centres. Instruct the mega-corps, publicly, which parts they are to make and by when ...

In the West we throw away tens-of-thousands of highly engineered products every day; surely we can step up now?

Reporting in the UK says that half a dozen prototypes have been delivered to the NHS for manufacturing approval already.

Half a dozen somehow sounds more impressive than six...

Hah, yes! Although six individual companies spinning up a prototype in quick order is pretty impressive as well.

Tangentially (this is HN after all) I also feel like "half a dozen" gives a more fuzzy confidence interval than a regular number ("6"). Of course, half a dozen literally means the amount 6, but am I the only one that reads them slightly differently? I almost see an implicit "about" before the phrase: "[about] half a dozen".

It's actually a really interesting subject, I think it's closely related to something called "words of estimate probability", the wikipedia article [0] is a good startingpoint.

0: https://en.wikipedia.org/wiki/Words_of_estimative_probabilit...

It's a technique you can use in software estimation too.

There's an implied difference between saying something will take about 2 months vs 8 weeks vs 57 days, even if they're all technically the same amount of time.

And we can assume that means 57 bank/gov't working days, which could easily be about 3 years. :)

Bigger scales typically include an implicit amount of wiggle within the lower scales. People understand that when you say a car cost "25 thousand", that it's not exactly 25,000, but that it's closer to 25,000 than 24,000 or 26,000.

Moving to a bigger scale, and then back down to a smaller scale maintains that implicit wiggle room.

I am not an expert on manufacturing biomedical devices, but I do know quite a bit about manufacturing safety-grade nuclear components. So take this with a grain of salt. However, from what I do know, fundamentally the requirements are pretty similar.

There is likely nothing magical from a purely mechanical standpoint about making a ventilator. The part that is difficult is:

* Have an adequate QA program for you and your suppliers, tracing safety-critical components down to the raw materials

* Adjusting your tooling, making molds, etc.

* Doing low-production runs followed by testing to validate your process

* Getting whatever certification is required; even if there is a flexible emergency process, I think we still want some demonstration of compliance

* Not having the lessons-learned of companies who have been doing this for years, and have worked through enough problems to have general domain knowledge

* etc.

My experience would lead me to believe that short-term returns would better come from finding ways to optimize the supply chain and manufacturing pipelines of existing manufacturers, which potentially could be done much more quickly.

If you look at the example of WW2, when auto factories converted to war production, it was not a quick or easy affair. The excellent book Arsenal of Democracy describes the conversion of the Willow Run factory to producing B-24s, it took at least a year and a half to get the plant producing planes at an acceptable quality and quantity.

> it took at least a year and a half to get the plant producing planes at an acceptable quality and quantity.

I wonder if this would be longer or shorter today with how much of car assembly is automated. How many of the tools do one specific thing a human used to? How many are robots that can be reprogrammed? That, and cars and ventilators are completely different. I'd think a ventilator is closer to a dishwasher than a car (think appliance).

I've had some experience with the robotics / automation engineering side of industry. It's not easy to take super high-level automation and turn around and make it produce something else entirely.

Base / core machinery- such as a 3-axis CNC machine, or a lathe, or a saw, for instance, are fairly nimble- if you have the right cutting bits (which you probably do, considering that it's industry) you can switch from milling out aluminum mounting plates to milling out enclosures for electronics fairly easily. At this level, generally humans are responsible for sticking in the material and telling the machine what to do each time an action is performed.

Where it gets more complicated is at the higher levels of automation, where humans might be supervising the machines, but aren't initiating processes themselves- for example, there was a prod cell that I worked with that had a robot putting raw material into a mill and then removing it- humans program those arms, but then after that, it just goes, and goes, and goes. Programming those arms is generally an exercise in making sure the math works, and then implementing the job in a bunch of for loops and hard-coded / static adjustment variables and the like. In these instances, to make the cell produce something else, not only do you have to program the machine that actually produces parts, but you also have to reprogram the bot that puts and pulls from it, and you may also need to change the grip on the bot to support the new geometry.

At the really high levels, like how car manufacturing is currently, there are processes where metal blocks go in and a whole monoframe chassis comes out. Taking that and saying "I want a ventilator assembly" is pretty much insane- besides reworking the entire line to support the new process, you've got to wire everything up, test it, inspect it, make sure everything is up to OSHA standards, etcetera etcetera, etcetera.

Going from producing one thing with a high amount of automation to another that doesn't have any similar parts is insanely difficult. Not saying it isn't worth it, but it might be better to go to the factories that are already producing the stuff we need- ventilators, masks, respiratiors, tests- and seeing if there are any bottlenecks that could be removed.

The best way? Have enough stuff on hand to actually handle a crisis. Too bad prepping for a rainy day doesn't really align with maxing out dividends and payoffs.

Germany ordered 10,000 ventilators from a domestic manufacturer, though with delivery "over the next year" so it's unclear what the schedule will be.

More like „within several weeks“...

https://www.welt.de/wirtschaft/article206603525/Beatmungsger...

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

-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.

In the UK, there's talk of Jaguar Land Rover, JCB and F1 engineering teams all making contributions towards the production of ventilators

I keep seeing people asking "Why can't we just quickly spin up technology X?" where this is here ventilators, otherwise vaccines, etc...

without much awareness of how much specialization goes into almost every aspect of every job. Hell, even fast-food workers-- a skilled grill operator at McDonalds -- take time to train up.

