Weeks 6-9 at Littleton Equine Medical Center

Hello again from Littleton!

I hope everyone is having as great of a summer as I am!  I have been learning so much here as always and have been getting to spend some time with family in Boulder doing fun outdoor activities.  There have been a lot of neat cases here lately, and I’m excited to share some of what I’ve been learning here with you.

Things have been going pretty much as usual around here lately with a lot of colic and lameness work.  There have been a few horses that have come in with septic joints or that have been suspected to have them, so I have been able to watch and help with several regional limb perfusions.  Regional limb perfusions are great because they utilize a tourniquet proximally and infusion of a concentration-dependent antibiotic such as amikacin distal to the tourniquet to achieve a high concentration of antibiotic in the area of concern.  This is also favorable because you can avoid some potential complications that could result from systemic use of antibiotics.

One interesting case that came in was a 4-month old foal that was referred in because it had had seizures over the few days prior.  The owner started noticing the seizures occurring after it ran into a fence and was treated for head lacerations.  Luckily for me, I was working in the ICU the day that the foal was admitted so I was able to follow its case and observe it very closely for a few days.  Initially, the foal was somewhat obtunded mentally and was suspected to be blind, but upon ophthalmic exam was seen to have pupillary light reflexes and a dazzle response.  Its menace responses were absent, but those are a learned behavior so they may not have been developed yet in this foal.  Radiographs of the head were unremarkable, and the owner declined to have an MRI performed.

The foal also had some concerning lacerations over two of its fetlock joints, so it was sedated and Dr. Hill distended the joints with sterile saline to see if the lacerations communicated with the joints.  One had a small communication and was flushed and infused with amikacin, but the other joint was intact.  The foal did not have any seizures over the next few days, but over the weekend started having them daily.  Dr. Mullen made a great point by suggesting that either the foal could have had seizures because of the head trauma from running into the fence, or could have run into the fence because it was having a seizure.  She was more inclined to believe that due to the fact that two weeks after the traumatic event that the foal was still having seizures, that it was more likely to have idiopathic juvenile epilepsy rather than being simply trauma-induced.  Initially, the foal was treated with an IV fluid cocktail that included DMSO to help with any potential edema in the brain and later was medicated with phenobarbital and gabapentin to control the seizures.  Once the dose was adjusted, the owner elected to take the foal home.

Speaking of neurologic cases, there was a horse that came in that the owners said appeared to have acutely developed neurologic signs when ambulating.  We had a slow afternoon in the ICU, so I was able to observe Dr. Hill and Dr. Kurkowski work up its case.  When the mare arrived, she was hypermetric in all of her limbs and really hesitated to set down her feet when moving forward.  When she was moved in circles, she didn’t appear to be particularly neurologic—she wasn’t circumducting her hind limbs (swinging them outward when moving) too much and didn’t seem to have any proprioceptive deficits (she appeared to know where her feet were).  On physical exam, the vets noted that she had increased digital pulses in all four limbs, and increased digital pulses indicate pain in those distal limbs that have the stronger pulses.  She also had a positive response to hoof testers in all four limbs, particularly over the toe region.  Due to the quick onset of her signs and the clear indications of foot pain, she was most likely laminitic.  To further assess whether her odd movement was due to pain instead of being neurologic in origin, the vets then did an abaxial sesamoid nerve block with carbocaine in both front feet to block any pain that might be originating from the foot, as would be expected with laminitis.  The difference in her movement was very dramatic, and she moved almost normally after the nerve blocks.  Radiographs were then taken and did show early indications of some rotation, so the mare was treated for laminitis with ice boots and anti-inflammatories.  She did well, and was sent home a few days ago.

