Marianne, it is not a matter of "we". It is the companies that manufacture these things. It is intellectual sloppiness to ask why aren't "we" doing that. Of course if you want to start up a company to build them, you are welcome to do so.
Because we would still be short of humans to manage the extra vents. ICU nurses, Respiratory therapists and intensivists are vital to keeping vented patients alive. Having more vents only solves part of the problem.
