Dog Hypothermia
What Is Dog Hypothermia?
Simply put, hypothermia describes the situation where a dog’s body temperature is significantly lower than normal. The drop in body temperature must be dramatic enough to put the dog’s well-being at risk, however. Being cold isn’t the same as being hypothermic.
What Is a Normal Body Temperature for a Dog?
The average body temperature for dogs is warmer than what is normal for people—around 101.5 ˚F, give or take a degree (100.5-102.5°F or 38-39.2°C).
When Is a Dog’s Temperature Too Low?
When a dog’s body temperature drops to around 98˚F or 99˚F (37°C), hypothermia is setting in.
Symptoms of Dog Hypothermia
Initially, a dog’s body responds to hypothermia by narrowing blood vessels near the surface to send blood away from the skin, legs, ears, feet, etc., and towards essential organs like the brain and the heart. Here are the symptoms of hypothermia in dogs, from mild to severe.
Signs of mild to moderate hypothermia in dogs include:
As hypothermia worsens, dogs will:
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Stop shivering
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Collapse
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Have fixed and dilated pupils
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Develop slow and irregular heart and breathing rates
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Become comatose
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Potentially die
Mild Hypothermia
At this point, you may notice that a hypothermic dog’s extremities (ears, legs, feet, paws) appear somewhat pale and feel cool to the touch. While this physiological response can certainly help a dog survive, it does increase the risk that they’ll suffer from frostbite as time goes on.
Look for:
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Cold areas of the body, especially the extremities (ears, legs, feet, paws)
Moderate Hypothermia
To generate extra heat, a dog with mild to moderate hypothermia will shiver, and their muscles will become tense. This muscular activity produces warmth, but it can also make a dog’s movements stiff and clumsy.
At this point, a hypothermic dog may become sluggish and seem confused.
Look for:
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Shivering
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Stiff or clumsy movements; difficulty walking
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Sluggishness
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Seeming confused
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Pale gums
Severe Hypothermia
As severe hypothermia sets in, a dog will stop shivering because their muscle cells have run out of energy.
Once shivering stops, the dog’s body temperature may begin to rapidly drop.
The chemical reactions that are necessary for normal body functioning in a dog will slow down or stop altogether. The dog’s heart rate slows and becomes erratic, and their breathing slows. As oxygen levels drop in the bloodstream, the dog will become increasingly lethargic and unresponsive.
Eventually shock, organ failure, coma, and death will follow.
Look for:
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Shivering that has stopped
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Rapid drop in body temperature
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Slower breathing
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Collapsing
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Lethargic and/or unresponsive
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Fixed and dilated pupils
Causes of Dog Hypothermia
Exposure to cold temperatures is the most obvious cause of hypothermia in dogs, particularly if it’s also windy or the dog becomes damp, but there are other causes of dog hypothermia as well.
Hypothermia and Cold Weather
Certain dogs are at higher risk for exposure-related hypothermia than others. These include elderly dogs, puppies, small dogs, and dogs who have short or thin coats or are unused to cold temperatures. All these factors, especially in combination, make it harder for dogs to keep themselves warm when temperatures drop.
Hypothermia and Anesthesia/Surgery
Veterinarians often have to take measures to prevent or treat hypothermia in dogs who are in the hospital for anesthesia and surgery.1
Drugs and procedures used to anesthetize dogs can lead to increased heat loss through the skin and respiratory tract and reduce the body’s ability to respond appropriately.
Surgery can result in more heat loss because:
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The dog’s coat is shaved
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The dog’s skin is cleaned with cool antiseptic solutions
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The dog is laid on cold surgery tables
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Cool intravenous fluids are administered
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Internal organs are exposed to the air
Hypothermia and Sick or Injured Dogs
Sick and injured dogs are also at increased risk for become hypothermic.
Health problems like kidney disease, heart failure, diabetes mellitus, some types of poisonings, and bleeding due to trauma can all lead to heat loss and/or the inability to regulate body temperature.
How Vets Diagnose Dog Hypothermia
The diagnosis of hypothermia is based on a dog’s body temperature.