As always with veterinary medicine, not all cases have a happy ending.  Fortunately, the vast majority of the colic cases (and all cases in general) that I have seen here have been successfully treated, but some horses that require surgery to correct their colic unfortunately do not have that option due to owner constraints.  Other times, horses are not able to arrive until it is too late and some part of their GI tract has ruptured, which is beyond repair.  Last night, two emergency colic cases arrived late in the evening.  One was a horse in its early 30’s that had been seen in the field and was suspected to have a strangulating lipoma but needed further evaluation to be sure.  This horse did not have a surgical option.  Ultrasonography revealed some even distention of the small intestine but good motility and passage of digesta rather than it “settling out”, or rather seeing the digesta sitting in the bottom on the intestine and not filling it and moving through.  An abdominocentesis was performed (in other words, a belly tap) and lactate was evaluated, which was not significantly elevated.  These were good findings for the horse, because a high lactate (should normally be below 2) indicates poor perfusion (lack of blood supply), and a very high lactate suggests that there is likely dead bowel somewhere in the abdomen.  So, what was expected to be a bad case ended up going pretty well, and the mare was instead treated with IV fluids and monitored closely because she did have a number of signs of dehydration.

Sadly, the other colic that came in was not expected to be as severe as it turned out to be, and the lactate on that horse’s abdominocentesis was 17.  Combined with the other findings on her workup, the owner elected to euthanize her.  I observed and helped take part in the necropsy, which helps the vets and the owner to know definitively what went wrong.  This is helpful, as sometimes a horse’s cause of death is preventable, otherwise can help assure an owner that they made the correct decision, and is a good learning tool for the veterinarians involved as well.  This horse did in fact have a strangulating lipoma (a growth of fat that can tighten down over a loop of intestine, block food from passing through it, and cut off its blood supply) and as a result had several feet of very dead ileum.  The owner definitely made the correct decision for the circumstances involved in this case.  Other cases have been highly rewarding, such as a horse that survived colic surgery that had a 720 degree torsion at the base of her cecum, and two year old that did not have a surgical option and survived medical management for a suspected right dorsal displacement.  Although such cases are highly rewarding and others are very sad, I am so appreciative that as veterinarians we are able to alleviate suffering in either situation.

I wish I could share all of the other neat things I’ve been seeing here lately but seriously, I’d be writing a novel.  I saw an OCD the size of a golf ball removed from a hock, a horse that was referred in to have a vaginal cyst removed but here was found on pre-surgical exam to be an intact hymen, a “sidewinder” horse (a neurologic horse that moves sideways everywhere it goes), and a mare that fractured her coffin bone while playing in the pasture.  This weekend they’re having an open house here, and I’m very excited for my family to see where I’ve been working.  Also, they’re having pony rides and face painting so my 2 and 5-year old nieces will be happy campers. J  Although I love vet school, I am truly not excited for my time to be dwindling down to my final two weeks here.  I’ll save the sappy goodbyes for next week, and I’ll give you all one more post after my final week.

-Calli

Equine Athlete: Week 12

Hello again!  After a day of rest once returning from Youth Nationals we hit the ground running on Wednesday to get back to our home-base patients.  We spent the remainder of the week around Michigan and Indiana doing prep for the upcoming Canadian Nationals.  Although technically considered a 'normal' week, we did see some very interesting cases around the area.

Image I. Nail found in horses heel.

This week Dr. Hill, Dr. Smith, and I had full days every day.  Our week started off with a bang at a small private farm in Michigan.  We were called out to do a few lameness exams and treatments, which all went well.  Then, as we were cleaning up they asked if we could take a quick look at a 2 year old colt that had suddenly been found lame.  We  lunged the horse and pinpointed the area of concern.  As soon as we picked up the foot to do a flexion test we found the problem.  A nail was protruding from the horses heel (Image I).  The location of the nail was concerning as its angle of entry, from our external perspective, suggested possible involvement of the deep digital flexor tendon or navicular bursa. We took radiographs of the foot to make sure that no key structures were involved.  Luckily, the nail was 'U' shaped and only involved the edge of the heel bulb.  So, we simply removed the nail at the proper angle, soaked the foot, cleaned and dressed the area, and were off to our next stop after a very interesting morning.

