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Pandemic Ventilator Project

panvent.blogspot.com

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Re: Pandemic Ventilator Project

#91

Post by projektfu »

yourapostasy wrote: post #76
projektfu wrote: post #29

I would imagine an epidemic of ventilator associated lung injury if people started rolling out homemade ventilators in quantity.

Please don't take this as a personal address to your specific comment. Yours was simply the last drop of water that tipped the scales in me to comment on an overall trend I'm seeing. What I'm beginning to see in a lot of these types of discussions is those calling for caution/compliance are missing the term "in extremis". I've seen no one is suggesting that these DIY/hacking efforts of all stripes replace the existin…

I think it’s better than the hubristic and idiotic mentality of hackers thinking they can hack the medical field. This ventilator design sucks. It was designed without input from a pulmonologist friend. People are talking about it like it’s a reasonable response to the problem. This madness is worse here than anything.

Re: Pandemic Ventilator Project

#92

Post by gentleman11 »

My parents both have lung conditions. If this were Italy, and they got infected and needed ICU, they would not get treatment at the moment.

What is the most promising home made gear I might be able to scrap together in the worst case scenario?

Re: Pandemic Ventilator Project

#93

Post by Peradine »

I'm an anaesthetics and intensive care trainee, so I know something about ventilation. The reason COVID-19 patients need to get ventilated is due to a failure of oxygenation - the infection causes direct lung injury (ARDS) which impairs oxygen absorption in the lung tissue. Normally we breathe room air, which is 21% oxygen, this drops to around 10% oxygen in the arterial blood due to inefficiencies in the absorption in the lungs. In a normal healthy patient breathing 100% Oxygen, their arterial oxygen content would be around 90%. ARDS significantly impairs oxygen uptake by the lungs, in severe cases patients breathing 100% oxygen may have arterial oxygen concentrations of just 8-10%.

The purpose of ventilation in these severe ARDS patients is to augment oxygenation of the blood, using a combination of techniques including end-expiatory positive pressure and inverse-ratio ventilation, among others, and support the fatiguing respiratory muscles. Because the lungs of COVID-19 patients are already injured by the infection, they are very prone to further ventilator-associated injury. Modern intensive care ventilators have complicated computer-controlled 'modes', which allow precise regulation of ventilatory volumes, pressures, rates, timing, and gas blending. The ARDSnet trials in the early 2000s demonstrated the importance of carefully managed 'lung protective' ventilation, poor quality ventilation is likely to cause further lung injury and make the patient worse, not better. Therefore amateur ventilators are unlikely to be beneficial in COVID-19 unless they can provide similar lung protective ventilation, which would make them quite complicated.

Additionally, ventilation is just one component of the management of sick COVID-19 patients. First you need to pass a breathing tube into their trachea, which is a challenging and risky procedure when performed by a skilled operative in a otherwise well patient, let alone someone on the brink of respiratory failure. Once intubated you will need to keep them deeply sedated, otherwise they will strain against the ventilator and make effective ventilatory care impossible. This requires equipment, drugs, and skilled staff, all of which are going to be in short supply.

Re: Pandemic Ventilator Project

#94

Post by fhsm »

fghorow wrote: post #22
bearsnowstorm wrote: post #7

Earlier quoted context omitted.

- COVID-19 seems to be mainly hypoxic respiratory failure, not hypercapnic respiratory failure - NIV (Non invasive ventilation, CPAP is essentially a form of this) doesn't typically perform well (on a patient outcomes, mortality basis) for pneumonia with hypoxia compared with invasive ventilation. However, this is thought to partly be because NIV delays the decision to proceed with intubation and ventilation. If ther…

Ok, so what is the best way, in your opinion, for a still healthy hacker/maker geek to contribute something (anything?) to helping our local ICUs from being overwhelmed with patients? Edited to add: Spoken as the Dad of a 28 week premie who spent 8 weeks on a ventilator in a NICU.

Develop and validate a low effort contamination free means of n95 reuse than does not increase the burn rate of other difficult to substitute consumables (eg gloves and calstat)

Not sexy. May be irrelevant in 3 weeks at crisis standards. Right now with the supply chain as is and attempting to surge standard of care capacity this is the thing that would be useful. If we cannot manage ppe lack of providers will make lack of anything else moot.

Re: Pandemic Ventilator Project

#95

Post by Scoundreller »

wool_gather wrote: post #72
rectang wrote: post #67

Earlier quoted context omitted.

Anecdotally: My mother is a retired RN with an "inactive" license in Washington state. She does elder care as a side gig for individual clients. She recently had to turn someone down because the patient was intubated; it's not legal for her to care for such a patient. If anything went wrong she could be both at risk of a lawsuit and in trouble with the state for practicing medicine without a license. (She's also in h…

Is it not a "simple" matter of the state waiving license requirements like this? I thought I had heard of this being done already. I.e., either the governor or the legislature says "it's no longer impermissible for RNs with inactive licenses to care for intubated patients". Or even "all inactive licenses shall be considered active on request of the licensee, until DD/MM/YYYY". Fiat, done.

If health care workers start falling ill and going into 14 day quarantines, this will need to happen.

And it would only be a start.

