So its a bit for a story, sorry. My barred rock was attacked by a dog on the 23rd. This was my first chicken injury so forgive my inexperience. I inspected her tail because she was missing most of her tail feathers and found that it had split open. I treated that with an antibiotic powder and isolated her with fresh food and water. I was hoping she would bounce back but after a day and a half an still limping around, i inspected more thoroughly and found a bigger wound on her left side behind her leg about the size of a 50 cent piece and smelling of necrotic tissue. For the next two days i cleaned it three times a day with dilute h2o2 and packing it with triple antibiotic ointment (vet's orders). She improved rapidly. After the two days i started cleaning with dilute betadine and still packing with triple antibiotic. It was that evening i found another wound between her wings on her back, i cleaned it with betadine and packed it. the next day i notice the skin around the wound on her back wasnt attached for quite a way around the opening so i started squirting the betadine in it and squeezing the ointment as far back as i could. She has been improving daily, eating more and more, and walking very well. Today,during her outdoor time, she decided to take a dust bath and get sand in everything. I took this as a very good sign because she was bathing herself again. It came time for her to come inside and get cleaned up so i brought her in and washed out her wounds under luke warm water in my sink, she seemed to relax a bunch under the running water. She was dirty enough that i decided to use the h2o2 again to make sure her wounds were clean and bubble out any sand i couldnt get. So i started washing her back and cleaning under the skin, she started to keep her head low and breathing hard. I stopped on her back and moved to her side. While cleaning her side i noticed anywhere i touched on her leg or left front side felt spongy and i could feel the bubbles from the h2o2 popping. i stopped cleaning and tried to push out all the foam gently. It was around now that she seemed to have a stroke, writhing and contorting in my hands. I seem to remember her screaming the whole time but i cant be sure. She died in my hands. After i calmed down and confirmed she had passed, i had to know why, so i cut open her side where all the foam was but everything looked well. I did find a small abscess above her left leg and aside from a rather large pocket where i felt all the foam, everything was as i expected. What did i do wrong? Did i kill the chicken i spent so much time caring for? Please help me understand where i went wrong.