Heatwave Emergency: Why is it crucial to remove a collar from a dog suffering from hyperthermia?

When summer arrives and the thermometer crosses the 30°C mark, the specter of heatstroke looms over all dog owners. Unlike humans, dogs do not have a generalized cutaneous sweating system to regulate their internal temperature. Their thermal balance is precarious and depends almost exclusively on localized respiratory and vascular mechanisms.

If your pet shows signs of exhaustion, pants frantically, or enters a critical phase of hyperthermia, every second counts to bring their body temperature down below the lethal threshold of 40.5°C. Among the first aid actions provided, one anatomical gesture is too often neglected or delayed: the immediate liberation of the neck. Understanding why you must remove a collar from a dog with hyperthermia is not just a comfort recommendation; it is an urgent medical requirement. Colliers & Compagnons explains the physiological foundations of this vital reflex.

Canine thermal physiology: An ultra-localized cooling system

To understand the urgency of freeing the animal's neck, it is essential to delve into the thermal biomechanics of the canine species. Dogs use extremely restricted heat dissipation pathways compared to ours.

Lack of generalized cutaneous sweating in canids

Dogs only have sweat glands (eccrine glands) on their paw pads. This exchange surface is tiny and completely insufficient to evacuate overall excess heat. The main driver of canine cooling is pulmonary evaporation through panting. By inhaling through the nose and exhaling through the mouth, warm, moisture-laden air escapes, while saliva evaporates on the tongue, capillarily cooling the superficial blood vessels of the oral cavity.

The crucial role of the major vascular axes of the neck

The dog's neck houses the body's thermal highway: the carotid arteries (which carry warm blood to the brain) and the jugular veins (which bring blood back to the heart). It is precisely at this point that the body organizes a counter-current heat exchange to cool cerebral blood and prevent edema or hypoxia. The cervical region is a true biological "cooling plate."

Clinical note: Immediate collar removal (Curve B) allows for the start of cranial temperature decrease from the 5th minute by restoring jugular flow.

Why leaving the collar on mechanically worsens hyperthermia

When a dog enters hyperthermia, its heart rate accelerates, and blood pressure increases in an attempt to send as much blood as possible to the periphery to dissipate heat. Keeping an accessory around the neck creates two major physical obstacles.

The thermal tourniquet effect on the jugular veins and carotid arteries

Under the effect of exertion or respiratory distress, the soft tissues of the dog's neck swell slightly. A collar that was initially fitted correctly suddenly becomes too tight. This constriction creates mechanical compression of the jugular veins. Overheated blood from the trunk continues to flow in through the deep carotid arteries, but its return through the superficial venous networks is hindered. Blood stagnates in the cranial cavity, dramatically accelerating cerebral overheating and increasing the risk of seizures.

Caloric retention of heavy materials (leather, thick nylon)

Traditional padded leather collars or double-layer nylon straps are excellent thermal insulators. Normally, this is not an issue. During a heatwave, these accessories act like an insulating scarf that traps the body's radiant heat. Furthermore, if you try to cool the dog by pouring water over its body, the thick collar will act as a shield, preventing cool water from coming into direct contact with the thin skin of the neck and cooling the deep blood flow.

Emergency veterinary protocol for heatstroke

If you suspect heatstroke (loud panting, thick drool, dark red or purplish gums, wobbly gait), you must immediately apply the step-by-step cooling protocol, staying away from any source of stress:

1. Total anatomical release: Instantly remove the collar, harness, or muzzle. The neck and chest must be completely free of any textile or metallic constraint.
2. Shade and ventilation: Immediately place the dog in a cool, ventilated area (in the shade of a tree, in an air-conditioned room, or in front of a fan).
3. Progressive hydrotherapy: Wet the dog with lukewarm water (around 20-25°C). Start with the paws, then the inner thighs (femoral artery area), the underside of the belly, and finally **the neck and nape** to directly target the jugulars.
4. Controlled hydration: If the animal is fully conscious, offer it fresh water, but never force it to drink to avoid pulmonary aspiration.

Common cooling mistakes to absolutely avoid

In the panic of an emergency, many owners make physical logic errors that can worsen the dog's clinical condition or cause death from cardio-respiratory arrest.

Using ice water or ice cubes: the trap of peripheral vasoconstriction

This is the most frequent and dangerous mistake. Pouring ice water or applying ice packs directly to the body of a hyperthermic dog triggers an immediate neurological mechanism: peripheral vasoconstriction. The small blood vessels of the skin instantly close under the effect of extreme cold. The hot blood then becomes "trapped" inside vital organs (heart, liver, kidneys, brain), which causes the central internal temperature to rise instead of falling.

Covering the dog with a wet towel and letting it sit

Placing a wet towel on the dog's back is a good idea for the first 30 seconds. However, if you leave this towel on without renewing it, it will quickly warm up on contact with the body and create a greenhouse or thermal dome effect. The warm towel prevents the natural evaporation of water and blocks cool air, transforming the skin area into a steam room that accelerates hyperthermia. Prefer continuous runoff of lukewarm water combined with a fan airflow.

Anticipating summer: Which materials to prioritize to avoid overheating?

For dogs that spend long months outdoors or engage in dynamic summer activities, the choice of daily accessory material becomes a full-fledged preventive health factor.

To limit heat accumulation around the vascular areas of the neck and facilitate quick drying during preventive showers, it is highly recommended to equip with a lightweight, waterproof Biothane collar. Unlike thick braided nylon straps that soak up sweat and warm water, creating a permanent warm compress, Biothane has a smooth, hydrophobic structure and minimal thickness. This ensures optimal heat dissipation by air convection, while allowing instant removal thanks to its constant mechanical flexibility, even in high heat.

Conclusion

Removing the collar during a canine hyperthermic crisis is not an option; it is a biomechanical emergency measure. Freeing the neck instantly restores blood flow to the jugular veins, thus ensuring blood return to the cooling areas and protecting the animal's cerebral neurological functions.

Heatstroke prevention requires constant attention, but also a judicious choice of your companion's equipment for the summer season. Opting for thin, hydrophobic, easy-to-detach accessories that do not store solar energy remains the best strategy to offer your dog a serene, cool, and safe summer. Faced with a heatwave, lightweight equipment is the primary guarantor of its health.

First aid and canine thermal analysis guide published on June 21, 2026.
In case of suspected heatstroke, immediately contact the nearest emergency veterinary center after initiating passive cooling of the animal.