No, we cannot quickly undo the 20 years of systematic dismantling of our core infrastructure. We are in for a very rude wake-up call.

And then, once we are awake, and are dealing with our new realization on the complexity of our economy, where every part depends on every other part functioning, and trying to get this restarted with a significant number of the parts NOT working...

Then we realize that the economy is embedded in an even bigger system called "life on earth" which we have degraded and destroyed on a much larger scale than our economy.

If you think the weakness in our society which the virus uncovers are a big deal, you simply lack the full picture.

> I keep seeing people asking "Why can't we just quickly spin up technology X?" where this is here ventilators, otherwise vaccines, etc...without much awareness of how much specialization goes into almost every aspect of every job. Hell, even fast-food workers-- a skilled grill operator at McDonalds -- take time to train up.

> No, we cannot quickly undo the 20 years of systematic dismantling of our core infrastructure. We are in for a very rude wake-up call.

Wait a minute. I was with you up until the end of "...take time to train up.", but I've lost the plot between there and "No, we cannot quickly undo the 20 years of systematic dismantling of our core infrastructure." To me, these seem like two extremely different issues, but it appears that you see them as being ~equivalent, or am I misunderstanding?

> And then, once we are awake, and are dealing with our new realization on the complexity of our economy, where every part depends on every other part functioning...

Agree, but I just wanted to add my $.02: Be careful when using "awake" - this is a very, very tricky word. To say it can be be deceptive is a major understatement.

> Then we realize that the economy is embedded in an even bigger system called "life on earth" which we have degraded and destroyed on a much larger scale than our economy.

I see your point, but again: for specific definitions of "degraded" and "destroyed", maybe. And even if so, does this have bearing on this particular issue? If not, it should not be part of the analysis. It confuses people, and this situation is confusing enough.

> If you think the weakness in our society which the virus uncovers are a big deal, you simply lack the full picture.

I assume you meant "...are not a big deal..."?

Hey, thanks for the clarifications, and apologies to the community that I started ranting.

The equivalence between "takes time to train up" and "20 years of systematic dismantling" is that we have lost many of the experts we might otherwise depend on in a national emergency. For example, Trump dismantled the Pandemic Response Team. You can't easily replace that overnight. Longstanding cuts to CDC budgets, etc.

You are also correct that I was making a rather unexpected analogy between our current crisis and the environmental crisis. Yes, this would catch a reader off guard and cause the confusion you suggest.

Here it is again: The economy is a complex system. Each part basically assumes that the rest of the parts are there. Imagine Amazon without a postal deliver service, for example. Or your grocery store without a trucking industry.

Much of the global economy is now shut down. We will have to re-start it, which we will do, but it will be painful because of complex interdependencies between parts.

Here is the analogy: Life on earth is also a complex system. We have done our best to extract and destroy as much of it as possible. For example, insect populations are down by 80% in Western countries.

We take for granted that the natural environment is there, providing what it has always provided, without realizing how badly we have disrupted it.

Just as the US has taken good health for granted and dismantled things like the CDC, taken good roads for granted and not repaired them, taken good education for granted and demonized public school teachers (hello, Wisconsin!)....

> The equivalence between "takes time to train up" and "20 years of systematic dismantling" is that we have lost many of the experts we might otherwise depend on in a national emergency. For example, Trump dismantled the Pandemic Response Team. You can't easily replace that overnight. Longstanding cuts to CDC budgets, etc.

Do you have trustworthy (confirmable), conclusive data that suggests the ideas (assumptions) in this statement are actually objectively true, and materially relevant to the actual problems we are experiencing? I've read a billion claims of this, but literally every single time I interface with the person that wrote it, the response is angry and evasive. Literally 100% of the time. Note that I'm not strongly implying any conclusions here, I am simply pointing out what I think is an extremely interesting and important phenomenon that is currently occurring on our planet, and I think there is a causative relationship between the two.

I follow your new analogy, it makes perfect sense to me, but how you connect this back to your conclusions is where you continue to lose me.

I see creation of a vaccine very differently to production of one of a range of existing ventilators.

There are many companies using things like 6D CNC machines with high accuracy that can essentially spit out a part for which there's a definition (and we can 3D scan parts to micrometer accuracy with laser scanners); many electronics companies can make "any" circuit to some extent (I'm guessing ventilators use generic components, some circuits might be generic - like valve controllers, whatever, certainly display controllers I'd expect to be generic). Parts like keys, cases, outside the gas flow/control path are probably injection moulds that factories could pop out a million of within a week (once the dies are duplicated).

A skilled grill worker takes a while to train, but any grill worker given McDo's recipe could make you a functioning BigMac in an hour. I'm not asking for a new product to be designed (one effort - opensourceventilator.ie - are doing exactly that, making a modified BVM system).

Still looks like production could produce output in weeks rather than months.

The problem isn't production.

It's mass automated production. Once you take the human out of the picture to get a machine to do the work you've now involved a programmer, CNC operator, roboticist. and an industrial engineer at a minimum just to get the rough task doable.

We could probably have a fully human operated production line up and going relatively quickly, but getting the machines all cut over and integrated so as to do it themselves is hard.

Look, thought experiment. You ever watch that show, "How It's Made"? They literally make entertainment out of watching the end result of the final outcome of integrating all of these stages of the fabrication process.

But if you have ever watched it, did it not strike you as interesting that they never seem to do an episode with regards to the production of the very industrial equipment automating the fabrication process?

