With this cold spell of weather we often think of old and infirm family members being affected by hypothermia but surprisingly your dog (and to a degree your cat) could also be at risk. Here we look at what it takes for your pet to succumb to the condition, how to spot the symptoms, how it can be treated and what the probable prognosis could be.

Causes

Hypothermia most commonly occurs in cold temperatures, but it can also be associated with a rapid loss of body heat, which could occur even on a warm, sunny day. Whilst newborns may suffer hypothermia in normal environmental temperatures; smaller breeds and very young or older animals are most at risk. General health or more specifically poor health can also increase the risk.

Hypothermia is characterised by abnormally low body temperature and has three phases: mild, moderate, and severe. Mild hypothermia in pets is classified as a body temperature of 90 – 99°F (or 32 – 35°C); moderate hypothermia at 82 – 90°F (28 – 32°C); and severe hypothermia is any temperature less than 82°F (28°C). Hypothermia in your pet occurs when they can no longer maintain normal body temperature, and the central nervous system is affected. It may also affect heart and blood flow (cardiovascular), breathing (respiratory), and the immune system.  An irregular heartbeat, trouble breathing, and impaired consciousness to the point of coma may also result.

Symptoms

The symptoms brought on by hypothermia do vary. Mild hypothermia typically causes a lack of mental alertness plus is evident through weakness and shivering. Moderate hypothermia reveals characteristics such as muscle stiffness, low blood pressure, a stupor-like state, plus shallow or slow breathing. When escalated up to severe hypothermia, characteristics typically include fixed and dilated pupils, inaudible heartbeat, difficulty breathing, and even a coma.

Diagnosis

If hypothermia is suspected, your dog’s body temperature will be measured with a thermometer or, in severe cases, with a rectal or esophageal probe. Irregularities in breathing and heartbeat will also be checked and if equipment is available, an electrocardiogram (ECG) will be done to record the electrical activity of the heart as this can determine your pet’s cardiovascular status. Urine and blood tests are typically done during the initial diagnosis as this can identify alternative causes for the symptoms, for lower than normal body temperature and unresponsiveness. These tests may reveal low blood sugar (hypoglycemia), metabolic disorders, primary heart (cardiac) disease, or anesthetics or sedatives in your dog’s system.

Treatment

If hypothermia is diagnosed, movement should be minimised to prevent further heat loss which will also help prevent the symptoms escalating. Slow and gentle heat is then administered, however, at the start of the process an initial drop in body temperature can be expected, as contact is made between warmer ‘core’ blood and the cold body surface.

With mild hypothermia treatment may be passive, simply using thermal insulation and blankets to prevent further heat loss leaving the patient’s own body to generate and raise the overall body temperature. With moderate hypothermia active external re-warming like the use of external heat sources, such as radiant heat or heating pads, is common. These can be applied to the torso to warm the ‘core’ but a protective layer should be placed between the skin and the heat source to avoid burns. For severe hypothermia, invasive core warming will be necessary, such as the administration of warm water enemas and warm intravenous (IV) fluids. Breathing aids may also be used to provide additional support. Close monitoring of body temperature, blood pressure, and heartbeat should be observed when any treatment is administered and It is also important to check for secondary symptoms like frostbite.

Prevention and outcome

Unwell or newborn animals with low blood sugar (hypoglycemia) are more at risk for hypothermia even in normal environments while low body fat is another contributing factor. Hypothermia can be prevented by avoiding prolonged exposure to cold temperatures and by ensuring that your pet’s have a warm and dry environment when they return from a walk or period outside. Whilst most animals should recover from hypothermia if identified and treated properly some long-term care may be necessary.

If you suspect that your pet is exhibiting signs of hypothermia or indeed any other illness, you can ask us for some advice but you should consult your vet at the earliest opportunity.