Using a rectal thermometer provides the most accurate measurements. Any dog with a rectal temperature of under 98-99˚F (37°C) is hypothermic and requires treatment. If a thermometer is unavailable, a vet can look at the dog’s symptoms to make a reasonable guess as to whether hypothermia is a likely diagnosis.
Treatment for Dog Hypothermia
Dogs with hypothermia need to be rewarmed, but the process should occur gradually. Think “warm,” not “hot.”
Do not use a heating pad, as it gives off excessive heat that can lead to burns, or it can direct too much blood flow towards the skin, which can worsen shock.
How to Slowly Warm a Hypothermic Dog
Here’s what to do if your dog has hypothermia:
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Get your dog into a warm building or vehicle.
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Wrap them in blankets, towels, coats, etc. If you can, warm up some blankets on a radiator, in a clothes dryer, or using a hairdryer.
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Place bottles of warm water next to your dog, but always keep a couple layers of fabric between the bottle and your dog’s skin.
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Get to the nearest veterinary office immediately.
Veterinary Treatment for Hypothermia in Dogs
Once your dog is at the clinic, the veterinarian can employ more aggressive warming techniques.
Hypothermic dogs can be given warmed intravenous fluids. Warmed fluids may be infused into a dog’s abdomen, stomach, and colon, and they may be given warmed and humidified oxygen to breathe.2
The veterinary team will closely monitor your dog’s body temperature, heart rate and rhythm, oxygenation, blood-glucose levels, and many other parameters so problems can be managed as they arise.
Additional treatments directed towards any underlying health problems will be necessary for dogs who develop hypothermia as a result illness or injury.
Recovery and Management of Dog Hypothermia
Dogs with mild to moderate hypothermia should survive as long as they quickly receive appropriate treatment.
Severe hypothermia carries a worse prognosis, but some dogs can be revived even if they are comatose, in part because low temperatures reduce the oxygen and energy needs of cells in the body.
There is no way to know how a dog will respond to rewarming without trying, so always get a hypothermic dog to a veterinary hospital as quickly as possible.3
Dog Hypothermia FAQs
How do you know if your dog has hypothermia?
Signs of mild to moderate hypothermia in dogs include:
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Shivering
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Muscle stiffness
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Lethargy
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Difficulty walking
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Pale gums
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Cool body surfaces
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Confusion
As hypothermia worsens, dogs will:
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Stop shivering
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Collapse
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Have fixed and dilated pupils
-
Develop slow and irregular heart and breathing rates
-
Become comatose
-
Potentially die
How cold does it have to be for a dog to get hypothermia?
Different dogs are at risk for hypothermia at different temperatures based on their size, age, health status, coat type, and other factors.
In general, temperatures over 45° F should be safe for most dogs unless it is very windy, or the dog becomes wet.
Pay special attention to your dog’s well-being when temperatures drop below freezing.
How do you bring a dog's temperature up?
Get the dog into a warm building or vehicle and wrap them in blankets, towels, coats, or anything else you might have available.
If you have access to a clothes dryer or something similar, you can also warm up the blankets to help. Place warm water bottles next to the dog, but keep a couple layers of fabric between the bottle and the dog’s skin.
Get to the nearest veterinary office immediately.
References
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Stuart C. Clark-Price, Berit L. Fischer, Kevin L. Kirwin, Stephanie C. J. Keating, Adam Auckburally, Derek Flaherty, Multicenter study to investigate factors associated with change in rectal temperature during anesthesia in dogs, Journal of the American Veterinary Medical Association, 10.2460/javma.258.1.64, 258, 1, (64-71), (2021).
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Brodeur A, Wright A, Cortes Y. Hypothermia and targeted temperature management in cats and dogs. J Vet Emerg Crit Care (San Antonio). 2017 Mar;27(2):151-163. doi: 10.1111/vec.12572. Epub 2017 Jan 25. PMID: 28122159.
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Hilmo J, Naesheim T, Gilbert M. "Nobody is dead until warm and dead": prolonged resuscitation is warranted in arrested hypothermic victims also in remote areas--a retrospective study from northern Norway. Resuscitation. 2014 Sep;85(9):1204-11. doi: 10.1016/j.resuscitation.2014.04.029. Epub 2014 Jun 2. PMID: 24882104.