They can't/won't because it is bloody hard, error prone, and freaking expensive. Once you've got it, you're gold, but it is by no means a short route getting there.

The department of Department for Business, Energy and Industrial Strategy has put out a call for business that could help to supply ventilators or ventilator components [1].

Large manufacturers including Vauxhall and Airbus are apparently planning to produce parts [2].

[1]: https://ktn-uk.co.uk/news/call-for-businesses-to-help-make-n...

[2]: https://www.theguardian.com/business/2020/mar/17/uk-manufact...

Is negative pressure ventilation any use in treating Covid-19? Iron lungs are easier to build than positive pressure ventilators. I imagine many HN readers could build something like a Both respirator[0] in their garage over a weekend. Using negative pressure ventilation might be a better option than trying to attach multiple patients to a positive pressure ventilator.

[0] https://en.wikipedia.org/wiki/Both_respirator

Theoretically yes, in fact it may actually be better. We have largely abandoned negative pressure ventilatory support for a number of practical reasons. Not least is that once you have intubated a patient, they are less contagious!

No, in the case of ARDS, you need positive pressure (especially "back pressure" during exhalation) in order to keep the alveoli open.

https://en.m.wikipedia.org/wiki/Positive_end-expiratory_pres...

We are talking about negative pressure mechanical ventilation. Positive end expiratory pressure is just one way of splinting open alveoli. Maintaining recruitment and V/Q matching in ARDS can be achieved in multiple ways, including negative pressure mechanical ventilation.

Interesting, I'd be curious to know more. My understanding of NPV is that it's primarily useful in cases when the lungs are generally "functional" and some other issue is preventing adequate ventilation.

Anyway, the ventilator hardware is relatively easy to make, a gas pump, reduction and humidifier, plus a few hoses. Literally your granddad's CPAP sleep apnea machine is (almost?) good enough, if it has tuned oxygen intake. I would wager intubating actually makes most problems worse in case of damaged lungs, but with low odds only.

The real problem will be getting actual oxygen (concentrators are not free) and people to tune the system.

Is that what these are?

https://www.youtube.com/watch?v=SVodALR3Zoo

No negative pressure ventilators are iron lung type devices. [0] What's in that video look like just oxygen hoods which surround the head in very high oxygen air.

[0] https://en.wikipedia.org/wiki/Iron_lung

It's both high concentration, and high pressure.

Ah yeah totally missed they were pressurized and inflated.

It could be but we're even further behind being able to support people on negative pressure than we are on ventilators. The biggest issue is the neck gasket, they have to seal well enough to provide the negative pressure without being super tight while conforming to the geometry of people's necks. It's already a big problem for the small number of people left on iron lungs.

https://www.wired.co.uk/article/iron-lung-maker-community

I wouldn't expect this to work: the problem with covid isn't that the patient's muscles are unable to handle the breathing but that the usable lung capacity is too low, right?

But these are definitely worth looking into at least a little, since they're so much easier to make than a modern ICU ventilator.

There are lots of problems with this, but I think it is possibly a better move than some of the home-built ventilators you see floating around.

I’m biased though: I’ve designed a 3D printed improvement on this idea that potentially allows you to ventilate multiple patients with different pressures: https://www.prusaprinters.org/prints/25808-3d-printed-circui...

I was thinking as I read the article that there was a next step innovation in the wings to vary the treatment by patient.

Fellow MD trying to help with engineered solutions.

Perhaps check this out as well; someone used a common valve from a hardware store to titrate pressures up and down: https://www.youtube.com/watch?v=eSVbwWANqRI&feature=youtu.be.

I've been thinking about how we might increase ventilation to one part of the circuit if the pCO2 drops too badly--any thoughts there?

Thank you for pointing this out! I’m trying work out how to get in touch with this guy, unfortunately he has turned off all comments.

I’m not sure I understand your question: do you mean if the one patient is getting hyperventilated? My suggestion is to set the pressure settings to ventilate the poorly compliant compliant lung, then use the flow restrictor to compensate on the more compliant lung.

I thought I remembered reading somewhere recently that 2:1 is already in use in some cases (maybe in Italy?), but I can't find a source.

Is there increased risk of ventilator failure with this approach? That seems like it could be an additional terrible factor to weigh, because parts have become so scarce.

The article makes it sound like the ventilators have a wide enough range of operation to accommodate. It may not work for the tail end (set of 4 people each with large lung capacity), but could work for many.

The 2:1 setup was used to save lives after a mass shootings in Las Vegas a few years ago. They paired patiets of similar size, put them on the same ventilator and double the flow rate.

It was mentioned in a blog post by an ER physician linked from hn back then.

The article for the interested. It's a tough but good read.

https://epmonthly.com/article/not-heroes-wear-capes-one-las-...

I spoke with a father (a pulmonary and critical care doctor) about this.

Based on the specs, he estimates that a single ventilator could support up to 4 patients [0].

The bigger issue is the control system. Ideally, a ventilator will allow the patient to decide when to breath, and provide assistance; only forcing a breath when the patient fails to breath at all. WIth multiple patients, this is impossible, and you are forced to use continuous mandatory ventilation mode, where the ventilator cycles air pressure at a constant pattern regardless of what the patient is doing. Modern ventilators do not even support such a mode; although it can be emulated by programming the ventilator such that it would never detect a breath.

