
Project Open Air - mhb
https://www.projectopenair.org/
======
mike_d
"Open source ventilators" are a really really bad idea.

Patients on ventilators need to be intubated first, which involves using a
specialized tool to insert a tube down past the vocal cords and inflating a
balloon that seals the airway. You can kill a person before you've even turned
on your nifty machine.

Once you have a patient tubed, you have full control of their respiration. If
your calculations are wrong you either over inflate the lung and they
literally burst, or you under oxygenate and the patient dies of oxygen
deprivation.

I know engineers look at something like a ventilator and go "you don't have
enough machines? I can make machines!" This is very admirable and I appreciate
the desire to help, but I can't stress enough how dangerous this is.

Edit to add: This study showed that trained paramedics were only successful in
tracheal intubation 52% of the time. You have a 0% chance of doing this at
home. [https://www.jwatch.org/na47414/2018/09/07/maybe-
paramedics-s...](https://www.jwatch.org/na47414/2018/09/07/maybe-paramedics-
should-not-perform-endotracheal)

~~~
jariel
This is not a fair assessment and I think it sidesteps the point.

"This is very admirable and I appreciate the desire to help, but I can't
stress enough how dangerous this is."

Indicating that 'medical equipment requires specialization' is not a special
insight that most people are going to miss.

Assuming that the product will be designed by those who lack credibility or
that such equipment might not be of sufficient quality of design,
construction, or that it may be misused is unwarranted.

'Open source' encryption and other systems are behind the entire world's
financial systems, it has integrity partly because it's 'open source'. It's
not designed by fools, and just because jokers and everyone else can 'fork and
do something' doesn't mean it will be implemented anywhere that matters.
Obviously regulations, security, risk etc. play a role 'where it matters'.

Any kind of medical equipment development is going to require some kind of
oversight, regulatory approvals, and special manufacture, but this is all
feasible within the concept of 'open source'. There are plenty of highly
credible and knowledgeable people, possibly even those who have worked on
'closed source' ventilators can possibly contribute.

Sheppard through some kind of regulatory process, manufacturing setup, and
possibly deployment and training, it's not infeasible at all that something
like this could help.

Even the availability of high-quality, unlicensed equipment designs, with
parts pre-designed for manufacture and ready to be made by qualified entities
... could feasibly make all the difference in the world.

For example, once a design is complete and approved, the medical wing of a
poor country, or possibly an NGO could facilitate the actual manufacture and
distribution to medical staff in various places.

There are massive margins (bordering on criminal) in medical equipment and
supplies these days, hospital beds now cost more than automobiles (!), it's
high time there was an open approach to such issues.

I can absolutely see medical researchers and PhD's at universities, teaming
with Engineers, MDs, and manufacture/supply chain specialists to produce this
kind of stuff.

Obviously there's a limit to complexity here, but I hope they figure out not
only ventilators, by any number of other kinds of gear.

Though odds are it will fail, it's not a bad idea, it's a great idea.

~~~
UncleMeat
> Assuming that the product will be designed by those who lack credibility or
> that such equipment might not be of sufficient quality of design,
> construction, or that it may be misused is unwarranted.

Given the number of software engineers who have written detailed and strongly
opinionated analyses of the situation rather than relying on expert
opinions... I'm not so sure we can assume that this project is operated by
experts.

------
ggreer
Neat idea, though I think it will be quite some time before it produces
something that people can build or use.

Another option might be to figure out ways to adapt existing ventilators to be
used by multiple patients. If you find 4 patients with similar tidal volumes
and body size, you can grab some Y tubing, attach them to the same ventilator,
then set it to 4x the tidal volume and breathe for all of them.

This has been studied before[1] and was done in at least one mass casualty
event[2]. The main disadvantage is the risk of spreading germs (though the air
return hose is separate from the incoming hose, so that shouldn't be too much
of a problem) and the fact that patients sharing a ventilator require more
careful monitoring of blood gasses.[3]

I doubt patient outcomes will be as good as having one ventilator per patient,
but if it can increase our capacity by 4x overnight it seems worth pursuing.

1\.
[https://www.ncbi.nlm.nih.gov/m/pubmed/16885402/](https://www.ncbi.nlm.nih.gov/m/pubmed/16885402/)

2\. [https://epmonthly.com/article/not-heroes-wear-capes-one-
las-...](https://epmonthly.com/article/not-heroes-wear-capes-one-las-vegas-ed-
saved-hundreds-lives-worst-mass-shooting-u-s-history/)

3\.
[https://www.resuscitationjournal.com/article/S0300-9572(08)0...](https://www.resuscitationjournal.com/article/S0300-9572\(08\)00542-X/fulltext)

~~~
tgsovlerkhgsel
My understanding is that what a ventilator does is basically:

\- supply pressurized air to patient \- turn off the pressure, open exhalation
valve and let patient exhale

Given that every hospital I've seen has compressed air outlets, wouldn't it be
possible to get acceptable results with a pressure regulator and a timed set
of valves? Or is the pressure required to fill a patient's lungs so high that
the volume must be controlled?

~~~
cameldrv
My layman's understanding is that ventilation is a fairly complex art/science,
and that modern ventilators have multiple modes that are effectively different
control laws.

I think that the pressure required to fill a patient's lungs is quite
different in a COVID patient than a normal patient, because the disease has
caused huge flow restriction in the lungs. I think that generally you want to
control flow rate, because you need to get a particular respiration rate, and
the lungs can hold a certain amount of air. You then use whatever pressure
gets that respiration rate.

