In the last decade, I was put under mildly (?) for an outpatient surgical procedure. I remember trying to tell the doctor that the framerate of my eyes was stuttering (and that I was more observant of such things than some people, due to my career), them telling me to "stop trying to talk" and me trying to say "okay". Next was trying to get oriented in the recovery room to tell the nurse how much pain I was feeling.

In my youth, I was put similarly under for impacted wisdom teeth. I remember becoming aware of the noises and forces on my neck mid-procedure, then opening my eyes and trying to make noises and facial expressions to get their attention. I am not sure how much time passed before I heard one person say, "he's coming out", they paused their work and then it was lights out until recovery again.

In both cases, the anesthesia was explained to me in advance as mild in that my autonomic breathing would still be there, and I could probably respond to them if they talk to me, but I wouldn't remember any of it. Apparently, there is a deeper anesthesia where you are so suppressed that you need more life support and monitoring.