frostbite infection?

Question
Hello,

Almost three weeks ago a newborn puppy was brought to us (umbelical corde included) frozen  and thought to be dead. We live in the arctic and the temperature was around - 40. Long story short, we've been taking care of the pup since, she seemed to be doing quite well. Putting on weight, eating and sleeping well. The tip of her tail which had been blackened from frostbite now seems to be infected, I am quite concerned about this since I've read it could be wet gangrene. We have cleaned the area with boiled salt water (cooled) and applied an antibiotic ointment. She also seems to have a clear runny nose. We are in an isolated community accessible by plane only, no vet in town, and no pet medicine available unless ordered online. When we decided to try and save her, we knew it was a long shot. I would appreciate any advice on how to deal with this considering the fact that we do have much access to basic first aid for pets. She's recovered great so far considering the difficulties she has faced since birth... Thank you for your kind advice.

Answer
The dead part of the tail will most likely shrivel up and fall off to the point where there is some blood supply that is remaining to keep the tissue alive.  Keep doing what you are doing and as long as she is eating and drinking, there is little chance of getting systemically infected.  The tip of the tail could be amputated, but I would not advise that you do this without some help.