24/06/2024
Emergency Cooling of Canine Heat Casualties: critical thinking
There has been lots of information going around on cooling hot dogs, some really good, some really bad!
With some of the new updated information (which isn't actually new) from professionals on the advised best methods of rapid cooling including cold-water immersion for young/healthy dogs, or evaporative cooling for older/unwell dogs there has been the usual comments on this being dangerous even though the available evidence and experience says otherwise.
Comments I've seen in the last 2 weeks include...
"I put cold-water on my dog once because he was overheating and he died, my vet said this was the wrong thing to do as it caused him to go into shock", "never put cold water on a hot dog it causes the blood vessels to constrict and has the opposite effect", "the race vets (leading ones at that) all say this is dangerous and is forbidden at international races".
In dogs, there are various reasons you hear (even from some vets) why you shouldn't use cold water, such as "Shock" or "Cold Water Shock" being the most common from pet owners, trainers, and sport dog owners etc. Cold-water causes peripheral vasoconstriction and slows down cooling being the most common from some vets. And sometimes DIC (a blood clotting disorder) which is caused by the heat damage, NOT cooling.
Let's take the following scenario...
A heatstroking dog arrives at an emergency vet clinic where the team are waiting, upon arrival they immediately begin rapid cooling measures with cold water to bring the dog's temperature down fast, but the dog dies.
Did the dog die because the water used for cooling was too cold and the dog's temperature was dropped too fast?
Some would say yes, but some people tend to lack the ability to critically evaluate a situation and see beyond what is right in front of them, it is extremely unlikely and association does not mean causation, before you come anywhere near that conclusion you have to look a little deeper and ask a few important questions such as...
1. How long was the dog above a critical temperature?
2. How long before the owner realised the dog was in trouble and sought help or began cooling measures?
3. Did the owner apply any active cooling measures before transport? What did they do? How long for?
4. If they did cool did they monitor temperature and stop cooling measures at a safe temp?
5. Is the owner telling the truth? Most vets will agree pet owners don't always tell the truth in these cases for various reasons, guilt, or being judged maybe?
6. Is that particular owner able to critically evaluate the situation?
All these things matter because it is generally well accepted in human and veterinary medicine that it is the length of time above a dangerous temperature that determines the chance of survival, and that temperature is different for different dogs.
Veterinary professionals also talk a lot about evidence based medicine, yet there has only been one study ever that compared the temperature of the water or the use of ice for external cooling in dogs, and it showed that ice water and cold water cooling were the fastest and most effective method of cooling. The concept that ice or cold water causes vasoconstriction and slows the cooling process has never been scientifically validated.
People worry about cooling when their first concern should be that the HEAT is the immediate life threat and you need to get it down to a safe temperature fast, and the earlier you recognise the signs and start cooling measures the better the chance of survival.
Vets generally work in a clinic or hospital, they see patients after the event, when what often determines outcome is what you do in the field at point of injury, it used to be the accepted practice to get to a vet fast, now it's becoming more widely accepted to cool before transport because again it is length of time they are above a critical temperature.
Added to this a lot of what has been taught, and is still being taught in veterinary medicine including first aid is all based on clinical medicine, not field medicine which is a completely different environment and although not always a huge deal clinical medicine doesn't always translate well to the field setting. There is not and has never been any formal training in prehospital care in the veterinary industry, it doesn't exist (unlike human medicine).
However over the last decade or so and mostly in the US there has been a lot of work to establish guidelines and training, with the Veterinary Committee on Trauma (VetCOT) publishing their best practice recommendations in 2016, Hot Dogs UK refer to these guidelines in their article.
A lot of the k9 field medicine (including heat injury prevention and management) comes down from the military who for obvious reasons have a lot of experience in this area.
To quote one working dog Vet...
“We know with Heat Related Illness fatality rates are high, and what you do in the field makes a difference, not how fast you transport to a vet, you eventually have to get them there, but what you do in the field, how fast you cool those dogs down will make or break the life of your Canine, and we're still seeing too many preventable deaths.”
The bottom line is healthy dogs don't die because they were cooled down, they die because they were too hot for too long, and dogs that have been too hot for too long tend to die no matter how you treat them, so then the cooling process often gets the blame (especially when cold water and rapid cooling are involved) when they were going to die anyway because the damage has already been done.
