Heatstroke in Dogs and Cats

We are increasingly experiencing severe heat waves in Germany, which also affect our dogs and cats. Dogs and cats have hardly any sweat glands and can only keep their body temperature constant by panting when exposed to heat.

Heatstroke is defined as reaching a body temperature of more than 41 degrees with the simultaneous presence of neurological disorders.

Probably everyone knows that leaving animals in the car in summer temperatures is a possible cause of heatstroke. Nevertheless, the danger is constantly underestimated. Even a supposedly short time alone in the car, not particularly high outside temperatures, or a slightly opened window do not prevent the risk of heatstroke.

Regardless, there are other causes that are often not so well known. These include overheating due to physical exertion in very warm surroundings (running alongside a bicycle, training) as well as overheating of old or sick animals or puppies whose ability to regulate body temperature is impaired. The risk of physical damage is increased by a lack of fluids, which can occur quickly due to prolonged panting.

Heatstroke is an emergency in animals as well as humans and is associated with a high mortality rate.

The first symptoms are severe panting, increased heart rate, and a drop in blood pressure, i.e., the pulse is high, weak, and difficult or impossible to feel. The cause is a disturbed heart function, which would be evident in an EKG. In a slightly more advanced stage, the animal appears weak, dazed, and disoriented. It staggers or lies on its side. In an advanced stage of heatstroke, vomiting and seizures occur. The cause of this is an increasing water retention (edema formation) in the brain.

Immediate measures and first aid by the pet owner should be:

The animal must be removed from the situation with high ambient temperature as quickly as possible. Immersing the entire body in ice water for 10–20 minutes has been shown to be the most effective method of lowering body temperature quickly. However, this method has some disadvantages. Apart from the fact that ice water is rarely available, it is extremely unpleasant for our animals. Furthermore, it reflexively leads to constriction of the blood vessels in the periphery of the body, to shivering, associated with heat generation inside the body.

Alternatively, the body can be moistened as completely as possible, except for the skin (!), so that heat is removed from the body through evaporation. Readily available mineral water could also be used. An increased draft can increase this effect.

If at all possible, the body temperature should be monitored, measured rectally. Antipyretic drugs should not be used.
Offering water or food should only take place when the animal is conscious again and the swallowing reflex is present. Infusing liquid without a swallowing reflex can lead to water and food components entering the airways and thus to aspiration pneumonia.

The animal should be presented to a veterinarian as soon as possible:

The veterinarian will supplement the measures by intravenously administering cold infusion solutions and, depending on the overall situation, sedatives (benzodiazepines). Diazepam has an anxiolytic, muscle-relaxing, anticonvulsant, and calming effect. Further measures to improve heart function, the internal environment, and the treatment of seizures are based on special examination findings (ECG, laboratory).

If damage has occurred to the brain and other organs such as the heart, kidneys, lungs, or liver, a longer, possibly outpatient, treatment is usually necessary.

You can also find more information on symptoms and first aid on our health portal at:
https://petsvetcheck.de/krankheiten-und-stoerungen/notfaelle/notfaelle-von-a-z/ueberhitzung-hyperthermie/
or in the book
https://www.hundebuchshop.com/Notfaelle-bei-Hund-und-Katze-Loewe.htm