Hypothermia

Hypothermia is a condition where the body temperature of homoethermic (warm blooded) animals falls bellow normal. The center of thermoregulation, which is situated in the brain (Hypothalamus), controls the body temperature, keeping it within the normal range utilizing several mechanisms. Animals conserve heat by behavioral responses as well as physiologic responses, such as peripheral vasoconstriction to reduce heat loss and erecting the hair to trap air and create a layer of insulation, shivering and increased activity.

Thermoregulation is more likely to fail in neonates, geriatric animals, sick/debilitated animals, Hypothyroidism or anesthetized animals and after prolonged exposure to cold.

Animals with mild hypothermia (90-99° F) exhibit mental depression, lethargy, weakness and shivering. Moderate hypothermia (82-90° F) is characterized by muscle stiffness, slow heart and respiration rate, low blood pressure and unconsciousness. In severe hypothermia (< 82° F) Heart sounds cannot be heard and breathing is difficult where the animal is comatose with dilated, unresponsive pupils.

Treatment is done in a hospital setting and includes immediate life support measures ensuring breathing, oxygenation and circulation and limiting movement of the patient. Gradual body warming may be done using blankets, warm pads as well as warm water gastric and peritoneal lavage, warm water enemas, warm IV fluid administration, and airway warming (using warmed air).

On cold days in wintertime, outdoor activities should be minimized and pets should be closely supervised as hypothermia can occur quickly. In case of moderate to severe hypothermia, pets should be wrapped with a blanket, placed on a stable surfaced and rushed to the closest veterinary hospital.