The following is basically a copy of a post I made on another forum -

It may well come to this - home brew ventilators -

https://www.inquirer.com/health/coro...omo=newsletter

I am mechanically inclined enough to do minor wood and metal projects around the house. I am of the opinion that the virus is going to overwhelm the health care system in a very short amount of time. There will be many more people needing ventilators than there is a supply. That being the case, 'You're on your own" takes on a whole new meaning.

From the above link, a mechanical ventilator needs to supply about 400 milliliters — a little more than a soda can’s worth - of air. More may damage the lungs.

See -

https://www.youtube.com/watch?v=4J0d59dd-qM

paying particular attention to the doctor's comments on getting 'tired out.' This is at about 22 minutes in, and describes the muscular effort required to breath. It's like curling a barbell a thousand times - the abdominal muscles just can't do it.

Is there a way to home produce something that would force air into the lungs mechanically? The hard parts, as I see it are -

- One-way valves to direct air into a pump, then close

- some kind of a bladder to collect air and pump it with the assistance of a lever

Any ideas? We may be needing them.

Thats what this whole quarantine thing seems to be about, making sure enough medicos are there to monitor ventilators ...

Ventilator#Open-source_ventilator

Open-source_ventilator

8127281/Engineers-develop-share-open-source-designs-DIY-ventilators
...
Julian Botta, a third year resident in emergency medicine at Johns Hopkins, created a Google Doc listing some of the basic specifications for a ventilator and how a do-it-yourself version might be assembled.
The idea came to him after he saw several similar projects spread across Github but was concerned that many of the designs were closer to CPAP (continuous positive airway pressure) machines than ventilators, according to a report in Vice.
...
Ventilators are complicated devices that require skillful technicians to use properly, and they're also subject to FDA approvals which mean most home projects are likely to unusable for most hospitals.

...
Gui Cavalcanti, an engineer based in San Francisco, decided to refocus his own DIY ventilator Facebook group called 'Open Source Ventilator Project' after consulting with medical professionals.
'The said, Listen, ventilators are not the issue,' he said. 'The issue is literally everything else.'
He decided to rename the project 'Open Source COVID 10 Medical Supplies' and instead focus on other resources like masks and gloves.
...


whats-plan-c-for-covid-19

Open Source Ventilators
Many groups have sprung up online, using Facebook and/or Slack, including:
Open Source COVID-19 Medical Supplies Facebook Group
Open Source Ventilators (OSV) Ireland
Helpful Engineering Web site
Project Open Air Web Site
TOM Global
1 Million Ventilators

https://www.facebook.com/groups/opensourcecovid19medicalsupplies/
http://opensourceventilator.ie/
http://www.helpfulengineering.org/
https://www.projectopenair.org/
https://tomglobal.org/community?id=5e73198894711e10b13ebe3b
https://helpwithcovid.com/projects/13

Here's our (UK) requirements for an emergency ventilator

https://assets.publishing.service.gov.uk...MVS001_v3.1.pdf

For a one-way valve, look at a fireplace bellows. A small electric motor attached to one handle with a belt driven cam to set the RPM's and a filter and you have the basics of a ventilator.

professionals, would something like this work?

flow chart in order of components

air source... small home air compressor

breathing control... normally closed air solenoid, and adjustable timer to control rate of valve opening

pressure regulator... LP style regulator to drop supply air pressure to usable air pressure

filter media...P95 filter material to filter out any oil to prevent mechanical pneumonia

clear plastic tubing, connect to nasal pharangeal airway for non ER intubation

I believe they also enrich the air with oxygen.

Measuring the effective operation of the lungs requires measuring peripheral blood oxygenation. Pulse oximeters, which shine red light throught the finger or earlobe, measure the saturation of red blood cells by color. I bought one at walgreens for about $40. This will let me know if I, or the 88 and 98 year old in my care, are decompensating. Lets me give the 911 operator a better idea of what's going on.

