First of all, mare is currently at my vet's clinic and we're working on possible courses of treatment, but thought I'd see if anyone here has experience that could be helpful... sorry in advance this is long.
I have a 25yo mare who delivered one foal about 8 years ago. She was a sporthorse her whole career but now retired. From my many years and many $ spent trying to breed her, I've known for some time that she has some cervical defects. For one thing, it's extremely tightly closed, but there's also a wonky right turn in there. This made it difficult to breed her because she always retained fluid. For the past several years, she's periodically expelled fluid either every or every other heat cycle - we're talking a fairly large amount of fluid expelled, typically overnight while in her stall, to the point that you'd basically strip the stall the next day. She would be uncomfortable the evening she passed the fluid - acting like going into labor, having contractions to expel the fluid, etc., but would be back to normal the next morning like nothing ever happened. I basically focused on keeping her comfortable during these episodes but otherwise in a "wait and see" mode.
Unfortunately, we've now passed "wait and see" ... she had an episode earlier this week where I think she was trying to expel the fluid but couldn't, and started acting colicky (big red flag was that she didn't eat her dinner, which for this mare means the end of the world has arrived). Trip to the emergency clinic overnight where the emergency vet felt an impaction and set her up with IV fluids, etc. Upon exam the next morning, still felt an impaction but she had passed manure regularly during the night, so they ultrasounded and discovered a large amount of fluid in her uterus.
At that point, I moved her to my regular vet's clinic. He's an experienced repro vet and has seen this mare for years. He's been able to manipulate her cervix enough to insert a catheter, and over the course of the past few days, we have drained 8-10 gallons of fluid (fairly thick, pinkish pus) from this poor girl I feel just awful knowing now how uncomfortable she must have been ... I'd thought that this summer had been particularly hard on her and have been sad that this was the first year where I really noticed her aging. Now in retrospect I'm thinking this is what has slowed her down the past few months, not to mention what a tough old mare she is to have dealt with this for a while.
Now that all the fluid has drained, my vet is doing a course of uterine lavages and has a sample of the fluid out for culture to determine if there's an infection we can treat, but has already warned that even if that is the case, clearing that up probably won't fully resolve the fluid issues. So, anyone have experience with this and how to handle going forward? Obviously the "magic bullet" would be to spay her, but my vet and I both feel that such major surgery at 25 years old could just be replacing one set of issues with another. We've talked about possibly just setting up a standing appointment for every month or two to bring her in to drain and flush, but depending on how quickly the fluid re-accumulates this may or may not be that effective. My vet is consulting with A&M and CSU about the possibility of somehow creating a permanent opening in the cervix - has anyone dealt with that before? Any other thoughts? This mare is worth her weight in gold for all her years packing me around jump courses, and I want to do whatever I can to keep her happy and healthy as long as possible!!
Last edited by eniskerry; Aug. 30, 2011 at 09:57 AM.
Sorry, I missed that. I know with dogs they don't even attempt to treat it because the infection itself is life threatening. The adage is don't let the sun set on a pyo, meaning spay them today. I understand why that isn't an option in this case but I am afraid that limits your options. I am jingling like crazy!
Oophorectomy in the equine is typically referred to as an ovariectomy. It can be performed as a colpotomy, where incisions are made at 10 and 2 o'clock on each side of the cervix in the vagina and the ovaries are "caught" and removed through those openings. There is more risk associated with this procedure than an ovariectomy performed through a flank incision (the principal increased risks being accidentally trapping a loop of bowel, and infection), but the financial costs are less.
An ovariectomy in this situation may or may not produce a positive result though. In order to understand the logistics, we need to explore the hormonal cycle of the mare. I'll not get too detailed, but before I start, I will point out that use of Regumate (or any other progestin) in this situation would be contra-indicated. The reason for this is that progestins suppress uterine immune response and close the cervix, so you would probably end up with an even worse pyometra if there is an infectious agent involved (and mares prone to infectious agents in this manner are typically re-infecting themselves due to poor reproductive confirmation issues and/or uterine clearance failure).
OK... on to the hormones...
