Call in advance and see if they have someone who is very good with kids that they can put you in with. DS had blood taken twice. The first time was extremely traumatic because she couldnt find his vein etc and she didnt explain anything very well to either of us. The second time was a different person and place. I thought it would be horrific given what happened the previous time. They deliberately made us wait for this person to do it and she explained it all to him in language he understood, she even asked his permission to do so and it was far less traumatic for us both. If your little person has a special toy or blanket, take it with you. We used ours for distraction as well as comfort afterwards. He also got a treat for being such a brave boy afterwards. Good luck with it!