Later in the week we were examining a Warmblood gelding that we have seen multiple times throughout the summer.  He was originally being rehabilitated from a suspensory injury and has been deemed sound in that leg.  Unfortunately, he has been having trouble moving forward and bending.  We watched him move and noticed that he wasn't tracking forward as well with his left front leg.  After an examination and blocking of the leg up to the level of the shoulder, we knew it had to be something higher up.  Dr. Hill went through a chiropractic exam and noticed that he was reluctant to bend his neck.  That tipped us off and so we radiographed the region of the that was most sore.  Immediately the problem was evident, arthritis of his 5th and 6th cervical vertebrae (Image II-IV).  Once the vertebrae become arthritic you can only manage the condition, but cannot cure it.  So we opted to take an aggressive approach and attempt to slow down the bone growth using OsPhos (bisphosphnate), and alleviate the pain by injecting the cervical facets.  The horses case will be followed over time to assess the level of arthritis in that region.

        

Image II. Normal vertebrae

Image III. Arthritic vertebrae

Image IV. Oblique view of the arthritic vertebrae

Image V. Clubbed foot on a 4 month old filly

Continuing on our adventurous week we were called to examine a four month old filly with a clubbed foot.  I have seen quite a few clubbed feet but have yet to see one this sever, and in this young of a horse.  The client wanted to radiograph the foot in order to determine whether or not she would be a candidate for corrective surgery (Image V).  Clubbed feet can have a variety of causes including genetic predisposition, improper farrier care, or an injury causing excessive flexion (to name a few).  In foals of this age the major problem is often excessive flexion of the deep digital flexor tendon (DDFT).  Tightening of the DDFT causes the toe to rotate downwards and, without correction, clubbing of the foot.  The heel will grow too long and the front of the foot will become steep and dished.  If caught early there are many options for correction.  Corrective bandaging, farrier work to lower the heal and lengthen the toe, and surgery are the most common.  In this severe of a case surgery was deemed the best option. Surgery for a clubbed foot involves severing the inferior check ligament in order to release tension along the back of the leg.  The procedure is officially termed an inferior check ligament (ICL) desmotomy.  By ligating the ICL you essentially 'release' the DDFT and allow it to relax.  This should lower the heel and improve the clubbed foot.  The client elected to send the filly to surgery.  I am awaiting news on whether or not it was a success.

This week was filled with a lot of interesting cases. Too many to share in this "quick" blog post.  I am grateful for all that I have learned this summer thus far.  By this point I am well able to follow the cases and understand what is happening.  I am excited to head up to Canada next week and see what is in store!

Equine Athlete: Weeks 10-11

What more can I say then 'wow'?  The two weeks we spent at Arabian Youth Nationals were exciting, exhausting, and educational.  I have never experienced that scale of horse show environment.  Youth Nationals represents the culmination of a year of hard work put in by trainers, youth riders, and their mounts.  Unlike the other shows I have been to this summer, Youth had a much more exciting, even electric, feeling surrounding it.  Partially due to the fact that it is a strictly youth exhibition, and partially due to the sheer scale of the event.  Everywhere you looked there were more horses, more decorations, more excited youth riders charged with enthusiasm.  It was captivating.

What struck me the most was the amount of pride that this industry has for its breed.  The Arabian horse is rooted in history, and the Arabian Horse Association (AHA) doesn't fail to recognize that.  Costume classes pay homage to the breeds heritage in the Middle East.  While memorial classes recognize those persons who have made an impact on the industry itself.  It is encouraging, in the turbulent environment we live in, to see so many young people sharing an enthusiasm for the breed.  The Arabian industry took a hit when the economy turned but, with so much interest from a younger generation, numbers are coming back up and hopefully will stay that way for years to come.

From our position as show vet, we got a unique perspective of the show.  We arrived on Tuesday with the show set to start that Friday and run to the following Saturday.  Only a fraction of the horses had arrived yet, but we were already hitting the ground running.  Equine Athlete brought quite an impressive team with them.   Five veterinarians, two from the Texas branch and three from the Central Michigan group.  Including our newest edition, Dr. Bailey Smith.  To assist, there were five technicians/vet student assistants, two from Texas and three from Central Michigan.  All in all we had a team of ten taking on Youth Nationals.

