Yes. I can't breathe well after I've been given that. Its horrible after.
Try to stay well is all we can do

Make sure they know before you go under so they can compensate for your condition.

It's generally no problem. Make sure the anesthesiologist knows that you have COPD and that you use O2 so he can be prepared. Just about everyone gets O2 during surgery, and for a time after. You'll be no different except that you may keep yours on if you use it 24/7.

Well I had 2 procedures done under anesthesia, I would imagine it would depend on the condition of your lungs, I am a stage 4 and they did two Brohnchioscopes on me so ??

I've had both; twilight for things like colonoscopies and general anesthesia with intubation for other surgeries. No problems with either.