Hi,
I managed to draw blood from another player, and create a bloogbag IV. Did not test the bloodtype (I think I read somewhere that EVERYONE has O+ bloodtype at the moment). I let another player administer the bloodbag IV but nothing changed. The pale/toned down colors I saw in-game did not change. I can not be 100% sure that the other player administered the IV, I did see him equip it and do some kind of animation. He came across as a friendly person, willing to give the bloodbag thing a try.
Get a bloodbag IV prepared, get damaged, have someone administer the IV and see what happens.
I managed to make 4 good blood bag IV's and give them to a friend. He saw absolutely zero change in saturation (screen color) after all 4 bags. Both of us saw the text message saying the blood bag was successful. On a side note, we had another blood bag earlier on and gave it to someone and they passed out after a few seconds. As we didn't test the blood type, I'm almost positive that he passed out because it wasn't compatible with his blood so that part of the blood transfusion mechanic seems to be working.