Once we arrived the work seemed to never stop.  The first battle we had to face was respiratory distress induced by the long travel and high temperatures in Oklahoma; commonly referred to as shipping fever.  A lot of our clients had traveled more than 15 hours in order to reach Oklahoma.  Long rides like that put a lot of stress on horses, not to mention the huge temperature change from the Midwest.  High heat and humidity, combined with the position horses are in when in trailers creates a perfect storm for respiratory pathogens.  Naturally, horses eat with their heads down.  This allows dust and debris that might be in the hay to be cleared from the horses airway by gravity.  When trailering, horses stand for long periods with their heads tied up, preventing the clearing of microorganisms and debris.  After a stressful trip or the excitement of being in a new place, many horses presented with respiratory symptoms.  Luckily, these horses get the best care possible.  As soon as they come off the trailer farms take their temperature and look them over for any scrapes or soreness.  If anything is out of sorts, we are immediately called over to assess and treat.

Image 1. Infected region of lung

Shipping fever presents in a relatively recognizable fashion.  Horses will have an elevated temperature, increased respiration rate (often coupled with a labored breathing pattern), 'harshness' upon auscultation of the lung fields, and lethargy (head droop, reluctance to move, refusal of feed).  Our exam includes a complete physical, paying close attention to auscultation of the the lungs and gastrointestinal tract (in case the stress has induced colic).  Next we will ultrasound the lungs and look for evidence of consolidation/infection (Image 1).  Some major pathologies that we will see are "comet" like streaks indicating infected regions of lung, or darker, fluid filled regions indicating a possible abscess.  We also ran a stable side test for SAA or serum amyloid A.  SAA is an indicator of the severity of the respiratory disease process.  SAA is a bio-marker for the inflammatory process, which takes place when the lungs become infected.  More traditionally, fibrinogen levels are the standard for measurement of the inflammatory response, yet they take longer to elevate and are not as convenient in these acute cases.  Levels of SAA are measured for many pathologies resulting in inflammation; including laminitis, cellulitis, joint swelling, etc.  We monitor these levels every few days and use them to help paint a picture of the horses recovery.  Levels below 50 ug/mL (according to StableLab guidelines) are considered normal, although it takes a while for the levels to drop completely.  As long as they trend downwards consistently the doctors consider that an indicator of healing. If the horses are dehydrated we will place a catheter and run them fluids to help get them on the road to recovery.  We then place them on a round of antibiotics if the case warrants them.  Depending on the presentation and severity horses were mostly placed on a combination of Gentimicin and Sulfamethoxazole (SMZ), or Naxcel (ceftiofur sodium).  We rechecked the horses twice a day and continued the antibiotics for at least three-five days until they showed significant improvement.  Thankfully all of our respiratory cases resolved before the actual start of the show.

The rest of Youth went by in a whirlwind of treatments, a few colics, a handful of lacerations, and not much sleep.  It was thrilling to see the event proceed and the teams at each stable working together to make their riders dreams come true.  I enjoyed watching horses that I now recognized from the different farms go in and show at their best thanks, in small part, to our hard work.  The common consensus was that this turned out to be one of the most competitive years to date; between the quality of horses in the ring, and skill presented by the youth riders.  This industry is so very different from anything I have seen before.  The quality of animals, kindness and enthusiasm of the people, and sheer passion show by all involved.  I won't soon forget the feeling of being at Youth, or my fortune in being part of a team of practitioners that helped make it happen.  We now set our sights on Canadian Nationals but will be riding the high of Youth for some time.

The final class at Youth Nationals!

Equine Athlete: Week 9

Image 1. Radiograph depicting slight rotation of the coffin bone

Although the horse show is currently taking over most of my time, I would like to share a quick case study before discussing the amazing, yet insane, experience that is Youth Nationals.

We have been managing a few laminitis cases this summer and I wanted to share some of what I have learned.  Laminitis, by definition, is a painful inflammatory condition within the hoof.  Laminitis occurs when the sensitive laminae become inflamed.  It is the job of the laminae to connect the hoof wall to the distal phalanx, or coffin bone.  Failure of this attachment, or even acute inflammation of the laminae, results in extreme pain as the coffin bone essentially pulls away from the hoof wall.  Chronic laminitis can result in significant separation, and eventual rotation, of the coffin bone due to the downward pressure of the horses weight (Image 1).  The 'dropping' of the coffin bone and eventual failure of the bond is called founder.  If left untreated, laminitis will eventually result in extreme rotation of the coffin bone and penetration of the sole.  It is difficult to manage severe laminitis and is therefore imperative that proper preventative measures are taken in high risk horses.

