Fake blood is available at many costume shops this Halloween season - handy for bandages, makeup for 'patients", etc. It'll be hard to find in another month, so buy now if you need it. About $8 per qt.
Last year I got a couple of "amputated limbs" to use in a field hospital set - put a torn boot on the foot & you'll totally gross out the visitors who don't think you get the details "right". All kinds of scars & wounds available in the makeup section.