Actual vets: hyperkalemia in horse with HYPP

Interestingly, a recent article in the literature recommends the following for horses in respiratory distress due to an acute HYPP episode. No mention at all of insulin.

“Acute distress cases should also be managed by stabilizing the muscle membrane with slow administration of 23% calcium gluconate diluted in 0.9% NaCl (0.2–0.4 mL/kg) and reducing extracellular potassium levels with intravenously (IV) 5% dextrose solution alone (4–6 mL/kg) or in combination with 8.4% sodium bicarbonate (0.5–1.0 mEq/kg or 0.5–1.0 mL/kg).”


Why would it be given that way?

My point is that it wouldn’t/couldn’t. The OP was the one who suggested otherwise.


I was questioning the IV part of your answer. My husband is diabetic and so was my old dog and insulin is not given IV.

Insulin is not given IV to diabetics, but it IS given IV in severe cases of human hyperkalemia - i.e. the same scenario as an HYPP attack in horses. The OP was suggesting that horses in the middle of a HYPP attack be treated the same as a hyperkalemic human patient. The rest of us are pointing out the many reasons why that is not advised.


Insulin is frequently given IV in humans in a hyperkalemia situation.


Thank you. I didn’t know that. Reason why I was asking .

All cleared up @Montanas_Girl.

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Figured that.
Reason why I answered. :slightly_smiling_face:


Insulin can also be given IV to humans in diabetic ketoacidosis who require an insulin drip.


Likewise in small animal medicine.


I THINK the owner did not know but the horse was a quarter horse and they are more prone?

From UC Davis Genetics LAb:

This genetic defect has been identified in descendants of the American Quarter Horse sire Impressive. The original genetic defect causing HYPP was a natural mutation that occurred as part of the evolutionary process. The majority of such mutations, which are constantly occurring, are not compatible with survival. However, the genetic mutation causing HYPP produced a functional, yet altered, sodium ion channel. This gene mutation is not a product of inbreeding. The gene mutation causing HYPP inadvertently became widespread when breeders sought to produce horses with heavy musculature. To date, confirmed cases of HYPP have been restricted to descendants of this horse.


It’s a QH disease, which means it’s in the Quarter Horse and Paint breeds, and since they are outcrossed to a LOT of other breeds, any horse of stock horse breeding has the potential

And, it’s ONLY if the are a descendant of Impressive. It’s likely it was actually his dam who was the originator, but her line, outside of Impressive, died off fairly quickly, leaving him to propagate the disease.


Call me ignorant, but there are still HYPP horses out there?! I was under the impression that they were actively trying to eradicate this by being more selective with breeding… Oh… Never mind. :joy:


H/H horses haven’t been allowed in AQHA for a good while now, but yes, n/H is still allowed. I heard that was stopping at some point in the future but I’m not sure if that’s actually true or if it is, what year.

APHA is behind the times.

And, there are outlier registries who happily accept H/H QHs.

Until all registries deny registration for all HYPP horses, it will continue.

It was lots of years back (12 years I believe) so maybe it has changed now, but last time I read a rule book update for ApHC (Appaloosa) they even went so far as to adding whatever the medication that many of these horses are on to the allowed show medication list instead of making some rule to discourage people from breeding horse with HYPP.

But that article and this topic is a great example of - you don’t know what you don’t know.

We (general) go thru life assuming most people know this stuff, but it appears the person in the article had no idea about HYPP and it looks like some people here do not know about it either.

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Isn’t there also the problem that a Quarter Horse that has HYPP may just be sold on as a grade horse?

A buyer who doesn’t know about HYPP, or who knows but doesn’t know that they’re buying a Quarter Horse, might think they’ve got a stunning horse and a great deal, at least until something bad happens.


I should hope that any person buying a grade horse that looks like a QH would have testing be part of their PPE.


IMHO that article is indicative is sticking your head in the sand and ignoring the issue, in favor of supporting the money that comes in from registering ?/H horses :angry: But, I don’t know the wording. However, it was VERY well known what HYPP was 12 years ago, so I don’t see how they can claim ignorance.

Yep, and it happens over and over, not just QHs by breeding, but QH/APHA/ApHC crosses

Stop allowing any positive horse to be registered, and people will at least lessen breeding those horses because they won’t want the 50% chance of an unregisterable horse. Of course, some will still stick their heads in the sand and bet the odds, and sell the nH horses as “grade”.

And while eventually there wouldn’t be registered horses with HYPP, there will be for a LONG time, HH and nH horses who are breeding backyard grade mutts.

Nice thought, but when you don’t know what you don’t know… Lots of those cheaper grade horses sell to “backyard homes” who simply want a nice occasional trail horse and don’t know nearly enough. They don’t even know that HYPP exists, much less what it is. I see them on a regular basis in some FB groups where someone posts about their horse’s episode, someone suggests HYPP status, and the poster goes “huh? what’s that?”

I mean just this past week I ran into a “long time Connemara breeder” who didn’t know what an IgG test was :angry: And when I explained it to her, she claimed we were all being scammed into spending money because ya know, if a foal drinks enough colostrum he’s fine.

That is so sad.

Back to the HYPP thing. I have a friend, a too-trusting friend, who bought a QH mare a few years ago. She took the seller’s word and bought the horse without looking at papers (because they were between owners or some other clearly made up nonsense) and because she really only does trail riding, like many people that do only trail riding, no PPE either so no blood draw. When papers eventually showed up she was a little annoyed to say the least that the mare was positive. :face_with_symbols_over_mouth:

Lovely mare. As various friends met the lovely mare they almost always asked if she would breed her. Friend has an ARE YOU OUT OF YOUR FRIGGIN’ MIND look that can’t be mistaken, “What part of HYPP positive did you not hear me say?” They’d would almost to a one tell her that the chances were only 50/50 that the foal would have HYPP. :crazy_face:

Thankfully, that’s one mare that won’t be contributing to the continuation of AQHA’s bullshit handling of the situation, but only because she accidentally got into the right hands :confused:

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