If the pressure or flow rate is too high, I think that that can cause lung
damage, so one option is to increase the oxygen concentration in the air
you're delivering. My understanding is that the downside is that although this
will lead to more oxygenation, it doesn't help any with removing CO2. If you
reach this limit, the only option is then ECMO.

~~~
loeg
> My understanding is that the downside is that although this will lead to
> more oxygenation, it doesn't help any with removing CO2.

If your input is O2 (or O2+N, no CO2) and you run part of the pressurization
cycle with the exhalation valve open, won't you displace at least some CO2
(not in tissue, just in the lung cavity)?

------
Gatsky
This is madness. You can’t scale up ICU based ventilatory support to keep up
with a pandemic.

All resources should be going towards infection control measures, a quick and
highly scalable diagnostic test, and antiviral therapy. In that order.

~~~
klipt
Exactly, you can't fix an exponential problem with a linear solution. If the
caseload doubles every two days, shutting down cities two days earlier is
better than _doubling the number of ventilators_ (because even with
ventilators, more infected means more deaths).

Note that Wuhan shut down when they saw 400 new cases in a day, and their
hospitals were still overwhelmed. The USA is over 400 new cases daily already.
That's comparing a country to a huge city, but in exponential terms that only
buys you days at most.

See [https://medium.com/@tomaspueyo/coronavirus-act-today-or-
peop...](https://medium.com/@tomaspueyo/coronavirus-act-today-or-people-will-
die-f4d3d9cd99ca)

~~~
Gatsky
Also people don't seem to realise, a patient on a ventilator is extremely
unwell. They are the most unwell people in the entire hospital. They have 24
hour 1 on 1 nursing, constant invasive monitoring of vital signs, blood tests,
X-rays, CT scans, antibiotics. They are managed by a team of extremely well
trained and highly experienced senior medical professionals. And this goes on
for a week or more. Then they leave ICU and proceed to be the most unwell
people in the hospital except for those still in ICU. They might have various
other complications, and need several more weeks to recover, often needing
inpatient rehabilitation.

This does not scale.

------
rkagerer
No real information. Marketingy-pictures. This seems like total fluff? I feel
like the other HN post about DIY ventilators is a lot more interesting.

~~~
evolve2k
The point is the gathering of a network of people to tackle open engineering
needs.

------
Animats
Or you could just order one on Alibaba.[1]

More likely to work than something from a website-first operation with no
product and no manufacturing capability.

Now that the coronavirus epidemic is winding down in China, demand for those
units is probably down in China, so getting delivery is probably not too
difficult.

[1]
[https://www.alibaba.com/trade/search?fsb=y&IndexArea=product...](https://www.alibaba.com/trade/search?fsb=y&IndexArea=product_en&CatId=100009290&SearchText=medical+ventilator)

------
Peradine
ICU ventilators are surprisingly complicated machines, we've just brought some
HAMILTON-C6 machines at work if you want an idea of the top of the line

I would consider the following a bare-minimum feature set for a COVID patient
ventilator, any less and it would do more harm than good:

\- cycle between an inspiratory and expiratory phase

\- during the inspiratory phase, deliver an adjustable volume of gas (in the
region of 6 ml per kg of patient's body weight) using as little pressure as
possible, with an adjustable upper limit of pressure (in the region of 30
cmH2O)

\- during the expiratory phase provide an adjustable pressure against
exhalation (in the region of 0-30 cmH2O)

\- allow blending of air and oxygen to deliver an adjustable inspired oxygen
fraction

\- allow the timing of the inspiratory and expiratory phases to be
independently varied, thereby allowing the respiratory rate and the ratio of
inspiration to expiration time to be controlled. Permit respiratory rates in
the range of 8-60 breaths per minute

\- measure and display the pressures and volumes within the respiratory system

\- allow adjustable alarm-limits for pressures and volumes, and provide clear
audible and visual alarms if these values are exceeded

For added patient safety and benefit, the following would be helpful

\- measure inspired and expired oxygen and carbon dioxide content, and display
both on a continuous waveform graph

\- allow the patient to initiate the inspiratory phase by sensing patient
inspiratory effort and providing pressure support for inhalation; ie sense
when the patient inhales and deliver 10-15 cmH2O pressure for 0.5 seconds to
augment inhalation

------
alphachloride
So somebody built a website, a google spreadsheet, a github repo with a
readme, and a slack channel. I am skeptical. This seems like a promotion for
the company hosting the project.

------
VectorLock
I keep wondering if existing CPAP/BiPAP machines can be software adapted to
serviceable ventilators. Some BiPAP machines are identical to units produced
for NIV.

~~~
davak
Yes. Very easily.

~~~
VectorLock
Has anybody done it? Is there any effort to collect them incase ventilators
get scarce, I wonder?

------
ColonelSanders
An anonymous spinup website. For some reason, some feel the urgency to put
affairs into order on when its trending. Not before that, though?

Wouldn't hospitals, WHO, UN, whoever be able to come together with their
capital and just buy out a medical company?

Wouldn't this have to also get past regulations? I'm not too sure if I want a
kickstarter for medical equipment. I'd love to see medicines and medical
equipment made open and maintainable though!

~~~
Fiveplus
I wouldn't be surprised if this is the reasoning behind Apple and the likes
preventing any new apps with the corona theme into the app store unless they
come grin reputable sources like WHO.

------
wiseleo
All the activity is on slack, so pay no attention to what’s on the site. :)

As to whether people are serious, here’s a document from one of the channels.
[https://docs.google.com/document/d/1RDihfZIOEYs60kPEIVDe7gms...](https://docs.google.com/document/d/1RDihfZIOEYs60kPEIVDe7gmsxdYgUosF9sr45mgFxY8)

------
lazylizard
How about make apps that make contact tracing easier?

~~~
spiorf
That train departed a few weeks ago.