Another issue is doctor error. When programming a ventilator you can either program it in terms of air-flow or pressure. With multiple patients, programming in terms of air-flow is almost certainly wrong, and would cause a change in condition of one patient to negatively effect the treatment of all attached patients. This problem goes away with pressure based controls. However, if you have doctors who are used to using flow based controls, and are overworked, while using a novel treatment method, I would expect to see accidents where they either continue to use flow-based controls, or do switch to pressure based but are less effective at it due to it being yet another change from their normal practice.

Another downside is that all patients attached to the same ventilator need the same settings. You could potentially mitigate this cheaply by using analog pressure step-downs on the valves, but this just compounds the above problems, and introduces even more room untested elements to the equation.

[0] The exact number depends on how much airflow you want to provide. Apparently, in cases such as this, you actually want to provide relatively little airflow to avoid further damaging the lungs by over-inflating them.

I encourage anyone wanting to help to try and finds ways of manufacturing the essentials of PPE that we need to limit spread, as that will have a much bigger impact. Every hospital and clinic in my area is running out of masks (both N95 and surgical), gowns, plastic goggles and starting to get into issues with disinfectants. Having double ventilator use is a nightmare scenario for various reasons. There are much better proactive things you can make and donate, but please reach out to your local clinic or hospital and ask first if they have guidelines or material information on what they need before assuming.

It would be good if they found a way to decontaminate the masks so they could be reused a finite number of times, instead of treated as totally disposable. As far as what I've read, there are many things that can kill the virus: hydrogen peroxide, alcohol, uv sanitizing lights, heat, time... Seems like you could come up with a cheap and simple routine that would be 99+% effective, at least for coronavirus specifically. Sure this isn't optimal, but a lot of things aren't optimal these days.

Something that occurred to me was a "hot closet" of some kind that was held at a temperature high enough to accelerate deactivation of the virus without damaging the masks. Perhaps around 130 F would be the right temperature.

Advantage would be that it would not require liquids of any kind and not be labor intensive.

We are reusing all N95 masks where I work because there aren’t enough. Each employee gets one. To try and protect the N95 and make it reusable without risk (they are not designed to be reusable) we are wearing a standard surgical mask over it, and this standard mask gets thrown away with each use. Nobody here is going to be able to independently make N95 masks but the simple masks can be made of well filtering thick materials. Plastic goggle/face shields can also be made from clear plastic.

That's been my question as well. Why doesn't spraying N95 masks with isopropyl alcohol work?

1. Spray mask with alcohol.

2. Place in the sun or under UV light.

3. Wait as many hours/days as possible before reuse.

Seems better than re-using a highly contaminated mask day after day. I'm not an expert so I could easily be wrong though.

I think the issue (although I don't know for sure tbh) is that there is potential damage to the fibers which make it such a good filter. For example, our infection control policy is that we are supposed to throw away the N95 if it gets visibly soiled or liquid gets on it per our infection control. I would imagine damage from UV light could also cause issues.

The reality is that we all need to have our own individual PAPR systems but we simply don't have the supplies and probably won't for weeks or months so we need to do the best we can with what we have and try to minimize the amount of healthcare workers who get sick and spread it or get taken out of rotation and place a bigger burden on the system.

All of those break down the mask fibers or screw up the electrostatic qualities used to grab particles. There have been studies on it, but there's not really an ideal way that doesn't damage the filtering capacity over time.

From what I understand the virus breaks down with time at room temperature anyway, so you could possibly just get away with tossing them in a box for 10 days (or whatever time gets you 99+% virus breakdown). That would have minimal negative effect on the filter material and elastic straps.

Alternatively you could bake some masks, high enough temperature will kill the virus. Or sanitize it with chlorine gas.

I don't understand why so much of the talk is about ventilators. It seems like a massive increase in production of masks, gowns, and goggles would be easier to accomplish in the short term and also essential.

People keep talking about ventilators. The only study I've seen w.r.t. ventilator success for COVID-19 treatment showed something like 3% survival for those mechanically ventilated.

Do we have more data showing they even move the needle?

I've seen figures showing a 50% success rate. I assume that the success rate is very low with much older patients because intubation itself causes a lot of damage.

This isn't right--almost all with beds in the ICU right now are mechanically ventilated; >50% will survive.

Wuhan study of COVID showed 31/32 died: https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

non-COVID mortality is typically a coin-toss: https://www.google.com/search?q=mortality+rate+ventilators

The lancet article is what I've seen.

I think early on, it was assumed ARDS was the worst outcome; your lungs stopped functioning and ventilation would tide you over.

But the more we dig in, there are multiple systems failing and ARDS is just one of many destructive processes going on.

This is one of the really important data points to work out. If almost everyone ventilated will die... it makes no sense for hospitals to extensively treat this way. Give people palliative care. It directs resources away from other, more productive efforts... for example ... running clinical trails on potential treatments to PREVENT ARDS/sepsis.

We should be building palliative care centres across the country, not pop-up hospitals.

Pay everyone who contracts Coronavirus in the next 4 months and is refused ICU care, $100,000. If they die, the amount is divided between their surviving immediate family members or previously registered carer.

The current panic seems to be driven by the guilt of not being able to treat everyone. This payment should alleviate that guilt and allow us to continue with life.

This will become standard in about a month I bet

I hope not, but if this can save a few extra lives that would probably be better than any hack I ever pulled off.

There is quite some discussion of it here

https://emcrit.org/pulmcrit/split-ventilators/

It has certain disadvantages (like not being able to trigger a breath on yiur own)

The video's here, in Italy, show the ventilators used with a bag over the patient's head to create a bubble of positive pressure (and quarantine off their head).

