My initial knee jerk when I started watching was to check for pulse, then the classic start the breathing, stop the bleeding, check for wounds, treat for shock. He obviously started breathing again after a moment. Tourniquets would've been a given. Any discoloration would've been a red flag for internal bleeding. Thats my extent of interpretation and abilities. Collapsed lungs etc are beyond my abilities. However I am confident I could perform a field expedient tracheotomy.