Progesterone is secreted by the CL that forms on the ovary following ovulation. A couple of it's main functions are to close the cervix and suppress uterine immune response (hence not wanting to use Regumate in this situation). So... if we remove the ovaries, no progesterone. So far so good... BUT, when the mare comes into estrus (before we ovariectomize her obviously!!), the developing follicle secretes estrogen. Now estrogen is a very good hormone, as it not only encourages relaxation of the cervix (good in this situation), but also increases blood flow to the uterus, and this in turn increases the degree of immune response present (important if one is about to put a load of gunk in there along with semen in a breeding situation!!). Obviously, increased immune response would be beneficial in a mare facing periodic pyometra. The problem here is no ovaries = no increased estrogen = no increased uterine immune response.
So, ovariectomy may not be a solution.
On the flip side, many mares live quite happily with pyometra. Obviously if it gets to the point where distension of the uterus is threatening to cause a rupture, it's time to do something about it, but in cases up to that point, systemic illness is not usually associated with it, unlike some other species such as dogs (if you've got a dog with pyometra, not treating it is going to result in the death of the dog). In many cases therefore, where pyometra is detected but the mare is not ever going to be bred, the uterus may simply be monitored to ensure excessive distension does not occur, and the mare left alone and not treated in any way until - or rather only if - the pyometra starts causing a potential threat.
Thanks all for the suggestions. Unfortunately Regumate is not an option for the reasons Jos mentioned. And bad news is, this doesn't look like something we can manage with monthly treatments - vet drained another 20 liters of fluid this morning after just two days Culture results came back and unfortunately there was pseudomonas. So, now we're treating for that but vet isn't too optimistic we can get it fully cleared up and not have it just come right back. He's consulted with Texas A&M, and we have a referral appointment up there for Monday. From his initial discussions with them, our options seem to be limited to either a hysterectomy (not a great option due to her age), or creating a permanent opening in her cervix. That can be done standing without general anesthesia, and ideally should allow any fluid to drain regularly. They'll evaluate her on Monday to see if she's a candidate - crossing my fingers that she is and that this will work!
Update 8/30 - Just wanted to share an update in case anyone else has to deal with this type of issue. I'm cautiously optimistic with good news! A little over a month ago we ended up taking Annabel up to the vet school at A&M, and after about a week of treatment to get the infection cleaned up, they proceeded with a "partial cervical resection." Essentially, they cut out a wedge from her cervix to create a permanent opening to give fluid somewhere to drain. Although not a common procedure by any means, it was "relatively" low-risk with no general anesthesia required, so a much better option for her given her age than a full hystorectemy. They kept her another few days after the procedure to massage the area with steriod cream to try to minimize scarring to keep the resected area from closing back over as much as possible, then sent her home. She's been home about 3 weeks now and was getting daily shots of oxy to try to work on the uterine tone. We took her back yesterday for her follow-up appointment - surgeon said he's not thrilled with the results, but "content." Basically at this point, if she's happy, we'll all be happy even if it's not quite the results they were hoping for. The cervix didn't stay quite as open as they'd have liked, but there definitely is an opening now. There was some fluid in the horns of the uterus, which we expected just given the effects of gravity - but when they drained the fluid, we were only talking 2 liters now instead of the 20 we were draining before. Also did a Betadine flush, and vet is optimistic there is no residual infection, although we're waiting on culture results to confirm. We're stopping the oxy injections and they'll check her again in 2 months. I suspect we'll ultimately end up having my local vet check her every 3-4 months here to flush if needed and make sure we don't end up back where we started, but that's very manageable.
Most importantly, Annabel is feeling tons better and much more back to her old self. She's 25 years old, and I'd really been feeling down that this summer seemed to be taking a much harder toll on her than any before - I thought it was a sign of her age catching up to her. But she's definitely getting back to her usual self ... which on the one hand makes me feel awful knowing that she was in so much discomfort because of this, but at least now we've hopefully fixed it and she'll have many more years ahead of her! Not to mention that after the procedure when she stopped retaining so much fluid, she looked like she'd dropped about 300 pounds. It was really shocking and I felt so bad - she looked like she'd been starved! Although I don't think she's complaining since now she gets a full scoop of feed and alfalfa twice a day - this mare lives to eat
Still crossing my fingers that everything continues to operate smoothly, but it looks like for now we've made big progress.