What prevents this from being an option when the alternative is, I dunno, death?
Is this actually a “ventilator”? Or is it just a mask and it’s the rest of the air delivery system that’s in short supply? Can anyone point to a good basic intro to the “design a ventilator” problem?
A ventilator is a pretty complex, configurable piece of electronics and machinery. It needs to push air in and pull it out at specific volumes and pressures (usually hand-calibrated to the individual patient by a doctor), and do so with a pressure curve that does as little damage to the lungs in the process.
The machines are indeed in short supply (which this doesn't fix), but so are a lot of parts that become contaminated after use on a patient (which this does fix). See also that project going around for 3D-printing replacement valves.
There is alot of selective focus and attention to "ventilators" currently. The danger is people believe that a fuller featured ventilator will save them when in reality (it will in some cases) public health focus should (arguably is) be on everything that can be done to keep COVID patients from being intubated and needing a full featured ventilators.
There is a risk that we run out of ventilators because they are dedicated to long term life support of patients that become dependent on them when they could be providing the short term ventilatory support of patients who will recover enough not need one. This is another scenario given our medical capabilities, well trained healthcare workers, and cultural outlook we are not yet talking about.
In the UK the ethics boards are working on policies for triage
What do you optimise for?
Number of lives saved? Number of Years saved (so better to save someone with a life expectancy of 40 years than 2 people of LE of 5 years each)? Do you remove ventilators from those who it's just delaying the inevitable? How to do you factor in non-covid cases?
Do you take into account how "good" the patient was? Were they self isolating or did they go to a pub lockin? Have they been hoarding toilet paper? Do you save the person who caught it performing CPR? What about the Key Worker who caught it while delivering food to the town? How about the dumbass politician who's encouraging people to ignore the restrictions?
I will say working in a Trauma and ICU rooms, families are generally well aware of the decisions to be made when it is time.
500 people outside need ICU beds, 6 patients have just died, so you have 6 new beds open. Which of the 500 do you treat?
They are assigned a triage score and that score will be updated routinely. As beds open, the people who fit the criteria get the bed. I believe that is fairly standard in a public hospital type setting.
I have only ever worked in public and military icu, wards, er and trauma rooms so I do not know too many details on how that works in practice.
What you refer to as the "hospital's oxygen system" is the oxygen output port on a ventilator. See also this note in the text:
"The prototype as a whole has been tested on one of our colleagues directly inside the Chiari Hospital, connected to the ventilator body, and has proven to be correctly working."
(Note that the mask is general-purpose, so they mention in the video that it can also be attached to a CPAP machine or to a plain old oxygen feed for less severe cases; but people who need a ventilator are still going to need a ventilator with this. They're just going to have a mask available.)