She had a hysterectomy with an epidural. She specifically said she had an epidural. The concern was likely that airway management was going to be a huge concern if she was under general anesthetic. An epidural is very effective for pain managment... but it does nothing to decrease a patient's level of awareness. You would NOT want a patient completely alert and oriented while a surgeon is cutting them open and giving instructions to the surgical team. Again, Amber complains about panic attacks over SHOES, she would lose her fucking shit if she heard her surgeon saying things like "More suction.... I need this cauterized; there's too much blood here", while feeling weird sensations in her abdomen. Versed takes the edge off. It calms the patient, disorients them, and lets the pain meds do their thing. If she just had Versed, she'd be in the O.R. screaming like she was being murdered - because that's exactly what it would have felt like to her. She never said she had Versed. It's just something I speculated, based on what I just mentioned.
The scenario I mentioned about Versed with the possibility of no pain meds was cardioversion. In an emergency setting, you likely don't have pain meds strong enough to block out the sensation that must feel like sending a lightning bolt through their heart. And you don't often have time to get to a cardiac ward where you have access to all of the specialists who can make that happen. You're in a regular office, or bedroom, or even the floor of some grimy GAS STATION with this sweaty gray dude that looks like 10lbs of shit in a 5 lb bag.
Hopefully, one of the medics on scene (or en route) is level 3, or advanced care, or EMT P, or whatever they're called in that particular service, because if not, it's not going to be pretty. This ends up being the most likely scenario:
No ACLS available... FUCK! Run like snot to the hospital and hope he doesn't code.
Fucker goes into V-fib en route; VSA.
DEFIBRILATION - one shock administered
The defib assesses patient - Asystole ("flatline")
Fuck, time to give epi - oh, no-can-do because of that pesky lack of ACLS
Run like snot to the hospital while doing CPR and hope the doctor's can bring him back and it's not too late.
The scenario with Versed isn't much prettier. Patient is warned of procedue. ACLS certified medic follows the protocol for Versed, and maybe morphine/fentanyl? (I'm old as fuck and don't know if it's still used in an emerg pre hospital setting - I just remember that the amounts that Paramedics were authorized to give were weak as FUCK and barely took the edge off - TMI, but the one time I got one of those emerg doses of morphine, it did NOTHING for the pain). And then the medics on scene grit their teeth, put on their stone-cold no emotions facial expression, and wait to see the nightmare, because half-dead dude WILL SCREAM like he's had a knife plunged into his heart. But it's pain for a second one or two times, then it's over - and from his perspective, it never happened because he has no memory of that pain. And, he's ALIVE when he gets to the hospital. So yeah, all in all, good outcome.
I can't speak of any other conditions for Versed, because honestly I don't know.