Hypothermia and Frostbite in Dogs

Hypothermia and frostbite are two potential problems your dog can suffer from in winter .

Both occur when your dog has been exposed to the cold for too long, and whilst hypothermia and frostbite are treatable they may leave lasting tissue damage if the symptoms are not spotted and treated promptly.

Which dogs are most susceptible ?

• short haired dogs;
• small dogs;
• wet dogs;
• dogs sensitive to cold weather; and
• dogs that are outside for long periods of time who do not have access to warm and dry shelter.

Why – because for one reason or another (be it an environmental, genetic or health reason) these dogs find it more difficult to keep their bodies at their normal temperature than dogs who don’t fall into any of these categories.

Hypothermia

- What is hypothermia?

Hypothermia occurs when your dog’s temperature falls, and stays, below its normal range of 100.5 to 102.5 degrees Fahrenheit .

When your dog has hypothermia he is losing body heat faster than he can replace it . One way this can happen is when he’s walking outside – the heat from his paws will quickly transfer to the cold ground he is walking on. On a very cold day your dog wouldn’t need to take many steps before his paws are freezing cold because he won’t be able to replace the heat in his paws before it’s lost by treading on the cold ground again.

In cold weather your dog will constantly be trying to maintain his body temperature in its normal range. Dogs regulate their temperature either by conserving their body heat or by producing more body heat . The main ways they do this are similar to how we react to cold weather:

• shivering is the primary way dogs use to produce heat;
• piloerection is the dog equivalent to our goose bumps – with piloerection your dog’s hairs stand on end thereby trapping a layer of warmed air beneath them. This creates an additional layer of insulation between your dog’s body and the cold weather so helping him to conserve body heat; and
• vasoconstriction is another way your dog can conserve heat, and it’s the process whereby his blood vessels narrow to restrict the amount of blood (heat) that flows through them. The aim of vasoconstriction is to keep the blood flowing to those parts of your dog’s body that are the most important for his survival (brain, liver, lungs etc) at the expense of the peripheral areas (toes, ears and tail).

- What are the symptoms of hypothermia?

The symptoms of hypothermia include:

• shivering;
• lethargy;
• muscle stiffness;
• lack of co-ordination;
• low heart and breathing rates;
• fixed and dilated pupils;
• collapse;
• coma

With mild hypothermia your dog is likely to be shivering and appear lethargic. As the hypothermia increases in severity the other symptoms become evident – effectively your dog becomes increasingly unresponsive as his body goes into heat conservation mode. At this time your dog’s focus will be on keeping his vital organs working by restricting the blood flow to all but these parts of his body. If it’s not treated, hypothermia can be fatal .

- Treating hypothermia

The treatment for hypothermia focuses on warming your dog up so that his core temperature returns to normal .

If you are out walking with your dog and you notice he is suffering from the cold, you need to prevent him losing further body heat. This is easily done when you have a small dog as you can pick him up and carry him home. With larger dogs, unless you are willing to give up your coat, the best you can do is make your way home as quickly as you can.

Once home here are the suggested ways to treat hypothermia.

If your dog has mild hypothermia – he’s shivering and his muscles seem stiff – move him to a warm room where the floor is well insulated and wrap your dog in a warm dry blanket.

Ideally keep him like this until his temperature returns to normal. If you don’t have a thermometer to take his temperature keep the blankets on him until he stops shivering, has more movement in his body, and appears to have returned to ‘normal’. However, taking your dog’s temperature is the only reliable way to confirm that his temperature has returned to normal.

For moderately severe hypothermia (your dog’s body temperature is approximately 90 – 94 degrees Fahrenheit) you will need to use rewarming sources to bring your dog’s temperature back to normal.

Rewarming sources include hot water bottles, warm towels, heat lamps, warm baths, hairdryers and heat pads. Don’t be tempted to use water that is too hot in an attempt to warm your dog up more quickly because you can easily burn his skin. The water temperature should be a few degrees above your dog’s normal body temperature, about 103 – 105 degrees Fahrenheit.

AS his skin warms up watch out for any adverse reaction from your dog as you’re handling him. Remember how your fingers can ache and start tingling a few minutes after you’ve come in from the cold? Your dog will have similar sensations and he may lash out and/or nip you as he’s unsure of what is happening to him.

Severe hypothermia requires immediate treatment from your vet and this usually involves internal warming achieved through warm water enemas, stomach flushes and other techniques.

Hypothermia can leave leave lasting damage because the lack of oxygenated blood flowing to body tissue can cause that tissue to breakdown. The extent of the damage will depend on how long your dog has been suffering from hypothermia, how low his temperature has fallen and the parts of the body affected.

If you have treated your dog for hypothermia a trip to the vet for a check up is essential for determining whether any permanent damage has occurred .

- Preventing hypothermia

Preventing hypothermia is much easier than treating it, so:

• don’t leave your dog outside for long periods of time without letting him have access to a warm dry shelter;
• if you do take your dog out for exercise during cold weather try to do it little and often and consider investing in a coat and booties for your dog;
• be particularly wary if your dog gets wet whilst you are out walking as the wind chill factor can cool him down much more quickly than you think (consider taking a towel with you on your walk so you can dry your dog off as you’re walking); and
• if your dog is sensitive to the cold only take him outside when he needs to relieve himself.

Frostbite

- What is frostbite?

Frostbite is the name given to tissue damage that is caused by exposure to extremely cold conditions .

As mentioned above, your dog conserves heat by reducing the amount of blood that flows to the peripheral parts of his body, such as his ears, paws and tail. With a lack of blood these areas are starved of warmth and oxygen and as a consequence ice crystals may form in the tissue which can then cause that tissue to die .

- Symptoms of frostbite

It’s not easy to spot frostbite as the areas affected are usually covered in hair. However, the signs to look out for are very pale skin which is very cold to the touch .

Commonly affected areas are dog toes, ear tips, tails and the scrotum area .

As the skin warms it will redden and swell, and be painful for your dog. After a few days the skin will dry up and look scaly. Depending on the severity of the frostbite dead tissue will slowly turn black and eventually slough off.

- Treating frostbite

Frostbitten areas need to be quickly warmed using similar methods to those used for treating moderate hypothermia.

Resist the urge to rub or massage the affected area as this can do more harm than good -massaging may release toxins that can further damage the tissue.

Take your dog to the vet as soon as you can so that he can start monitoring your dog to determine the extent of any tissue damage. Expect this monitoring to last several days as it takes time for the severity of the frostbite to reveal itself. During this time your vet is likely to prescribe pain killers and antibiotics to help ease your dog’s pain and look at removing any dead tissue.

In severe cases of frostbite your dog may need to have a limb, his tail or part of an ear amputated. The reason amputation is necessary is that dead and dying tissue attracts bacteria which can be life threatening for your dog.

- Preventing frostbite

• As with hypothermia, the way to prevent frostbite is to prevent your dog being outside in freezing temperatures for any length of time