Laminitis can be caused by multiple metabolic and physical triggers.  Physical causes can include excessive weight bearing on a limb due to contralateral injury or systemic infection causing inflammation.  Acute laminitis can be induced when horses or ponies gorge themselves on lush grass or high starch grains.  The sugars from these feeds trigger the release of inflammatory mediators from the hindgut resulting in inflammation in sensitive structures, such as the laminae.  Metabolic predispositions are a lot less straightforward.  The two common culprits are Pars Pituitary Intermedia Dysfunction (PPID or Cushing's disease) and Equine Metabolic Syndrome (EMS).  PPID is caused by failure of proper communication between the pituitary gland and hypothalamaus that results in increased release of cortisol/steroid production from the adrenal gland.  Increased steroid levels can cause a reflexive constriction of blood vessels in the hoof.  This limits circulation and can compromise the supporting structures within the hoof.  Increased levels of steroids can also result in insulin resistance.  It is believed that this resistance can inhibit cells in the hoof from taking up glucose, lose energy and "stretch" as a result.  This insulin based dilemma is at the heart of laminitis caused by EMS.  Although many mechanisms are effected by hyperinsulinemia, there are a few at the root of the problem.  First, decreased blood flow to the hoof caused by activation of vasoconstriction mediators in the blood vessels.  Secondly, resistance to insulin decreases glucose in hoof cells as with PPID.  Lastly, the high insulin levels are believed to activate insulinlike growth factor (IGF) receptors on cells in the laminae.  Cells are activated to grow and change, essentially weakening the support mechanism within the hoof causing the "pulling away" of the coffin bone.  More research is being done into the exact underlying mechanisms causing laminitis to develop in horses with PPID or EMS.

Managing horses with a predisposition is a full time challenge.  It is imperative to make sure these horses have a high forage, low concentrate diet and limit grazing on lush pastures.  Maintaining a healthy weight can reduce stress on hoof structures versus overweight horses.  Hoof care is also a key factor in managing pre-laminitic and laminitic horses.  Proper hoof balance is extremely important, make sure your farrier is aware of the condition.  Periodic radiographs can give insight into how the foot is doing and help with early detection of any changes.

If laminitis occurs treatment should be quick and aggressive.  Keeping the horse on soft surfaces helps them be more comfortable (think deeply bedded, padded stall or even a flooded area of ground outside).  You can also place them in SoftRides or another padded hoof support if they will wear one calmly.  Many people will help aid in decreasing inflammation by icing the feet periodically throughout the day.  Then you can place the horse on anti-inflammatories such as phenylbutazone (Bute) or flunixin meglumine (Banamine).  One treatment that I learned about this summer was the administration of pentoxyfylline, an anti-inflammatory and vasodilator.  The goal in treatment is to get the inflammation decreased as quickly as possible and then wait and see.

Laminitis is not an easy management challenge for the owner, veterinarian, or farrier.  But, it can be done if caught early enough.  The disease itself has been around a long time, but treatment options are always evolving.  That is all I have to say on laminitis for now, stay tuned for the exciting update on Arabian Youth Nationals in Oklahoma City, OK.  Thank you for following along on my adventures!

Weeks 3-5 at Littleton Equine Medical Center

Hello again from Littleton!

It’s been very busy around here lately, as summer and the horse show season is in full swing!  I have still been spending most of my days working in the ICU, which has generally been pretty full.  Most of the horses admitted to the ICU are for various colics, but there have also been a few mares and foals, major laceration survivors, and an interesting cardiac case.  I was able to watch when Dr. Mullen, the internist, did an echocardiogram of a horse’s heart and saw an abnormal mass.  The horse had been admitted with a heart rate of 170 bpm (normal is around 28-44 bpm) with a lot of premature ventricular contractions.  Bilaterally, this horse also had thrombosed jugular veins, so had to be catheterized via the cephalic vein.  He was treated with heparin IV, oral aspirin, Plavix, and lidocaine IV and was monitored with a Holter monitor.  His jugular veins were also observed via ultrasonography to assess blood flow and the extent of the thrombi formation.  I am interested to keep learning more about his case partly because I could really use a good review of cardiology!

