I fucked up my knee real bad as a teenager doing something stupid and had to get a couple rounds of surgery to get it sorted out. I can’t do general anesthesia because it’ll send me into a depressive episode, so I get epidurals instead. The last surgery I got was when I was maybe 24.
I did the epidural method for that one. From what I remember the anesthesiologist injected some fentanyl derivative directly into my spinal column, and - I basically just fucking spasmed out of pure joy on the gurney. I blurted aw, FUCK YEAH real loud because fentanyl direct to the brain is like Sex With God, and every person in the OR froze for a second, unsure of how to respond.
My point is, this is completely realistic.