So, what's the gripe? You draw a gun on a cop, expect to get shot. Sounds like blue-suicide to me.
More seriously, that's a tricky issue for a patrol officer which smacks of a no-win situation. I came across one drunk I knew who drew a knife when awoken by paramedics. I knew the drunk (a regular of mine) and explained to the paramedics that it was a natural reflex of streetpeople to behave as he did and had he been cognizant of who they were, would not have done so. That was only a knife though. Trouble with a gun is if you stand back and use the PA system on the car (assuming you have one at your disposal), and she awakens and is hostile, you've lost the element of surprise. You get into a shootout anyway (and what of collateral damage?). If she isn't hostile, you can extract her from the auto using the felony car stop techniques. Either way, it's a tough one for a patrol officer. I know, call the Sergeant or Lieutenant and let them resolve it. After all, that's why they're paid the Big Bucks.