Can also do: if you're currently in a program of studies XYZ and > 75% complete, you can also practice until xx/yy/zzzz and indemnified by government.

Re: Pandemic Ventilator Project

#96

Post by sigmaprimus »

mhb wrote: post #42
sigmaprimus wrote: post #2

Good idea using a large AC blower. I would think a small brand new or very clean wet dry shop, vac using the blower attachment might be even better. It would be noisy but would allow the design to incorporate negative pressure of the vacuum side to assist with exhaling. Maybe the shop vac could be plugged into a speed controller to improve duty cycle and reduce noise but controlling an AC motors speed is quite a bit…

What about using an air compressor? These should still be readily available and is an off-the-shelf air pressure solution. The air couldn't be used directly (oil in it) - there would need to be an isolation bellows or something similar.

Thats a good idea too, and they do make oil-less compressors they are typically smaller but years ago I came across many of these attached to dry sprinkler systems in small parkades.

Re: Pandemic Ventilator Project

#97

Post by solotronics »

Peradine wrote: post #93

I'm an anaesthetics and intensive care trainee, so I know something about ventilation. The reason COVID-19 patients need to get ventilated is due to a failure of oxygenation - the infection causes direct lung injury (ARDS) which impairs oxygen absorption in the lung tissue. Normally we breathe room air, which is 21% oxygen, this drops to around 10% oxygen in the arterial blood due to inefficiencies in the absorption…

As someone with asthma this is terrifying. My worst nightmare is not being able to breathe.

Re: Pandemic Ventilator Project

#98

Post by chimprich »

sowbug wrote: post #66
chimprich wrote: post #51

Earlier quoted context omitted.

Care to explain the downvote? It's a bit depressing trying to do something positive in the current climate.

I didn't downvote, but I can see why others did. If you have an idea to share, share it. Don't make people jump through the hoop of sending email. If you are concerned about others stealing your idea, then your comment is essentially spam, because you're using HN as a recruiting tool to build your team. Only YC companies can do that here. Your motivation might be something other than either of these possibilities. It…

Thanks for the explanation. Makes sense; I've actually posted the idea a few times (including as an Ask HN) and I was getting fatigued. I absolutely have no interest in making money out of this - just potentially saving lives.

Reposted:

Could a voluntary user-tracking app help reduce the R0 level of the COVID-19 virus?

One of the main challenges with this virus is that carriers of the virus become infectious well before they show symptoms. Consequently, they pass on the infection before they can be isolated.

Apps such as Google Maps already track users' movements to a high level of precision. A similar app could be created that tracked users' movements and notified people they had interacted with if they got infected.

It would work like this:

  - Users' movements are tracked
  - Upon developing a fever (etc.) the user notifies the app
  - The app checks their movements during the estimated period they could have been infectious
  - Every other user who was in their presence for X minutes gets notified and requested to isolate themselves
  - Recursively check those users' movements to see if they may have passed on the virus
Disadvantages I can think of off the top of my head:

  - Requires simultaneous voluntary use by a large proportion of a regional population
  - Possibility of false positives by bad actors (would an occasional false positive be so bad)?
I've had this idea checked with a leading epidemiologist, and he was enthusiastic.

I see this same or similar idea has been written up as a paper (which I've just submitted as a separate story): https://www.medrxiv.org/content/10.1101/2020.03.08.20032946v...

Re: Pandemic Ventilator Project

#99

Post by fghorow »

fhsm wrote: post #94
fghorow wrote: post #22

Earlier quoted context omitted.

Ok, so what is the best way, in your opinion, for a still healthy hacker/maker geek to contribute something (anything?) to helping our local ICUs from being overwhelmed with patients? Edited to add: Spoken as the Dad of a 28 week premie who spent 8 weeks on a ventilator in a NICU.

Develop and validate a low effort contamination free means of n95 reuse than does not increase the burn rate of other difficult to substitute consumables (eg gloves and calstat) Not sexy. May be irrelevant in 3 weeks at crisis standards. Right now with the supply chain as is and attempting to surge standard of care capacity this is the thing that would be useful. If we cannot manage ppe lack of providers will make la…

According to this US CDC site, 3M is the sole NIOSH manufacturer of N95 filters:

https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part...

As an Earth scientist, I could imagine a mineral based replacement for the filtering part -- e.g. something like a zeolite -- but the lack of mechanical flexibility and the risk of silicosis are two serious problems with that right off the top of my head.

How about 3D printing of filters? Can N-95 -- 95% of particles greater than 0.3 microns -- be achieved?

Edited to add: It appears somebody is doing this for liquid filtration: https://liquico.com/products/

Re: Pandemic Ventilator Project

#100

Post by 93po »

DataDrivenMD wrote: post #56
wbl wrote: post #38

Earlier quoted context omitted.

Bagging is hard to do for extended periods.

Anesthesiologist here - true, I was a Stanford medical student on an ICU rotation when a Tesla employee crashed his plane into high voltage power lines while attempting to land at San Carlos airport. Electrical power on the peninsula was out for an extended period of time. Battery backups eventually failed, then gas powered generators started failing so everyone with a pair of hands took turns manually ventilating th…

Why is it relevant he was a Tesla employee?
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