Those that understand this, that work with working dogs in hot environments, that have treated hundreds of these cases in the field, rapidly cool these dogs as fast as possible with whatever they have available, with cold water if they have it, and they save these dogs when they catch it early.
It's probably a luxury if you have multiple cooling methods to choose from so just use what you have to cool the dog as fast as possible while ideally monitoring temperature which is another important point, you can cool too far if you continue to cool past the point the dog's temperature has reached a safe temperature, and because temperature continues to drop for a short time after you stop active cooling measures (plus re**al temp lags behind core temp during rapid temperature changes) it is advised to stop cooling just above normal resting temp, the exact number varies depending on the source but in the range of 103–104°F (39.5–40°C) re**al temp, monitoring is important and doesn't get much attention, the dog should be continually monitored during transport but most pet owners etc. are probably unlikely to have a thermometer (you should have 1 or 2 in your first aid kit) and in that case you have to rely on the person's ability and experience understanding the signs and reading the dog which is not ideal, but in such a case even 10mins of any rapid cooling method before transport will give the dog a better chance. So cooling too far is another reason cooling methods get the blame.
Added to this it is very difficult to change some people's heat philosophy when these outdated ideas have been around a long time, takes a lot of strength of character for some to admit there might be a better way, but it is going in the right direction, albeit slowly, and because of the hard work of some professionals.
It doesn't matter what you learned from your very experienced breeder, other mushers, what you learned from an expert Vet years ago, or what a Vet learned in Vet school 20 or 30 years ago, things move on, if you are not constantly evaluating what you learn, looking to improve, gain new ideas, move forward, keep learning and improving instead of looking in the past then whatever field you are in you will never improve and be any better than you are at this moment.
Those at the top of their game in any field don't get there by doing the same old thing because "that's the way we've always done it" or "that's what I learned years ago", they're constantly learning, looking for new ideas and ways to improve to be the best they can be and improve outcomes, learning from others, if some people didn't have that mindset we would still be in the dark ages, and there are some good people out there to learn from.
There is a lot of debate and argument in this area making it more complicated than it needs to be when the simple message is...
The key to field treatment is simply to cool the dog down as fast as possible using whatever methods are available!
Further information:
MYTH BUSTING – COOLING HOT DOGS with the UK Veterinary research team
https://heatstroke.dog/2023/07/20/myth-busting-cooling-hot-dogs/?fbclid=IwAR07ChOSq-PTfc-DN_B_aePTMzKGq06I7GGuzw3-QBmskg3MipglcSys2Js
ARE YOU READY TO BEAT THE HEAT? COOLING HOT DOGS – MORE MYTH BUSTING
https://heatstroke.dog/2024/04/12/are-you-ready-to-beat-the-heat-cooling-hot-dogs-more-myth-busting/?fbclid=IwZXh0bgNhZW0CMTEAAR1sud0ZKqfM3PF0_xcaQRgdXzmHKfFT5nkuHsZTOq6UYGpjbryDpPmfzbA_aem_RZ7l8lh3RN0PoPvFQMltTA
Royal Veterinary College
https://www.rvc.ac.uk/vetcompass/news/the-rvc-urges-owners-of-hot-dogs-to-cool-first-transport-second?fbclid=IwAR023ZAXQm_1n9FQwo8aVCP2SZdxdmBhXMgwH-e_m3iaX2OHyK0nujbO_Ws
Cooling methods used in dogs with heat-related illness under UK primary veterinary care 2016-2018
https://m.facebook.com/story.php?story_fbid=108153058936611&id=100092257509484
Rethinking Heat Injury in the SOF Multipurpose Canine:
A Critical Review.
Janice L. Baker, DVM; Paul J. Hollier, DVM; Laura Miller; Ward A. Lacy
https://www.researchgate.net/publication/227176693_Rethinking_Heat_Injury_in_the_SOF_Multipurpose_Canine_A_Critical_Review
Heat Injury in Working Dogs Webinar with Dr. Janice Baker
https://m.facebook.com/story.php?story_fbid=108093635609220&id=100092257509484
