<- Navigation document
Have concerns? Please read and contribute to "Red teaming": ~~ AJP (Admin)
Open Source Ventilator
Google drive: Ventilator
Slack channel: #hardware-ventilator
Portugal specific: #hardware-ventilator-portugal
? Upvote this document on Sourceful
For a specific approach based on automating a bag valve mask, head to #hardware-ambu-bag
The list of other ongoing hardware project is here : Hardware Projects (Google drive)
In Italy, each ventilator is like gold. The US, which has an above average medical system, is likely also going to run out of ventilators, let alone countries in the developing world.
The goal of this project is to design an open source, scalable, safe, and easy to use DIY ventilator for use in hospitals.
Have deleted. Use "View" > "Show document outline" (on desktop). Can click links on there to change url to shareable links.
Necessary specs :
Ventilator derived parameter :
The basics of respiratory mechanics: ventilator-derived parameters :
Respiratory support for patients with COVID-19 infection
“Jonathan Chun-Hei Cheung and colleagues do not recommend use of a high-flow nasal cannula or non-invasive ventilation until the patient has viral clearance. Supporting the recommendation of the authors, I would like to add some points in relation to the use of high-flow nasal oxygen therapy and non-invasive ventilation in patients with COVID-19 infection:
First, although exhaled air dispersion during high-flow nasal oxygen therapy and non-invasive ventilation via different interfaces is restricted, provided that there is a good mask interface fitting, not all hospitals around the world have access to such interfaces or enough personal-protective equipment of sufficiently high quality (ie, considered fit-tested particulate respirators, N95 or equivalent, or higher level of protection) for aerosol-generating procedures, and several hospitals do not have a negative pressure isolation room.
Second, the fundamental pathophysiology of severe viral pneumonia is acute respiratory distress syndrome (ARDS). Non-invasive ventilation is not recommended for patients with viral infections complicated by pneumonia because, although non-invasive ventilation temporarily improves oxygenation and reduces the work of breathing in these patients, this method does not necessarily change the natural disease course." (https://www.thelancet.com/.../PIIS2213-2600(20.../fulltext)
That being said, professionals often use NIV to “limp ” a patient along until a ventilator is available.
[FDA] Coronavirus Disease 2019 (COVID-19) Emergency Use Authorizations
This is an authorization for Personal Protective Equipment (PPE), saying that nonstandard N95 masks and the like can be used in medical settings.
Meta: a red team is a team in an organization that goes around trying to show people ways their ideas are flawed, hardening the production process. Ideas that survive the red team have grappled with the ways that they are insufficient, providing a larger context around the idea and allowing for a better picture of the costs/benefits.
Is shortage of ventilators likely to be a limiting step? [b]
Italian doctors referred to them as gold. So yes I think shortage is a problem.[c] China shipped another 1000 to Italy. Why do that if you had enough for your staffing levels? DEFINITELY AN ISSUE< NEED MORE VENTS we are planning to share vents the way we would for a trauma shortage (see articles published around the time of las vegas shooting if you want more details) but may be an issue because of infectious origin rather than trauma
What are the patient need distributions, which cases can we address?
From https://www.ncbi.nlm.nih.gov/books/NBK554776/# - Features, Evaluation and Treatment Coronavirus (COVID-19)
* Mild disease: non-pneumonia and mild pneumonia; this occurred in 81% of cases.
* Severe disease: dyspnea, respiratory frequency ≥ 30/min, blood oxygen saturation (SpO2) ≤ 93%, PaO2/FiO2 ratio [the ratio between the blood pressure of the oxygen (partial pressure of oxygen, PaO2) and the percentage of oxygen supplied (fraction of inspired oxygen, FiO2)] < 300, and/or lung infiltrates > 50% within 24 to 48 hours; this occurred in 14% of cases.
* Critical disease: respiratory failure, septic shock, and/or multiple organ dysfunction (MOD) or failure (MOF); this occurred in 5% of cases.
I would argue that the Severe cases above are the places we can contribute the most. Designing a system for the Mild or Critical cases will have less impact.
Is it wise to spread designs that require skill to make and operate?
Summary[d] - Don't make it easy to be unsafe
If they cause harm they’ll never be used.
Perhaps but there are docs off record saying they would try using them if it was that or patient dying. If they don’t have them they can’t use them.[e][f][g][h]
You're about to say HFOV, CPAP etc. What does that mean?
Look further down the document, you'll find some explanations
Ok but what ventilator? HFOV needs sedation, intubation, bloods, etc Very labour intensive to maintain support for these patients. Staff will be shortage.
Yep. Not going to be an HFOV but could be a NIV like CPAP or BIPAP [i][j]or Cuirass[k]
But NIV, CPAP, BIPAP produce aerosols so they won’t be used in a formal medical setting or where there is a risk to staff and other patients. See interv