Course of illness of first 12 patients with Covid-19 :
None required a vent, apparently. Caveat:if any of the information in the article is confusing to you, you probably shouldn't be playing around with a ventilator.

Successful use of a ventilator requires aintubation with a cuffed endotracheal tube. Anesthesiologists created field expedient et tubes with condoms. If you do not have intubation supplies and skills, see Caveat.

Successful use of a ventilator requires
-a large supply of medical grade oxygen
-access to anesthesia, sedation, and analgesic drugs
-IV access and fluids
-assessment skills sufficient to diagnose misplaced et tube, subcutaneous emphysema, pneumothorax, pneumo-mediastinum, esophogeal intubation.
-arterial blood gas monitoring capability to detect alkalosis/acidosis, pH and HCO3 levels.

If you don't have these things, see caveat. I worked with patients on vents in ICU's and ers for a long time. It's complicated. Moreover, vents don't save everybody. If the lung tissue is thoroughly compromised,ventlators don't work. The alternative is ECMO Which is so difficult to use that no one is even talking about it.

Most of the patients who heve respiratory distress need supplemental oxygen: it might be productive to look into builing a home oxygen concentrator

If you want to go to the moon, you don't start by building a rocket ship: you start by studying physics.

IMHO/YMMV

My apologies, all.
If building a diy ventilator helps you cope with this hideous situation, by all means do so.
It beats the hell out of doing nothing.
The US Gummint tried to do something similar. https://www.nytimes.com/2020/03/29/business/coronavirus-us-ventilator-shortage.html

They failed but not for practical reasons.

But do be careful out there.

Here's a list

https://docs.google.com/spreadsheets/d/e...dslCXdM/pubhtml

Would these help? (Obviously, one would require a truck-load of them...)

https://www.rei.com/product/144881/boost-oxygen-canister-10-liters?CAWELAID

I saw in the news today that hospitals had to put patients on oxygen therapy and hoped for the best because they did not have enough ventilators.

What you have there wouldn't even work as oxygen therapy unless a person stood there regularly replacing canisters. Also, how do you adjust that thing? How much oxygen is the patient getting?

Starting at eight-years-old, I had to help my grandmother, who was on oxygen therapy, which is how I learned about oxygen systems.

Jeanette Isabelle

I know some of our army were specifically trained for driving tanker lorries, specifically for delivering oxygen to hospitals.

And hospitals are normally plumbed for delivering oxygen, similar to how water is distributed thoughout.

Trying to get my head around the thinking here. Are we planning to build a diy ventilator and set up an icu unit at home, or are we planning to take our ventilator to the hospital and offer it for use in their icu?

Manually operated man-portable ventilator: $20

bag-valve-mask

You would know better than me, but I have the idea that these are not practical for more than very short term use.

Never used one for more than four hours:a neonate with continuous seizure, too tiny for any of the vents at the community hospital. Waiting for the pediatric medeva to arrive. There's no theoretical limit on use except manpower. And, in truth, manpower is the major limiting factor we will face. We are building out beds in NYC pretty efficiently, but not filling those beds with covid patients. Staffing is at least part of the reason.

from the spreadsheet supplied by Ren... this design from Israel looks like it might have promise... Nursemike?

https://members.smoove.io//view.ashx?message=h44803226O122324982O219654O122394144&r=1009

It's a bvm squeezer. Clever solution to the bellows/compressor issues, but limited control over oxygen flow, room air or 100%, and limited control over inspiratory pressure and volume. Both are critical values for anything but short term ventilation. Injured lungs are stiff lungs, and can rupture from excessive pressure or volume. Room air is probably insufficient to maintain saturation, and 100% oxygen can cause damage in several different ways.
Crowd sourcing is a powerful tool for mobilizing innovative solutions to complex problems. It is also how the Royal Navy wound up with a research vessel named Boaty Mcboatface.

I rather like Boaty McBoatface!