So presumably in a scenario like this it's less of a problem about 'triggering own breath'.

https://news.sky.com/story/coronavirus-they-call-it-the-apoc...

This sounds like a real-life kind of trolley problem ( https://en.wikipedia.org/wiki/Trolley_problem ).

Makes me wonder if there's now a black market and/or hoarding for CPAP and BiPAP machines. Not really a substitute for a ventilator, but better than nothing if the hospital has nothing for you.

You do need oxygen though, moistened and well tuned percentage to pressure.

Would require a modification to the mask or hose for most of these machines. (One way valve from O2 source at least.)

The virus doubles in less than a week, so this hack (which is being used extensively in Italy from my understanding) can only by you so much time to stop its spread with mitigation measures.

Depends on whether you flatten out the growth rate. It won't/can't keep growing like that when everyone is sheltering in place.

Seems likely. Italy is currently seeing a 13% increase per day while the US is now very close to a 50% increase per day. There are news reports showing beaches and bars in the US are still fully packed. It probably relates the US culture of disregarding expert advice and doing the opposite to "own the scientists"

It's not just the US. This happened across countries in Europe as well; Italy had it happen, Germany had "Coronavirus Parties", even. It happens because some people are idiots, and others aren't quite aware of how serious the situation is.

Once reality sets in, only the absolute idiots that don't care for being socially ostracized (or in some cases even legal consequences) will continue that behaviour. And luckily those are normally a minority.

The US federal government isn't actually doing much at the top level. Individual states are shutting down at variable times and rates. The beaches and bars are mostly in these slow-moving states.

That is because that is how our system of executive administration is designed. It is a federal system with the vast, vast majority of police powers (https://en.wikipedia.org/wiki/Police_power_(United_States_co... residing in the state, not federal authorities.

In ordinary times, yes, the US is a federal system of states with some level of individual state rights. But state power has somewhat eroded over time; federal supremacy is a thing; and there is plenty of precedent for the Fed stepping in during emergencies and war. (And war is a relevant point of comparison because even if this thing goes as well as possible at this point, it's likely going to kill more Americans than any foreign war and probably more than the civil war.)

No, the reason the top level federal government isn't doing much is because Trump is an incompetent idiot who doesn't have a second brain cell to rub against the first. The federal government has the funds and the coordinating agencies (FEMA, CDC, military and national guard) and could be buying masks, ventilators, tests; solving distribution problems; coordinating with states on social distancing and even lockdown/shelter-in-place policy. They did nothing during the early weeks when they knew it was a coming problem and it is not clear how much Pence is doing now.

As a matter of law the federal government controls the international borders and inter-state boarders. It is up to the state governments to limit movement within their borders. https://www.cdc.gov/quarantine/aboutlawsregulationsquarantin...

As it so happens, President trump has been limiting international travel starting all the way back in January.

Why do you think the federal government isn't "doing much" (https://www.usa.gov/coronavirus)?

And what exactly would you have it do that you don't think it is doing?

People stop very fast when people they know start to get sick and die.

When that happens, it's too late. Between the incubation period and the time to death it's about three weeks. At a 20% increase per day that means that even if you stop going out at that moment deaths will be multiplied by 46. If the rate is 30%, the multiplier is 247.

Not quite that bad.

Current measured growth rates are closer to 15% per day (5 day doubling time). And people's behavior changes not when people die, but when people get sick. Which happens (depending on your sensitivity) only 1-2 weeks after exposure.

But the basic principle still applies. We are trying to buy as much time as we can to ramp up emergency provisions. And are trying to avoid overwhelming emergency rooms. By the time people's behavior modifies through direct experience, it is too late.

Making this concrete I live in Orange County, CA. Population, 3.3 million. Hospital beds, 6600 (source https://www.hasc.org/orange-county). I don't know how many ICU beds, but https://www.accjournal.org/journal/view.php?number=630 suggests it likely is about 6% of the total. So about 400ish.

Now walk that backwards. 400 people in ICU beds probably means 4000 people with symptoms means less than 0.1% of the population with COVID. Except that it is worse than that. We have those beds for normal stuff that goes wrong. They aren't actually empty now.

Long story short, we start piling up excess dead bodies due to lack of capacity long before most of us personally know anyone who actually shows symptoms.

> Current measured growth rates are closer to 15% per day (5 day doubling time)

Citation needed. In the US, via Wikipedia:

https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_t...

   2020-03-17  5656 infected  96 dead
   2020-03-19 11980 infected 172 dead

That's doubling time of 2 days, not 5. When was it 5 days the last time? If that 2 days continues, in two weeks: 1.5 million infected, 22000 dead. Also, the data across the world show only: the typical doubling time once it really starts going is 3 days, never 5, at least without the beneficial contribution of lockdowns:

Italy dead:

   2020-03-16 1809
   2020-03-19 3405

It's 3 days doubling time there, and they started to quarantine municipalities since February 22, and locked down the whole country on March 10.

https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_I...

Netherlands dead:

   2020-03-16  24
   2020-03-19  76

Doubling time faster than 3 days there. Not much of measures.

https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_t...

So "the risky hack" this article is about buys one not more than 3 days under the circumstances.

Speed of deaths is a good indicator because the number of those who die and those who need an intensive care unit are very close.

A lot of countries aren't able to test as much as it would be needed, so the number of "verified cases" which have less serious symptoms tends to be lower than the actual numbers. But those who die and could have been exposed to the virus and have matching symptoms are more consistently tested.

