HYPOTHERMIA (COLD-INDUCED ILLNESS)
Campaign provided and compiled by Wag'N Pet Emergency Management
The recommended treatment of hypothermia in the field is core re-warming to prevent post-rescue collapse.
Under hypothermia, the body’s heat is concentrated on vital organs, causing a slowdown of: the circulatory system (i.e. heart and veins/arteries); the respiratory system (i.e. lungs), and the nervous system (i.e. nerves and brain). Prolonged hypothermia can lead to permanent organ and/or nervous system damage.
Heat loss or dissipation occurs via four basic forms:
- Evaporation (water)
- Convection (air movement)
- Conduction (contact)
Simply defined, radiation loss involves the transfer of heat as electromagnetic energy (infrared) from the dog to the atmosphere. Radiation is usually the largest type of heat loss, but may be highly variable.
Evaporation is accomplished primarily by panting and salivation, as water is lost from the airway. A situation that results in the animal’s becoming wet will greatly increase the significance of evaporative heat loss.
Convective heat loss is highly variable and depends on wind conditions, speed of travel and respiratory rate (panting), but ordinarily amounts of about 12% in a static condition.
Heat loss through conduction (contact to cold air) is usually relatively small (3%), but will become more significant as ambient temperatures drop and is most critical in cases of water immersion.
Chilling of the entire body from exposure or immersion in extreme cold water results in a decrease in core body temperature and physiological processes that become irreversible when the body core temperature falls below 75° F (24 C).
- Mild hypothermia takes place between 89.6°F to 98.6°F (32° C to 37° C)
- Moderate hypothermia takes place between 82.4°F to 89.6°F (28° C to 32° C)
- Severe hypothermia is below 82.4°F (28° C) can rapidly lead to death through heart failure.
The duration of exposure and the general condition of the animal influences its ability to survive.
Clinical Signs of hypothermia include:
- Mental depression
- Hypo tension,
- Fixed and dilated pupils
- Slow, shallow breathing
- Decreased respiratory rate
- Slow, irregular heartbeat
- Pale, grey or white gums
- Cold gums
- Cold extremities
- Capillary refill over 2 seconds
- Cold breath
- Muscle stiffness
- Decreased level of consciousness
ATTENTION: That animal will need to be transported to the nearest veterinarian immediately!
ATTENTION: The re-warming process is excruciatingly slow – rate of no more than 1° per hour.
ATTENTION: NEVER NEVER EVER use a heating pad! Doing so would cause thermal burn injury!
YOU ARE YOUR PET’S 911 - ACTIONS FOR SURVIVAL
Remain calm! Failure to do so may worsen the animal’s condition as the handler’s excitability will translate in animal getting excited and increase its blood pressure. This is contra-indicated because the crystals that may form in the animal’s bloodstream will travel to vital organs faster as the heart rate is increased, ultimately worsening the condition.
Also remember that you can think more clearly and make decision when you are calm.
Monitor ABCs (Airway, Breathing, Circulation). Administer Rescue Breathing is animal stops breathing on its own or CPR when animal loses pulse (make sure it has no heartbeat before doing so as you can expect a shallow heart rate due to condition)
Wrap the animal in a blanket, and take it indoors or to warmer environment. That does NOT mean applying heat to dog directly using hair dryers, vents, car heat, heat blankets, etc!
Keep the animal OFF the natural earth ground and concrete at all cost as it will absorb heat, furthering injury.
In warmer environment, place multiple blankets between the ground and the animal. Place animal atop. If the animal is too large to pick up and hold easily, lay next to animal (direct contact) to share heat. If animal is small enough to pick up, pick it up and place it against your body under your coat.
Take the animal’s rectal temperature and write it down along with time taken. Seek immediate veterinary help is temperature is below 98°F (36°C). NOTE: Animal’s suffering from hypothermia tend to be lethargic and should not pose the usual resistance to the procedure.
