Sounds like she was gorked out of her mind. (gorked is a not-so-technical term my dad, a nurse anesthetist, taught me. Means that someone has over-medicated you.)

Basically she's stoned out of her mind...

The orthopedic surgeon did the same thing to my mom when she had a knee replacement. Everytime my mom moaned or something after the surgery, the nurses gave her another shot or a pill...had my mom so gorked that they thought she'd had a stroke. (the MRI showed old damage, probably from her brain concussion 50yrs ago) Once they backed off on the drugs she went back to normal.