Main point: the US data can't be considered in vacuum, we know much more than US was able to test due to their botched procedures. But across the world, it's nowhere 5 days, as soon as the number of dead is more than a single digit.

At least some of that growth in the US is probably due to increased testing availability, not infection rate, so I'd suspect "actual" numbers of infected in the US on 3/17 were higher than the data showed. But that's dealing with lots of unknowns.

Epidemiological estimates and projections seem to be based on the 5 day estimate. See https://www.hpnonline.com/infection-prevention/screening-sur... for an example. I am honestly not sure of all the lines of evidence leading to that estimate, but I've seen it used a number of times.

Measuring what is going on by confirmed cases measures ramping out of testing more than the actual growth of the virus. Death figures are likely to be more accurate. But note that we expect it to take 3 weeks before quarantines show up in fatality figures. (A week for exposed to get sick, 2 more weeks before they die.) Therefore Italy shouldn't yet see the benefits of quarantines.

What you cite is from: https://www.imperial.ac.uk/media/imperial-college/medicine/s...

topic of which isn't the evaluation of the recorded growth across the world, but to show that lax measures are problematic even using the slower growth rates.

They specifically write just:

"Infection was assumed to be seeded in each country at an exponentially growing rate (with a doubling time of 5 days) from early January 2020, with the rate of seeding being calibrated to give local epidemics which reproduced the observed cumulative number of deaths in GB or the US seen by 14th March 2020."

That's what they use in their model to demonstrate the point.

They never claim it's accurate or quote any sources for that number, because they just use that very "optimistic" value for the demonstration purposes: to show that even with that number, it's not reasonable not to implement serious measures. That's how mathematical proofs are constructed: you construct the lowest bound which doesn't have to be accurate, just to be obviously lower than the actual numbers, and show that even then some assumption doesn't hold.

I'm claiming here that that is not a "current measured rate."

> But note that we expect it to take 3 weeks before quarantines show up in fatality figures.

That's why I've stated about Italy: "they started to quarantine municipalities since February 22." It's not that they let it waiting for "herd immunity" like UK or NL. It was less than 4 weeks ago.

    2020-02-22     2 dead
    2020-03-19  3405 dead

with 3 days doubling time they would have today 2048 dead. It doesn't appear to be possible to be slower than 3 days. With 5 days doubling time they would have now just 128 dead, with 4 days doubling time 256 dead. It's that easy to calculate.

That's the Italian "current measured rate" for a month now.

The growth rate is different in different countries. The USA is currently on a 35% slope. http://nrg.cs.ucl.ac.uk/mjh/covid19/

That is growth rate as measured by confirmed cases. However given various restrictions on availability of testing, confirmed cases and real cases are likely to tell very different stories. Given that most countries refuse to test, refuse to test, hit an "oh shit moment" and start ramping up, the confirmed rate that your link uses measures testing more than actual infection rates.

References such as https://www.imperial.ac.uk/media/imperial-college/medicine/s... have used a doubling time of about 5 days. As https://www.statnews.com/2020/03/10/simple-math-alarming-ans... points out, studies of what happened in Wuhan suggest a real doubling time of about 6 days.

There are admittedly a lot of question marks about everyone's numbers.

New York's growth rate is going to look terrifyingly high as testing capability ramps up significantly.

It is ramping up significantly, with a corresponding growth rate of confirmed cases. 4 days ago it was approaching 1000. It will probably be 10,000 by tomorrow.

There has been a steady drumbeat of warnings to expect that spike, but unfortunately the statistical nuances of epidemiology will be lost on many.

The people who are going to die are already in very poor health. The median age of deaths in Italy is 80 from yesterday's data. [1]

Previously it has been communicated that 99% of deaths are to people with existing health problems.

https://www.reuters.com/article/us-health-coronavirus-italy-...

There are two people in my life I expect to die of the virus: my sister who is in her late 20s, with a lifetime history of Anorexia/Bulimia, who is currently in stage 5 kidney failure. Secondly my Aunt, a lifetime smoker, who currently has terminal lung cancer.

Both of these people, speaking personally, are going to die sometime this year. Will their deaths be accounted against the Coronavirus death toll or to their underlying conditions?

Is there any point to shutting down everything for 18+ months so that they can live another few months, doing so under lockdown conditions and general panic, with nobody able to visit them? And at the end of it all, many of the people who care for them will be unemployed.

I have said this before I will say it again: people in 2020 are visual learners. There needs to be a boat load of citizen journalists posting videos with dying people and sick people on IG/Twitter/TikTok/Tinder/etc for behavior to change.

Hash tagging #coronavirus #wfh on a photo of a table full of food and 65" TV with Netflix makes it sound like a party.

They kept giving reasons why this might not work...

  * not tested in humans
  * cross infection potential
  * different sized people mess it up

... but I see no reason why any of these things would stop me from using this in the real world. If things are bad enough that we need to do this, then we should be able to find relatively similar sized people. Cross contamination is not a concern when someone is dying here and now and likely has the same disease as the guy next to him who is also dying. Priority 1 is save them. Make their next of kin sign a waver or something, but save them. Lastly, who cares if it hasn't been "tested"? It was used in the real world, in a real life and death scenario, and it worked. I'd absolutely take my chances with it given that the failed option is to pull people off and set it back to single person mode. At least try.

Lastly, I would imagine that some common pressure regulation values could be used to compensate for different sized people.

