My final two weeks here were as great as the rest 😊
I saw my favorite case of my twelve weeks here, which was
putting in a temporary tracheostomy
tube. The owner’s complaint was that, following a fall, her horse was
making an odd sound when grazing, and in the past week it had also been
occurring while standing in her stall. The vet performed an endoscopic exam and
saw a swollen but functional right arytenoid and a functional left arytenoid.
There was what appeared to be inflamed lymphoid tissue in the right guttural
pouch, but she had trouble getting in to the left guttural pouch. We sedated
Riley so she wouldn’t shake her head as much, and shortly afterward she began
to make the noise the owner had complained about. We looked at the arytenoids
again, and this time they were collapsed and barley able to abduct. While not a
true emergency, the vet felt it was important to perform the procedure as soon
as possible, as these episodes were leaving the horse with an incredibly small
airway. We scrubbed and blocked the neck before the vet separated the muscles
by cutting on ventral midline and then made a small incision in the trachea,
just large enough to insert the two metal pieces of the trach. As soon as the
tube was in the horse was incredibly perked up. She took several deep breathes
and acted very excited. The vet actually ended up giving her a small amount of
sedation because she kept working herself up over the new noise of her
breathing. It is possible that the horse’s fall damaged a nerve and affecting
arytenoid function. The temporary trach will hopefully allow enough time for
Riley to regain arytenoid function, but if not, a permanent tracheostomy will be necessary. The vet
went back to rescope a little over a week later, and she told me that the
arytenoid function is looking better. It is important to be patient and allow
time and the chance for everything to heal.
Another cool procedure I saw for the first time was a third
eyelid removal. There was growth on the third eyelid that could not be
deciphered between squamous cell carcinoma and eosinophilic keratitis, but
either way the eyelid needed to be removed. We did send the removed tissue to
histology, both for identification and to ensure that clear margins of the
abnormal tissues were achieved. To remove the eyelid, the horse was sedated and
the eye was scrubbed and blocked (the auriculopalpebral and frontal nerve
blocks prevented blinking). Then scissors were used to remove the third eyelid.
The vet cut all the way to the lateral corner, leaving the small bone at the
attachment of the lid. This bone can be removed if needed, but it makes the
procedure more invasive. 5-floururesil, a chemotherapy drug, was injected near
the third eyelid attachment, and the owners received neo-poly-dex ointment to
put in the eye daily to sooth and prevent infection.
A barrel horse that we saw on the farm for repetitive stifle
locking came in to the clinic for an Asheim’s procedure. After surgically prepping the area, Doc made
stab incisions in the medial patellar ligament of each leg, following the
fibers of the tendon. Because the stifles had been previously blistered
multiple times, the area was quite vascular and bled more than normal. With
continued pressure, however, the bleeding stopped after about 10 minutes, and
there was no need to go in and ligate the bleeder.
We went to an emergency call for what the owner thought was
an abscess. The horse has a lump on the side of his neck with a perfectly
circular hole in the center. The vet was suspicious of warbles, but we were
unable to visualize anything inside the hole. He covered the area with vasoline
to cut off any air supply and draw a larvae out if one was inside, but we did
not see anything. He injected the area with a cephalosporin cream.
Most of the foals I saw this summer were either health
checkups or umbilical hernia surgeries, but I did see one that came in for a
conformation check. The foal was quite valgus in his forelimbs, and the owner
opted to do an epiphyseal growth stimulation. This involved laying the foal
down and inserting needles into the growth plates on the lateral side of each
carpus to help stimulate growth on that side of the leg. Although this involved
sedation and surgical prep, the actual procedure was much quicker than I
anticipated. The vet also provided some shoeing recommendations for the
hindlimbs, which she believed could do well with more conservative management
than the forelimbs.
Another case I found really interesting was a horse that had
exercise induced muscle fasciculations and fatigue. A doctor from the clinic
had seen the horse about a year ago for the same issue and they were unable to
determine a cause. After treating with a course of Bute the owner no longer
noticed any twitching. We lunged the horse about 2 times each direction, during
which the horse almost tripped once. After the lunging muscle twitching was
evident in multiple locations and the horse seemed very weak. The vet described
it as looking like HYPP, but the owner said that there was no Impressive breeding
(the stallion associated with HYPP) and that both parents tested double
negative (heterozygous HYPP horses can still show sign). Additionally, the
horse did not look like a typical HYPP horse and it would also be unusual for
the disease to not manifest until the horse was 17 years old. Conversely, PSSM
(polysaccharide storage myopathy) generally shows signs around mid teens. We
drew blood to test for this as well as a chemistry, which would show high muscle
values, like CK, in a PSSM horse. Blood was also drawn for an ACTH (to rule out
Cushings because of the horses age) and a Vit E test. Last year when the vet came
out the Vitamin E was low-normal, so it was possible it could have dropped more,
causing issues. Unfortunately the results did not come in before I left, but I’ll
make sure to edit this post if I hear from the doctor soon about the results 😊
On one of my last days we had to wait for a Farrier at one
call and the doctor decided to quiz me on anesthesia protocols, since I had
seen so many sedations over the course of the summer. For a basic hock
injection, the doctors generally start with a 1.25cc dormosedan and 0.25cc
xylazine injection. Torb (butorphanol) is useful for when it’s important that
the horse to keep its hind legs on the ground (ie: if it’s known to kick), but
it’s important to realize that Torb will often make them lean forward and can
cause them to jerk sporadically. For dentals the doctor will, depending on the
horses size, start with about 0.8cc dorm, with 1.0cc being the upper limit. If
the horse is young and steady she will top off with more dorm, which has a ceiling
effect. If the horse is older or not as steady she will top off with torb.
Often sheath cleanings are combined with dentals, but if just doing a sheath
cleaning, the doctor uses a combination with Acepromazine because it will cause
the horse to drop. Xylazine/Ace is a good combination for a well behaved horse,
but sometimes Dorm/Ace is used. Torb/Ace is used when the horse is likely to
kick to help keep his hind legs on the ground.
I learned a ton this summer and will miss the people I got
to meet and work with. I really
enjoyed my time with Cleveland Equine!
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