Since a lot of people seem to have missed the last half I'll start...others who saw the end please add in...
FIrst point...we are left in suspense at the end, so don't expect closure!
At the end McD. is still operating on Bailey's husband who is going from bad to worse apparently. Bailey has been told by Addison that her husband had an accident. Only part of the hospital needs to be evacuated (not the OB section, only surgery) so Bailey is still in labor. She gets upset and says she's not having the baby til her husband is there (just before that she said she was 9cm dilated, so baby obviously should be arriving shortly) and starts to cry, I can't do it alone (I think she meant raise the child, not just deliver it) and George is there. We didn't really see him respond to her statement other than the look on his face.
Meanwhile in the other OR the paramedic (Christina RIcci) and the anesthesiologist are the only ones left in the room with the bazooka guy. The bomb squad guy (Kyle Chandler) and the doctors are outside looking at the Xrays and agreeing they can't tell what would happen if she let go, other than that the guy would bleed out. The anesthesiologist, who is just squeezing a bag of air into the guy's lungs because having oxygen would be too dangerous, starts talking about how the bomb guys say when a bomb goes off you turn into pink mist and scaring the paramedic. Then he suddenly shows her how to work the air squeezing bag and leaves, saying, I've got 2 kids, and she is all alone in the room, with one hand in his chest and the other working the air bag. Christina and Mer realize this and go in to help her but the paramedic starts to freak out and suddenly pulls her hand out after a struggle with Mer. Dr. Burke and the bomb squad head have come in and have been telling her not to move her hand. Everyone hits the floor except Mer who puts her hand in the guy's chest to control the bleeder. In the last scene McD. is still operating and learns that the girl with the bomb is now Meredith.
Meanwhile on the side, for light relief, George and Izzie have been talking about how they are not do-ers like Meredith and Izzie and that they need to take what they want from life. Izzie tracks down Alex, drags him into a supply closet (and see all the above comments), tells him she wants sex and to take off his pants, which he does. One hopes she is at least on the pill because I didn't see anyone carrying a condom in that situation.
Otherwise just some scenes with the wife of the bazooka victim yelling at his friend who helped make it, realizing she's likely a widow, the bomb guys talking about how unstable the bazooka shell will be given the amateur construction, etc. What did I miss?
ETA You beat me to it,
Nilesgirl!