> Cross contamination is not a concern when someone is dying here and now and likely has the same disease as the guy next to him who is also dying

If COVID evolves into multiple strains, then there is a real risk of cross-infection that would make the immune system forced to work harder? Moreover, a lot of the pneumonia deaths are not due to covid itself but rather due to opportunistic infections (often bacterial) that end up causing the pneumonia that causes death. Letting two COVID patients share a ventilator could mean that now one is exposed to a novel bacteria in the other that causes them to develop pneumonia.

But it doesn't have to be covid patients. There will still be people who need a ventilator but aren't part of the epidemic, freeing up ventilators for covid patients.

As an example, my aunt just recently had a heart attack about two weeks before this covid stuff and had to be put on a ventilator. While in the ICU she developed an infection from a rare fungal disease that had been in her lungs for a while but suddenly had the opportunity to grow and cause respiratory distress. A lot of people have strange microbes in them that are being held at bay by the immune system. When all of a sudden you expose an already immuno-distressed person to someone else's novel microbes, you risk opportunistic infections, even in non-covid patients.

I'm sure they can figure out how to re-use ventilators, but there probably needs to be some kind of assurance so that things can't cross.

Based on data from China, 97% of the people who need ventilators will die anyway:

https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

The Ventilator just keeps them alive for a few days, but there are other bodily systems failing and causing death.

It's not exactly "different sized people mess it up". It's not just different lung capacities, but different lung compliance-- which also changes over the course of disease.

Most simple pressure regulators will not fare well in the environment, either, because of the bidirectional flow, etc.

The "Y" hack definitely has use, but finding matches and keeping patients matched definitely means we will only be able to use it sparingly.

The flow direction issue is partly addressed by the unidirectional valves in many ventilators/anaesthesia machines. The bigger issue is staffing expertise, I fear.

True. Unfortunately, there may be a wide amount of practical experience shortly.

Coronavirus destroys lung tissue and weakens the immune system. Then bacteria move in. It's the bacteria that cause the pneumonia. Different people will likely have different bacteria in their lungs.

That is incorrect for most cases. Viral pneumonia is by far the primary cause of lung obstruction in covid-19 patients, and just about all of them are on antibiotics from the start so bacterial pneumonia will have a hard time establishing itself.

This is another article seems to be written by someone who has deep knowledge about this topic.

https://emcrit.org/pulmcrit/split-ventilators/

Continuous mandatory ventilation (CMV) is required, however it is necessary to accept permissive hypercapnia.

If some untested and unapproved method like this is used and something goes wrong, I would image that being a huge liability problem.

Good on them for trying to save human lives, but our legal system does not always reward the ethical behavior.

I would hope that our legal systems account for the context in which these actions occur. It feels like a larger version of the Good Samaritan Act. They might do harm but they're doing nothing else but trying to save lives. This isn't carelessness or greed driving this behaviour.

Our laws are not a suicide pact and sometimes they must be broken.

I believe the government is working to reduce liability risk so that more n95 masks can be used in medical environments. Perhaps that can be done for this too.

Governments are already loosening licensing requirements to practice medicine. If this approach has support among the relevant healthcare workers and agencies, then we see executive action to allow for such a measure.

These type of "save lives" things tend to have bipartisan support so you can ram through any laws needs fairly fast. Very much doubt any politician will be caught on the wrong side of such a vote

It was my understanding ventilators also do CO2/O2 analysis to understand how to work on the fly, how would that work in this case?

I would assume those numbers would be meaningless. This is a hack, so the main goal would be to simply keep as many people alive as possible.

I've seen it discussed by intensivists on Twitter in January, that they've used it during 2009 pandemic

Here's a tweet saying they're already doing it now: https://twitter.com/PeterAttiaMD/status/1240293938684018688

That's terrifyingly soon

I hope the legal framework does not lead to people like her getting sued over their attempts to help

i dont know if im stoked or depressed that "risky hack" manifested in my mind after reading the title, as it has in irl

if it comes to it, you can probably do three to a ventilator according to some people in the industry i have spoken with

Despite the title, the article talks about hooking four patients up to one ventilator.

Middle-out! How could I have not seen this...

There are some odd quotes and grammatical mistakes in this article. For example: “You wouldn’t want to put a patient with severe bronchospasm [sudden contractions of bronchial muscles in the lungs] with a patient that does not have bronchospasm because that would.” Likewise, one of the cited authors’ names, Babcock, is misspelled in the piece as Babcok.

I’m not qualified to assess whether this risk is worth it but I am surprised that Vice’s editing is so shoddy. It certainly doesn’t engender faith in the veracity/accuracy of their reporting.

> one of the cited authors’ names, Babcock, is misspelled in the piece as Babcok.

And also "Babock".

Vice’s articles are always full of typos. I suspect they don’t have a copy editor.

It’s unfortunate, because their reporting seems to be quite good.

It looks like they have since fixed the errors you mentioned, yet they still misspell the author’s name as “Babock.”

Also a spelling error here: “Let’s say 10 people are dying in front of you and you have one ventialtor. That’s a tough call.

guess they prioritize shipping and just debug in production!

Maybe typos are good for SEO ? People often make mistakes or typos while searching.

Is it because they do sick ass shit or because they're rad as hell?

https://www.youtube.com/watch?v=FWVNDfDSE44

https://www.youtube.com/watch?v=EWbgKCENqn0

Terrible choice of words for the headline. Adding two negative-persuasion terms (risky hack) to bias the reader. What we need right now is encouragement of innovation in all sectors, not some inflammatory headline scaring people. Vice is not helping our combined effort.