I have also gotten to see a lot of colic cases come through so have learned a lot lately about the different causes of colic, modalities for diagnosing them, and their subsequent treatment options.  I learned that a nephrosplenic entrapment can be treated with phenylephrine HCl (to contract the spleen) and trotting for 5-10 minutes to try to release the entrapped colon from the space between the spleen and kidney.  Also, you need to use caution when treating with phenylephrine, especially in older horses and at higher doses, because it can potentially rupture the spleen.  You can also anesthetize the horse and physically roll it around (I haven’t seen that one yet but that would be neat-o) to try to free the entrapment as well.

On Mondays, I spend the day in the field with one of the veterinarians.  Sometimes, the day is mostly filled with farm calls and other days many of the cases are at the clinic.  Last week, I spent the day doing repro work with Dr. Dietz.  We spent the first part of the day checking mares and it was a really good review of horse reproduction.  I spent two years in grad school learning the finer aspects of sheep reproduction and estrus synchronization, and this was a great refresher of how mares are opposite of sheep and cows in many, many ways.  Even mares’ ovaries are inside out.  One mare that we saw was suspected to have a uterine infection, so Dr. Dietz took two swabs of the uterus; one for cytology and one to be cultured.  She then lavaged the uterus with sterile saline and treated the mare with enrofloxacin (a broad spectrum antibiotic), dexamethasone, and oxytocin.  When we went on some farm calls to check local mares and on one particular mare, Dr. Dietz saw that she had an ovulatory follicle and lavaged her then checked again afterward and saw that she happened to ovulate while being flushed.  It was really neat to see what a freshly ovulated follicle/corpus hemorrhagicum looks like.

I know it’s really common, but I got to see a Caslick’s procedure performed for the first time that day too.  Dr. Dietz did the closure with a Ford interlocking pattern, which is less complicated than I imagined it would be.  Caslick’s procedures are useful for mares that have poor vulvar conformation or are prone to pneumovagina, both conditions of which predispose them to infections of their reproductive tract.  Later in the day, we went to a farm for a colic emergency, and Dr. Dietz quizzed me on colic types and treatments along the way.  Once there, she diagnosed a small impaction via rectal exam, and we passed a nasogastric tube to administer a bolus of fluids and electrolytes as well as some mineral oil.  The mare ended up recovering well overnight.

One emergency farm call that I went with Dr. Harbourd on involved an older pony that was down and could not rise.  I learned a useful recipe for a “Lazarus cocktail” that can be administered IV and is comprised of butorphanol, banamine, calcium gluconate, and dextrose with fluids to help a downed horse.  This cocktail provides pain relief, fluids (if they’ve been down for a while, they’re likely somewhat dehydrated), and easily utilizable energy.  Fortunately with the help of Dr. Lori and some butorphanol, we were able to get the pony up before administering it.  More useful information that I learned on that farm trip was that you should do your best to move the front end of the horse or pony away from the wall or corner of the stall, because they need a good amount of space in front of them to get up.

As always, the Monday morning meetings have been full of great information.  Lately, we have learned about field management of colics, colic diagnostics, and how to minimize the risk of veterinary misadventures (as well as how to resolve them if they do occur).  This morning’s talk in particular was extremely useful.  One of my major concerns about being a new graduate within a few years is how to recognize and resolve complications as they arise.  This morning, Dr. Toppin taught us how to recognize and treat an anaphylactic reaction, how to minimize the risk of inadvertently doing an intra-carotid injection, and how to treat vaccine reactions.  I feel better about being able to recognize when a complication has arisen, and about how to go about treating it one day if it occurs.

