Preventing Heat Stroke: Dogs' Vulnerability And Quick Onset

Dogs are susceptible to heat stroke, also known as hyperthermia, due to their limited ability to regulate body temperature. Unlike humans, dogs have fewer sweat glands located only in their footpads and noses, relying primarily on panting and breathing to cool down. This makes them vulnerable to heat stroke, especially in hot and humid conditions. Leaving a dog in a car, even on a mild day, can lead to a rapid increase in body temperature, and it only takes a few minutes for them to overheat and suffer fatal consequences. Recognizing early signs, such as heavy panting, rapid breathing, and dry mucous membranes, is crucial to prevent heat stroke, which can be life-threatening and cause serious complications.

Dogs' cooling mechanisms

Dogs have four main mechanisms to cool down: convection, evaporation, radiation, and conduction.

Convection occurs when dogs' body heat is lost through a fluid, such as air or water. When fluid molecules flow across the skin, heat is transferred.

Evaporation happens through panting and sweating. While humans have eccrine glands (which secrete sweat for temperature control) all over their bodies, dogs only have these glands in their paw pads. Dogs' main sweat gland, which is found all over their bodies, is the apocrine gland, which releases pheromones to communicate with other dogs. Therefore, dogs' primary way of losing heat through evaporation is by panting.

Radiation occurs when dogs' body temperatures rise, causing blood vessels in the skin to dilate, which results in increased blood flow. Blood is directed towards the skin, where excess body heat is released into the environment. About 40% of a dog's body surface heat loss happens through radiation alone.

Conduction happens when dogs come into physical contact with another body or object, such as when a dog lies down on a cold floor to cool down.

Additionally, blood vessels in dogs' faces, ears, and feet can expand, helping to dispel heat from the body.

Heat stroke symptoms

Heat stroke is a life-threatening condition that can result in serious complications and even death. Recognizing the early signs of heat stroke is crucial to prevent the condition from worsening.

The first sign of heat-induced illness in dogs is typically heat cramps, characterized by muscle spasms and related to dehydration and electrolyte depletion. This may progress to heat exhaustion, which is marked by fatigue, weakness, vomiting, and diarrhea.

As the dog's condition worsens, they may exhibit signs of heat stroke, which include:

• Heavy panting and rapid breathing
• Excessive drooling
• Dry mucous membranes
• Bright red gums and tongue
• Skin that is hot to the touch
• Increased heart rate
• Hyperactivity and difficulty maintaining balance
• Signs of shock, such as pale mucous membranes and white or blue gums
• Very rapid heart rate and low blood pressure
• Hyperventilation and severe dehydration
• Pupil dilation and irregular pulse
• Muscle tremors and lethargy
• Inability to move, uncontrollable urination or defecation
• Collapse and coma

If you notice any of these symptoms in your dog, it is important to take immediate action to cool them down and seek veterinary treatment.

Additionally, some dogs are more prone to heat stroke than others. Factors that increase the risk include age (very young or old), weight (overweight or obese), breed (long-haired or brachycephalic), physical fitness, medical disorders, and environment.

Heat stroke treatment

Heat stroke is a serious, sometimes fatal, condition that requires immediate medical attention. If you suspect your dog is suffering from heat stroke, call your veterinarian or nearest emergency animal hospital and inform them that you are on your way.

While en route to the veterinarian, it is important to start cooling your dog's body temperature down. Move your dog to a cool room or into the shade, and gently pour cool water (not cold) over their head, stomach, armpits, and feet. You can also apply cool cloths to these areas, ensuring that you continually replace them so that they do not start to retain heat. Do not use ice, as this may cause a drop in blood pressure and further damage to organs. You can also place a cold wet towel on their back, or wrap an ice pack or frozen vegetables in a towel and place it between their thighs.

It is important to keep your dog calm and offer them a drink of cool water, but do not force them to drink if they do not want to. You should also ensure a continuous flow of air across your dog to help increase evaporative heat loss.

Once you arrive at the veterinary hospital, your dog will be monitored and treated by a veterinarian. Treatment may include intravenous fluids, mild sedation, and low-concentration oxygen therapy. Medication may also be given to prevent or reduce symptoms such as vomiting, diarrhoea, and seizures.

The prognosis for heat stroke depends on how high the dog's body temperature elevated, how long the hyperthermia persisted, and the physical condition of the dog prior to the heat stroke. If treated immediately, most healthy dogs will recover quickly. However, some dogs may experience permanent organ damage or even death as a result of complications that develop secondary to hyperthermia.

Risk factors

Heatstroke is a life-threatening condition that can affect dogs and is often the result of exposure to excessive heat or extreme weather conditions. While all dogs are susceptible to heatstroke, certain risk factors can increase the likelihood of a dog developing this condition. Here are some key risk factors to be aware of:

Breed

Brachycephalic breeds, or short-nosed dogs with flattened faces such as pugs, boxers, bulldogs, and French bulldogs, are at a higher risk of heatstroke due to their restricted airways. Their smaller nostrils, long soft palate, and underdeveloped airways make it difficult for them to cool themselves by panting, which is the primary way dogs regulate their body temperature.

Age

Very young puppies and older dogs are more susceptible to heatstroke. Puppies under six months of age have not yet fully developed the ability to regulate their body temperature, while older dogs may have health conditions or reduced mobility that make it more challenging to cool down.

