A new study by the VetCompass team at the Royal Veterinary College has found that dogs with heatstroke may be suffering even further due to outdated first aid practices.
The research calls for updated guidance to be promoted more widely for dogs with heatstroke – including cold water immersion and using fans or air conditioning on soaked dogs – to support owners to provide the best possible care.
Heat-related illnesses (HRI) such as heatstroke are potentially fatal for dogs and can occur following exercise or from exposure to hot environments. While many risk factors can increase the probability of HRI occurring, the priority is to cool dogs early and to ensure rapid reduction in their core body temperature to limit disease progression.
Veterinary surgeons and canine scientists from the RVC, Scotland's Rural College and emergency veterinary care provider, Vets Now, conducted a study into HRI using data from a cohort of 945,543 dogs under primary veterinary care at 886 UK veterinary practices between 2016 and 2018. Overall, 856 dogs presented for veterinary management of HRI.
The findings showed less than a quarter (21.7%) of the dogs presented with heatstroke to UK vets during this period had been actively cooled before being transported to the veterinary clinic, and only 24% of these dogs had been cooled using currently recommended methods of either immersion or soaking combined with air movement. More than half (51.3%) of these cooled dogs had been cooled using outdated advice by applying wet towels. While better than no active cooling, the application of wet towels is not nearly as effective as water immersion or evaporative cooling for rapid and steep reduction in body temperature.
Many websites continue to offer outdated first aid advice to dog owners that recommend “slow” cooling using “tepid but not cold water”, despite no substantial evidence to support this guidance. Similar myths about using tepid water in human medicine have been dispelled by extensive research demonstrating that cold water immersion and evaporative cooling are the most effective treatments for heatstroke. The VetCompass study also showed there had been no increase in the use of recommended cooling methods over the three-year study period, despite the publication of the recommended guidelines in 2016 by the American College of Veterinary Emergency and Critical Care’s Veterinary Committee on Trauma.
This new research calls for first aid advice to be updated to the current best practice veterinary guidelines which recommend to “cool first, transport second” as the immediate first aid response for dogs with heatstroke. Recommended cooling methods include cold water immersion for young, healthy dogs, or pouring water of any temperature that is cooler than the dog over them combined with air movement from a breeze, fan, or air conditioning (evaporative cooling) for older dogs or dogs with underlying health problems. Owners should also seek veterinary advice as soon as possible.
Emily Hall, Lecturer in Veterinary Education at the RVC, and lead author of the paper, said: “The key message for dog owners is to cool the dog quickly, using whatever water you have available provided the water is cooler than the dog. The longer a dog’s body temperature remains elevated, the more damage can occur so the sooner you can stop the temperature rise and start cooling the better.”
Anne Carter, Senior Lecturer in Animal Science at SRUC, and co-author of the paper, said: “It takes time to put research into practice, and this can be harder when you’re faced with long-standing myths. We urge veterinary professionals, dog owners and any sources of first aid advice to review the recommendations on cooling methods, dispel the myths and promote the message to ‘cool first, transport second’.”
Dan O’Neill, Associate Professor in Companion Animal Epidemiology at the RVC, and co-author of the paper, said: “Our previous research** showed that 97% of dogs treated for mild heat-related illness survived while only 43% of dogs treated for severe heat-related illness (heatstroke) survived. The data are very clear; acting early to cool dogs as soon as mild signs of overheating are observed will save lives. During exercise in warm weather, if your dog pants excessively, has difficulty breathing, or becomes unwilling or unable to continue exercising, then you should stop the exercise, seek shade, cool them with water and seek veterinary advice.”
Amy Luker, Senior Training Veterinary Surgeon at Dogs Trust, said: "Dogs Trust is delighted to have provided funding for this latest study by the Royal Veterinary College into the complex area of heatstroke. Our Canine Welfare Grant programme provides funding for research projects with clear pathways to positive welfare outcomes. This latest study further extends our knowledge of the most effective way to treat dogs presenting with heatstroke symptoms, information that will help formulate advice given to vets and dog owners moving forward and undoubtedly help save the lives of many dogs in the years to come."
