@mattblaze As a volunteer fireman, I had to help perform CPR on a friend who it turned out had an aortic aneurism. He didn't even make it to the hospital even though we were there two minutes after the call came in.
We performed CPR until the ambulance arrived 10 minutes later, but he was declared dead on the floor.
One of the worst days of my 15 year career. It was also another reminder that CPR rarely ends up with a success like it does on TV.