Hypothermia and targeted temperature management in cats and dogs

OBJECTIVE: To review current knowledge surrounding the effects, treatment, and prognosis of hypothermia in people, dogs, and cats, as well as the application of therapeutic hypothermia in clinical medicine. ETIOLOGY: Hypothermia may be a primary or secondary condition, and may be due to environmental exposure, illness, medications, anesthesia, or trauma. Hypothermia has been applied therapeutically in human medicine for a variety of conditions, including postcardiac arrest. In veterinary medicine, the technique has been applied in cardiac surgeries requiring bypass and in a patient with intractable seizures. DIAGNOSIS: Hypothermia can be diagnosed based on presenting temperature or clinical signs, and appropriate diagnosis may require nontraditional thermometers. THERAPY: Rewarming is the primary treatment for accidental hypothermia, with intensity ranging from passive surface rewarming to extracorporeal rewarming. The goal is to return the core temperature to a level that restores normal physiologic function of all body processes. Other supportive therapies such as intravenous fluids are typically indicated, and if cardiopulmonary arrest is present, prolonged resuscitation may be required. In cases of secondary hypothermia, reversal of the underlying cause is important. PROGNOSIS: There are few prognostic indicators in human and veterinary patients with hypothermia. Even the most severely affected individuals, including those presenting in cardiopulmonary arrest, have potential for complete recovery with appropriate therapy. Therapeutic hypothermia has been shown to improve outcome in people following cardiac arrest. Further studies are needed to examine this application in veterinary medicine, as well as appropriate therapy and prognosis for cases of spontaneous hypothermia.