If it can save the life of or comfort a wounded soldier on the battlefield, I say shoot a pig, stick a goat, and burn whatever you need.
If you studied hard, passed your tests, care for what you are trained to do, and are determined to give your brothers the best care they could possibly get under the circumstances then you will do fine.
I am a NYS Paramedic with 13 years of experience. I know that does not compare to being a combat medic but it does compare to being confident in your training. Your training will not fail you. Sure, working on live flesh is great for getting the "feel" of starting lines, intubating, putting in a chest tube, etc. However, I do know there are a lot of training aids out there that do feel like the real thing.
What is tough is when you have to intubate a person. In class you trained with a mannequin on a table in a well lit room or if you passed a tube in the Operating Room during your clinical rotations you were lucky. When do you get to do it for the first time in a real situation? YOU GUESSED IT...in a truck that is upside down in a 15' trench at 0145hrs on a man with half of his face missing while the truck is trickling gas into said ditch and a trooper is lighting a road flare 40' away to divert traffic! Thats WHERE!
The first time I did a chest decompression was in a flattened house and an active, on the ground tornado about 1/2 mile over my left shoulder. I peed a little but my training kicked in and I got the job done.
Train and talk to those with experience, that will give you what you need better than a pig with a gut wound.
"Who are the militia? Are they not ourselves. Congress have no power to disarm the militia. Their swords, and every other terrible implement of the soldier, are the birth-right of an American...(T)he unlimited power of the sword is not in the hands of either the federal or state governments, but, where I trust in God it will ever remain, in the hands of the people." (Tench Coxe, Freeman's Journal, 20 Feb 1778)