The extent of the injuries varies with the body temperature and duration of hypothermia. Hypothermia can be fatal. Hypothermic animals should be warmed slowly . There are several ways to do this. Do NOT place hot water bottles directly in contact with the animal's body since burns could occur even if the bottles do not seem that hot to you.
Hair dryers can be helpful, especially if the animal is wet as well as hypothermic.
Warm water baths can be used for animals mildly hypothermic who will not have to be transported - taking a wet animal back out into the cold to go to the veterinarian will only make matters worse. While warming the animal, contact your veterinarian who can assess what other treatments may be necessary. Animals who are severely hypothermic may need additional care including intravenous fluids, oxygen, or warm fluids administered into the stomach, colon or abdominal cavity as a way to warm the body core. Animals may experience pain as the tissues warm, and bite at the painful areas. Use care, since animals in pain may inadvertently bite people as well.