Three summers ago, a couple brought in their two-year-old French Bulldog after a 20-minute walk. Twenty minutes. The outside temperature was 88 degrees Fahrenheit, the sidewalk was radiating stored heat, and the dog — with his compressed nasal passages and limited ability to cool himself — had a rectal temperature of 108.4 F when we checked it in the exam room.
He survived. Barely. Three days in the ICU, disseminated intravascular coagulation on day two, and renal values that took a week to normalize. All from a walk that, to the owners, seemed perfectly reasonable.
Environmental emergencies catch people off guard because the environment doesn't feel dangerous to humans. We sweat efficiently, we wear shoes on hot pavement, we shiver ourselves warm. Pets don't have those luxuries.
Heatstroke
Dogs cool primarily through panting — evaporating moisture from the tongue and respiratory tract. It's a surprisingly inefficient system compared to human sweating, and it fails in high humidity (the moisture can't evaporate) and in brachycephalic breeds (the airways are too compromised to move enough air).
A body temperature above 104 F (40 C) after activity in heat is concerning. Above 106 F (41.1 C) is dangerous. Above 108 F (42.2 C) causes cellular damage, organ failure, and death.
What to do immediately:
- Move the pet to a shaded, cool area. Indoors with air conditioning is ideal.
- Wet the pet with cool (not ice-cold) water — focus on the neck, armpits, and groin where blood vessels are close to the surface. You can use wet towels, but replace them frequently; towels insulate when they warm up.
- Direct a fan at the wet fur to enhance evaporative cooling.
- Offer small amounts of cool water to drink. Don't force it.
- Take a rectal temperature every five minutes if you have a thermometer. Stop active cooling once the temperature drops to 103.5 F — overcooling is a real risk and can cause hypothermia.
- Transport to the vet even if the pet seems to recover. Internal organ damage from heatstroke isn't always immediately apparent.
What not to do: Ice baths cause peripheral vasoconstriction — the blood vessels at the surface clamp down, trapping heat in the core. Cold water on the head can cause brain vessel constriction. Neither helps. Cool water, not cold.
Brachycephalic breeds, overweight dogs, dogs with thick coats, elderly pets, and dogs with existing heart or respiratory conditions are at highest risk. But I've treated athletic, young, lean dogs who overheated during intense exercise on warm days too. The "fit dog" myth — that a healthy dog can handle anything — isn't true.
Hypothermia
The opposite end, and less commonly discussed but no less dangerous. For related context, see poisoning in pets: common toxins.
Normal body temperature in dogs and cats is 101 to 102.5 F. Hypothermia begins below 99 F (37.2 C). Moderate hypothermia (below 95 F) causes bradycardia (dangerously slow heart rate), altered consciousness, and eventually cardiac arrhythmias. Severe hypothermia (below 90 F) is life-threatening.
Small dogs, toy breeds, senior pets, puppies and kittens, pets with short coats, and animals with underlying illness are most vulnerable. A wet pet loses body heat dramatically faster than a dry one — a dog who fell through ice or was caught in cold rain is in far more danger than a dry dog in the same temperature.
Warming protocols:
- Move the pet indoors. Remove any wet collars, harnesses, or clothing.
- Dry the coat thoroughly.
- Wrap in warm blankets. Place warm (not hot) water bottles wrapped in towels against the neck, armpits, and groin. A heating pad on the lowest setting, with a towel between it and the pet, works but must be monitored constantly — hypothermic pets can't feel burns on their skin, and contact burns from unprotected heating pads are a legitimate risk.
- Do NOT use a hairdryer directly on the pet or immerse them in hot water. Rapid external warming dilates peripheral blood vessels and can cause blood pressure to crash.
- Monitor temperature. Warm slowly — a rise of one to two degrees per hour is appropriate.
- Offer warm (not hot) water or broth once the pet is conscious and alert.
Severe hypothermia requires veterinary intervention — warm IV fluids, warm water lavage, and cardiac monitoring. Core rewarming in the hospital is safer than external rewarming at home for severely affected animals.
Near-Drowning
Pets can drown in swimming pools, ponds, bathtubs, and even water bowls (for very small puppies or kittens). Dogs who can't find the pool exit, elderly dogs with mobility issues, and brachycephalic breeds who fatigue quickly in water are at highest risk.
Immediate response:
- Remove the pet from water. Be careful with your own safety — a panicking dog can pull you under.
- For a small pet, hold them upside down briefly (10 to 15 seconds) to allow water to drain from the airways. For a large dog, lay them on their side with the head lower than the body.
- Check for breathing. If absent, clear the mouth of debris and begin rescue breathing — close the mouth, form a seal over the nostrils, and blow gently until you see the chest rise. Five breaths, check for a heartbeat, continue if needed.
- Even if the pet starts breathing, they need emergency veterinary care. Water in the lungs causes inflammation and can lead to secondary drowning (pulmonary edema) hours later.
I learned about secondary drowning early in my career when a dog who'd been submerged for less than a minute seemed completely normal at the scene. The owner declined to come in. The dog developed respiratory distress at home that evening. Excessive panting in dogs was the first sign — heavy breathing that wouldn't resolve, then coughing, then labored effort. By the time they arrived at the ER, the dog had significant pulmonary edema.
The Common Thread
All three environmental emergencies share a pattern: they start with something that seems manageable and escalate when people underestimate the timeline. A "quick walk" in the heat. "He's a strong swimmer." "She's only been outside for 30 minutes."
The body has compensatory mechanisms that buy time — panting harder, shivering harder, coughing out water. But those mechanisms have limits, and once they fail, the decline is steep. Recognizing pet emergencies from environmental causes means paying attention to the early signs — before the pet stops compensating — and acting on what you see rather than waiting for something dramatic to happen.