Heat stroke in dogs is a veterinary emergency that kills hundreds of dogs annually in the UK and is almost entirely preventable through owner education about temperature risk and appropriate precautions.
Heat stroke causes brain damage, organ failure, and death through a cascade of physiological failures triggered by core temperature elevation. The suffering involved is severe with distressed panting, collapse, and seizures. Recovery is possible if treatment is immediate but long-term neurological damage is common in survivors. Every heat stroke death is preventable as the risk factors are well understood and avoidable.