Weight

Overweight and obese dogs are at an increased risk of heatstroke. Carrying extra weight can make it more difficult for dogs to dissipate heat, and obesity can exacerbate underlying health issues that may contribute to heatstroke.

Medical Conditions

Underlying medical conditions can make it more difficult for dogs to regulate their body temperature and increase their risk of heatstroke. Some common conditions that may contribute include hypothyroidism, cardiac disease, laryngeal paralysis, tracheal collapse, and neurological diseases.

Environment

The environment plays a crucial role in the development of heatstroke. Dogs left in closed vehicles, even on mild days, are at a high risk due to the rapid rise in temperature. Similarly, dogs confined to crates or exercise pens without adequate ventilation, shade, or water access can quickly succumb to heatstroke. Additionally, dogs left in hot, closed homes or garages without air conditioning are at risk, especially if they are not accustomed to hot weather.

Exercise and Activity

Exercising or engaging in strenuous activity during the hottest times of the day can put dogs at risk of heatstroke. Even short walks or moderate exercise in extreme heat can be dangerous. It is important to provide frequent breaks, access to shade, and plenty of cool water to help prevent overheating.

Acclimation

A sudden change to a warmer climate or exposure to hot weather without proper acclimation can increase the risk of heatstroke. Dogs typically need time to adjust to significant temperature changes, and a rapid increase in ambient temperature can overwhelm their cooling mechanisms.

Water Access

Inadequate access to water or not drinking enough can lead to overheating and heatstroke. It is important to ensure that dogs have access to fresh, cool water at all times, especially during warm weather.

Muzzles

The use of muzzles can restrict a dog's ability to pant, which is their primary method of cooling down. If a dog is muzzled for any reason, extra caution should be taken to ensure they do not overheat, especially in warm environments.

Grooming

The length and thickness of a dog's coat can impact their ability to regulate body temperature. Long or thick coats can retain heat, making it more difficult for the dog to cool down. However, clipping or shaving a dog's coat should be done with caution, as a short coat may not provide sufficient protection from the sun.

Medications

Certain medications can increase a dog's susceptibility to heatstroke by interfering with their ability to regulate body temperature or affecting their tolerance to heat. Always consult a veterinarian if your dog is taking any medications, especially if you plan to expose them to warm environments or strenuous activity.

Previous Heatstroke

Dogs that have previously experienced heatstroke are more likely to suffer from it again. The damage caused by heatstroke can affect the thermoregulatory center, making it more difficult for the dog's body to maintain a normal temperature.

It is important for dog owners to be vigilant and take proactive measures to prevent heatstroke, especially during warm weather. Providing shade, ample water, and opportunities for cooling off is crucial. Additionally, knowing the signs of heatstroke and seeking immediate veterinary attention if symptoms arise can help improve the outcome and reduce the risk of permanent organ damage or other serious complications.

Prevention

Heat stroke is a serious and life-threatening condition in dogs. It can occur very quickly, even when the temperature doesn't seem too hot, and can result in death in under an hour. Therefore, it is important to take preventive measures to protect your dog from heat stroke. Here are some key strategies for prevention:

Provide Shade and Water

Always ensure your dog has access to shade and fresh drinking water when outdoors, especially during the warmer months. This is crucial, as dogs primarily cool themselves down by panting and breathing, and shade helps prevent their body temperature from rising too high.

Exercise During Cooler Times

Limit your dog's outdoor activity to the cooler parts of the day, such as early morning or dusk. Even short walks or exercise during the hottest parts of the day can lead to heat stroke, especially for dogs predisposed to heat-related illnesses. Avoid exercising your dog in hot and humid weather, as they can develop heat stroke even during relatively short periods of outdoor activity.

Avoid Leaving Dogs in Cars

Never leave your dog alone in a car, even on seemingly cool days or with the windows partially open. The temperature inside a car can increase by 40°F per hour, and cracking the windows or parking in the shade may not be enough to significantly reduce the temperature. Dogs can quickly overheat in a car, even if the outside temperature seems mild, as they cannot cool off effectively in such an enclosed space.

Keep Dogs Indoors During Extreme Heat

On extremely hot days, keep your dog indoors in an air-conditioned environment. This is especially important for dogs that are more susceptible to heat-related illnesses, such as older dogs, obese dogs, or those with pre-existing medical conditions like heart disease or tracheal collapse.

Use Dog-Safe Sunscreen

Apply dog-safe sunscreen to light-haired and pink-skinned dogs to protect them from sunburn. Sunburn can increase the chances of heat illness and put your dog at risk for skin cancer. Areas that are particularly vulnerable to sun damage include the ears, nose, and eyelids.

Be Cautious with Grooming

When it comes to grooming, expert recommendations vary. The ASPCA suggests that trimming the fur of double-coated dogs may help with heat management, but it's important to leave at least one inch of coat to provide insulation and protection from sunburn. For long-haired dogs with a single coat, clipping is generally not recommended, as their coats may not be dense enough to protect them from the sun if cut too short.

Monitor for Early Signs

Recognizing the early signs of heat stress or heat exhaustion can help you take preventive measures before your dog develops heat stroke. Early signs include heavy panting, rapid breathing, excessive drooling, dry mucous membranes, bright red gums and tongue, and a higher heart rate. If you notice these signs, take steps to cool your dog down and provide access to shade and water.

Frequently asked questions