By Roger W. Gfeller,
DVM, DipACVECC, Michael W. Thomas, DVM, and Isaac Mayo
Body temperature may
be elevated because of an infection (fever), but it may also increase because
of hot and/or humid conditions outside. An increased body temperature
caused by environmental conditions is commonly referred to as hyperthermia,
heatstroke, and heat prostration.
Hyperthermia may be a
life-threatening condition, and does require immediate treatment. A dog’s
normal body temperature is 101.5°F
plus or minus 1 degree Fahrenheit, and any time the body temperature is higher
than 105°F, a true emergency exists. Heatstroke generally occurs in hot
summer weather when dogs are left with inadequate ventilation in hot
vehicles. However, heatstroke may also occur in other conditions,
including:
1. When an animal is left outdoors in hot/humid
conditions without adequate shade.
2. When exercised in hot/humid weather.
3. When left in a car on a relatively cool (70°F)
day; a recent study from Stanford University Medical Center found the
temperature within a vehicle may increase by an average of 40
degrees Fahrenheit within one (!) hour regardless of outside
temperature.
Other predisposing factors may be obesity and/or
diseases affecting a pet’s airway. Keep in mind that prolonged seizures,
eclampsia (milk fever), poisonings, and many other conditions may cause
hyperthermia. Also, brachycephalic (short-nosed) breeds (Pekingese, Pug,
Lhasa apso, Boston terrier, etc.) may suffer from ineffectual panter syndrome
that results in an increased body temperature that may be fatal.
What to Do
• Remove your pet from the environment where the
hyperthermia occurred.
• Move your pet to shaded and cool environment, and
direct a fan on her.
• If possible, determine rectal temperature and
record it.
• Begin to cool the body by placing cool, wet
towels over the back of the neck, in the armpits, and in the groin
region. You may also wet the ear flaps and paws with cool water.
Directing a fan on these wetted areas will help to speed evaporative
cooling. Transport to the closest veterinary facility immediately.
What NOT to Do
• Do not use cold water or ice for cooling.
• Do not overcool the pet.
• Most pets with hyperthermia have body temperatures
greater than 105°F, and a reasonable goal of cooling is to
reduce your pet’s body temperature to 102.5-103°F
while transporting her to the closest veterinary facility.
• Do not attempt to force water into your pet’s
mouth, but you may have fresh cool water ready to offer should your pet be
alert and show an interest in drinking.
• Do not leave your pet unattended for any length
of time.
Rapidly cooling the pet is extremely important. While ice or cold water may seem logical, its use is not advised. Cooling the innermost structures of the body will actually be delayed, as ice or cold water will cause superficial blood vessels to shrink, effectively forming an insulating layer of tissue to hold the heat inside. Tap water is more suitable for effective cooling.
Severe hyperthermia is a disease that affects
nearly every system in the body. Simply lowering the body temperature fails to
address the potentially catastrophic events that often accompany this disorder.
A pet suffering from hyperthermia should be seen by a veterinarian as soon as
possible.
Date Published: 12/31/1994
Date Reviewed/Revised:
8/17/2009