WARNING: DO NOT RUB ANIMAL! VIGOROUSLY OR OTHERWISE! As tissue begins to freeze, ice crystals are formed within the cells. As intracellular fluids freeze, extracellular fluid enters the cell and increase the levels of extracellular salts due to the water transfer. Cells may rupture due to the increased water and/or from tearing by the ice crystals. Do not rub tissue; it causes cell tearing from the ice crystals. This applies to people AND animals.
WARNING: Do NOT put severely hypothermic animal in a shower or bath.
If animal is wet, change the towels (non-heated) frequently.
If possible, have someone else increase room temperature. You may start electric fireplaces and stay near it as it will take some time to warm up and generate heat. Do not get too close. The key is remaining in a warm environment without applying direct heat to animal. Your body generates heat but not extreme enough to pose a threat.
Take temperature every 30 minutes. You should notice no more than ½ a degree increase per half hour.
ATTENTION: DO NOT GIVE ANYTHING TO EAT OR DRINK! The organs are in enough distress and do not need an additional workload. If the animal is demonstrating signs of shock you may apply so regular sugar water, honey or molasses to the animal’s gums by gently rubbing it in.
There is no rule that says you cannot be transporting dog to veterinarian whilst applying these steps. Just remember that the car heat temperature should be on high, and the flow level on no more than medium. Blasting heat will be too much too fast. We recommend making sure the car inside temperature is warm, not hot, when you place animal inside and bring plenty of towels.
The veterinarian will have the monitor the blood glucose, administer heated humidified oxygen, and if the animal is not breathing or severely hypoventilating (shows as: shallow breathing), endotracheal intubation with mechanical ventilation, inject intravenous crystalloid fluids and more.
- Don’t leave animals outside in the cold for a long time and provide access to a DRY and warm shelter
- When out in the cold with your animal make sure you keep a close eye on their behavior
- If the animal gets wet whilst outside, dry it immediately. Do not let it sit in puddles, streams and lakes! Streams are the worst are exposure to fast running water sucks the heat out of most living beings at a much higher rate. No matter where you go, always bring a few towels with you. The more absorbent the better. Leaving the animal wet, even if moving, increases the risk of hypothermia. Synthetic or natural Chamois cloth works best
- Keep wet animals out of wind. Wind factor will increase loss of body heat faster
- If your animal is sensitive to cold weather, limit outdoor exposure to minimum (potty breaks only)
- If you go on longs walks, hiking, snowshoeing, etc with your dog, make sure you have a breed that can withstand the conditions you might face
- If you invest in a dog coat make sure the material you use is waterproof (water resistant is not enough for prolonged exposure). Wind and water proof are best. Neoprene material is generally a safe bet. Then trust but verify throughout the walk to ensure coat does not retain liquid between material and dog’s back
- Do NOT bathe your dog using soap prior (no sooner than 3 days) to prolonged winter outings. No matter what the manufacturer promises, shampoos eradicate some of the dogs’ essential coat oils that serve to protect it from the elements
- Do not let your dog ride in the back of the pick up truck during cold winter months. That gets us back to preventing exposure to wind. Riding in the cabin will keep everybody warm and safe
ADDITIONAL RISK FACTORS INCLUDE:
- Previous history of cold-related disease or previous incident
- Age extremes (very young, very old)
- Size: The smaller the animal the greater the risk
- Breed/Coat type: short-haired animals, or animals with a single coat
- Cold intolerance due to poor acclimatization to the environment (such as an Italian Greyhound in Maine)
- Where it happened: wet animal left in cold vehicle for over 15 minutes
- How it happened: following a car accident, falling through ice, falls, animal in shock and/or animals left outside without proper shelter on cold days/nights
- Health Condition: diabetic animals, recent surgical procedures, and the following pre-existing conditions: heart, respiratory, renal and/or liver failure
- Kirk and Bistner’s Handbook of Veterinary Procedures and Emergency Treatment by Richard B Ford & Elisa M Mazzaferro
- Textbook of Respiratory Disease in Dogs & Cats by Lesley G. King