Check out the other posts on this subject in the "injuries" forum. If you have chlorhexidine, clean it with that. Or whatever antiseptic you can find. Iodine works. 1/2 strength hydrogen peroxide (dilute with saline if you have it, or boiled, lukewarm water.) Flush it with the spray from a syringe if you have one, or cover the chick's face so you don't get it in the eyes and nostrils. Point the chick's beak up to the ceiling so the antiseptic flows down the BACK of he head to the floor. After it is well flushed out, use an antibiotic ointment, and keep the chick warm and dry, making sure it drinks and eats. Keep it away from flies to prevent maggot infestation, and hopefully it will heal in on it's own. Try not to touch the wound too much with your fingers, to avoid introducing bacteria when you are checking the looks of it.