It's tricky. One doesn't know if the person has hepatitis, AIDS or some other disease. Even medical professionals glove-up these days. Most of us don't travel with surgical gloves on hand. Also, there's a limit to what an unlicensed person can do from a medical perspective. Say the shoot is justified and Indiana has a cannot sue law. If a person provides medical treatment and does something injurious, it may give the perp grounds to sue where he could not have otherwise.
In my mind a small trauma kit (with gloves) should be close by any time you have a weapon of any sort. While I am no lawyer, I strong supect that good sumertarian laws would still aply to someone treating an injury even if they where the one to inflict said injury.