I was on a plane that had a medical evacuation once. A passenger who had eye surgery that morning suddenly started bleeding from his eye about halfway through a flight from LA (Orange County, IIRC) to SFO. I forget the type of plane, but it was an almost fully loaded 3+3, 120-150 passengers.
They announced the procedures before we landed and EVERYONE complied. They started de-boarding from the front. Everyone was to remain seated until the flight attendants got to their row. Then, the people in that row were allowed to stand up and retrieve their luggage from the overhead bins. (This was allowed because the plane itself and the passengers still aboard weren't in any danger.) Most of the luggage was near the passenger who owned it, but some had to go forward or back quite a way to get to their luggage. This was no problem because the aisle was empty.
They were waiting for a wheelchair to carry the injured passenger off the plane. When it arrived at the door to the plane, they halted the process, the wheelchair and an EMT came down the aisle and got the man into the chair, and then they took him off the plane.
When he was off, they did NOT just resume the normal free-for-all, but continued with the systematic, one-row-at-a-time procedure. It took about two minutes, including the time to evacuate the injured passenger, to get EVERYONE off the plane! With all their luggage! Once the passengers understood what they where expected to do, it was really quick.
The one thing I don't understand is why they don't ALWAYS do this. Is is really any more work for the flight attendants to walk down the aisle controlling the flow instead of standing at the door saying "Guh-buy Guh-buy" until their vocal cords expire? If everyone was familiar with the procedure, evacuation in a life-threatening emergency such as a fire would be MUCH quicker. Just do the same thing, but leave your luggage.
Oh, before anyone asks, the man did have explicit permission from his surgeon to fly that afternoon. But clearly it was a wrong decision.
