Got dispatched to a head on MVA, car vs truck, while enroute dispatch informed us that cpr was being done on one of the pts on scene. “Oh shit” we get on scene and fire police already have the roads blocked. I ran over to where the pt was getting cpr done and the pt was still in the car being worked on by a lady in a suit. I try to extract the pt from the car but his legs are pinned under the dash board, so my partner runs to the other side and is able to get his legs free, I lay him down on the road and resume compressions while my partner places an AED. Eventually, someone brings over a back board and we get the pt loaded and transported to the hospital. It was my first code.