not a ventilator...
I am currently at home on a ventilator. It is set to force feed a constant volume of air plus O2. It varies the prellure with a complex algorythm to do this. It does not use more pressure than naecssary to keep my airways open, Without it, my sleep apnea would continue to be killing me. Look up AVAP technology to see how ventilators function in the present — not during the pandemic.