"Risky hack" is not something I want to apply during a sanitary emergency

This may sound hyperbolic, but world wars are full of risky hacks, when things are dire. It's good to have them on napkins in back pockets, just in case.

it's all about tradeoffs

of course you don't want to

but in italy, fatalities increased because there aren't enough ventilators.

US is days away from that point

so if it's a matter of no ventilator or a dirty ventilator, most people will take the dirty vent.

after all: the sanitary crisis is for Coronavirus, and you already have it.

I was wondering about he infamous Liston's most famous case

https://en.wikipedia.org/wiki/Robert_Liston#Liston's_most_fa...

What's the alternaitive, just not even trying to help half of the people you could theoretically save?

First aid is a list of risky hacks that are used only during emergencies.

Cross infection?

F! This solution might be worse than the disease.

More than one person needs the only ventilator. Could you explain how they are worse of sharing a ventilator than being dead?

There is a material risk that you are more likely to lose both than just one. I'm sure that having patients share a ventilator increases the risk of death over each having their own. How big that increase is determines whether or not the strategy is valuable.

This is ridiculous!

Hacks are ok with web and app deployments where you are able to patch and fix to your heart's content and the damage is not life threatening.

I have worked with the medical industry, the amount of formal validation and verification that goes through on software is insane compared to what we have in the "move fast and break things" world.

Even if it is "temporary" and "desperate" I would stay away from this mentality as much as humanly possible.

In Northern Italy patients are being turned down on triage because there is not enough treatment capacity. They go home and many of them die.

Just like you would use a sweaty t-shirt over an open wound in a life or death situation if there is no certified sterile bandage at hand. The calculus is different.

On more than one occasion I have "broken the rules" or Macgyvered my way out of a life-threatening situation (for my patients), either with equipment or drugs. This is a crisis. Our systems aren't working fast enough to cope.

This is completely the wrong attitude.

Different circumstances with different levels of risk, require the ability to adapt.

Nobody is suggesting 'sharing ventilators' would be normal practice because in normal circumstances we want to make sure that equipment is 99.999% reliable.

But as you imply, this requires extensive testing and regulation. Within these regulations are also significant safety margins that can be exploited if conditions change. If we can multiply the usage and maintain 99.99% reliability, then this is probably a risk worth taking.

Also - if you've worked in the medical industry, you know how vastly overpriced and bureaucratized everything is.

The situation of 'not enough ventilators' is literally happening right in front of us, and it is causing death.

The risk tolerance for utilizing the gear in such a manner is such that it may very well be possible to create better outcomes.

The individuals involved are medical practitioners who are well versed in the equipment, procedures, and inherent moral dilemmas, they're not fools.

This is exactly the kind of procedural innovation required in times of crises - hopefully, a few doctors and especially the Engineers from the manufacturer can be involved. The people who built the gear may be able to give a much better articulation of the actual risks involved, and they may even be able to mitigate, for example 'the risk will be power consumption' or 'the risk will be this specific valve which could wear and break' thereby implying the 'new operational procedure' would involve daily checking of said valve etc..

The world is facing crises we absolutely must be adaptive while trying to quantify risk and outcomes.

>Also - if you've worked in the medical industry, you know how vastly overpriced and bureaucratized everything is.

Quality guy here,though not in medical devices... Yet. Still trying to get up to speed on all the regulations; but I know enough to be able to vouch for some of the bureaucracy around the industry.

The risks in medicine being what they are, when launching into any novel space, there is simply no substitute for A) data and B) audit trail.

Your data varies from lot numbers of source material from suppliers (contamination happens), batch numbers of parts (and revision numbers of the process involved in making that batch) from manufacturers, to serial numbers matched up to individual patients in order to be able to implement some form of high-level statistical process control, and rapid intervention when things go wrong in order to figure out why, what you can do about it, and who else may be at risk. No one wants to be the one told "whoops, someone goofed, and that thing we put you on is trying to kill you," anymore than anyone in the chain from treatment inception, to installation wants to hear that they missed something, and even worse, get caught not knowing what to do about it.

That means paperwork, signalling mechanisms, and procedures involved with marshalling whatever response is to follow, which is not at all a trivial process to orchestrate, and while all of us wish there wasn't so much bullshit, there are plenty of examples where "falling asleep on the job" has led to catastrophic outcomes.

I can't necessarily say I that justifies the overriding though. The markups are ridiculous, but without access to the books, I can't really discount it either.

So if you end up in a situation where a doctor is deciding whether to put multiple people on a ventilator, is the idea that they would certainly pick you?

You don't seem to be reacting to the situations that the idea addresses, situations where there is an immediate shortage of ventilators.

Such a foolish statement, you clearly don't understand the number of lives lost due to ventilator shortages right now or you'd delete your comment in embarrassment. Doctors should be using absolutely any method available to them to maximize lives saved. You don't need to "have worked with the medical industry" to understand this perspective.

How many lives have been lost due to turning up at a hospital and not being able to find a ventilator so far? Do you have a precise stat?

As of about 48 hours ago Lombardy's hospitals were not turning anyone away:

https://www.cnbc.com/2020/03/19/italys-death-rate-reaches-re...

Medical facilities in Lombardy will “soon” be unable to help new coronavirus cases, regional Gov. Attilio Fontana said Wednesday, as he urged everyone to stay at home.

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