I had a one lung / gut shot this year. I basically just washed out the cavity with water really well. I also had to give the deer a "greyhound" cut. I basically cut out the exit wound area from the hams to the ribs, you know its right when your deer looks like a greyhound instead of a deer. Really all you need to is let it hang for a day and then smell the inside of the cavity if anything starts smelling nasty start cutting out that area.