Why a vent?
That's a good question. They knock us out pretty deep and the Rectus Abdominus is spread apart,,,(open) The diaphragm is opened I believe and that's the muscle that makes us breath,,,, so maybe we need help. I bet it's worse for those of us who have apnea. I was with three patients this past year who woke up in ICU for breathing problems but they knew ahead of the SX that it could happen so they were prepared for it.
If you find out why exactly let me know.
kp
For any "major" surgery -- during surgery -- you are "intubated" and hooked to a machine that "breathes" for you -- a.k.a "vent"; the anesthesia medications they give you are pretty "heavy" and you would otherwise not breathe on your own. So, unless they use a spinal or "conscious sedation" (mostly for very minor cases), one would be on a "vent" during surgery. Most just don't think of it in those terms. Hope that helps.