Last week, I spent Monday working with Dr. Toll doing farm calls.  First, she repaired an uncomplicated laceration below the stifle, trimmed proud flesh from a heel bulb injury on the same horse, and applied chlorhexidine ointment as a treatment to help prevent the reoccurrence of proud flesh (excess granulation tissue).  At another farm, I scrubbed the site for IRAP injection at the lateral femorotibial joint and learned that the landmarks are the lateral collateral ligaments, lateral patellar ligament, and tibial plateau ventrally.  IRAP is useful for treating osteoarthritis and general joint inflammation by stimulating the horse’s own immune cells to produce anti-inflammatory mediators.  She also floated an older pony’s teeth and I learned how to open a horse’s mouth more easily without getting my hand gnawed off.  At the end of the day, we saw a horse that had an allergic reaction to who knows what in its stall.  Its eyes were nearly swollen shut and its muzzle was so inflamed that it was squeezing out past its halter.  It also had hives over the rest of its body.  She treated it with an IV injection of dexamethasone and oral hydroxyzine (an antihistamine).

Also, I got to see a DDFT tenotomy done on a horse with chronic laminitis.  This procedure is a salvage procedure, and the purpose is to reduce the backward pull that the DDFT exerts on the coffin bone.  It was performed as a standing procedure, and the vets also worked with the horse’s farrier to see that it was outfitted with heartbar shoes and the dorsal hoof wall was trimmed back to improve the breakover in the horse’s foot.

Anyhow, I’ve learned a ton so far and am excited to keep seeing and helping with more here.  I’m sad that my time here is officially halfway over but hope you’re all having a great summer as well!

-Calli

Equine Athlete: Weeks 7-8

After two hectic weeks at the Regional shows we all took a day to recover over the 4th of July holiday.  Then it was back to work catching up on local patients and beginning preparation for Youth Nationals.  There have been many opportunities to see and learn new things over the past few weeks.  The doctors have been fantastic teachers and are always willing to talk me through the procedures that they are doing.  We have gotten to see some fun things over the past two weeks.

Regional limb perfusion

It all kicked off with a regional limb perfusion.  I have heard of the procedure but was excited to be part of one.  Regional limb perfusion (RLP) is often used in large animals to deliver medication or antibiotics to specific areas versus systemic administration.  More recently RLP has been used to deliver stem cells to areas with tendon or ligament injuries.  The Quarter Horse gelding was perfused with mesenchymal stem cells in order to help in the healing of a chronic injury to the suspensory branches.  Mesenchymal stem cells have been shown to increase the rate of healing in tendon and ligament injuries.  It is believed that the properties of stem cells draw mediators and cells to the injured area to promote healing.  In order to perform the RLP Dr. Hill placed a tourniquet distal to the carpus and perfused via the lateral palmar digital vein.  We then left the tourniquet on for 30 minutes under a wrap over the injection site.  When the treatment was complete we wrapped the leg with a pressure wrap and administered some banamine.  Hopefully this procedure can offer our patient some relief.

Dr. Hill performing an ultrasound exam

At one of our next stops we got to follow up with a horse that had damaged its suspensory ligament.  Before this summer I had very little experience with ultrasonography beyond reproductive imaging.  Dr. Hill has been a fantastic instructor and has kindly walked me through his exams.  This particular case involved a gelding that became acutely lame at a horse show earlier this season.  He had a history of suspensory soreness but always responded to shockwave therapy, icing, and other management practices.  He was given time off prior to the show season in order to rest the area and prevent major injury.  Unfortunately, a bad step off of the trailer had the farm calling Dr. Hill.  Upon exam we were able to pinpoint the area of acute soreness in the lateral branch of the suspensory ligament.  Ultrasound examination revealed significant edema within the branch.  The farm was instructed to rest the horse in its stall for 30 days with daily icing.  When we were next out at the farm we performed a follow-up exam.  It was great to see the side-by side comparison of the injury.  Healing was easily visible between the images and the horse was cleared for two weeks of hand-walking and a slow return to work.  Before we left we shock-waved the area to kick-start further healing.  We will be back to re-examine the horse and hope to see even further correction.

The level of care, from farm to show ring, that is offered at Equine Athlete has provided me a full circle view of this kind of equine medicine.  It is a unique opportunity to be able to follow cases throughout my internship and learn, not only about diagnostics, but treatment and long term management of various ailments.  I am very fortunate to have been given this opportunity and look forward to my final month with the Equine Athlete team.

Equine Athlete: Weeks 5-6

Hello from Lexington, Kentucky and the Region 14 Championships.  We have spent the last two weeks away at regional shows.  Last week Dr. Hill and I were in Springfield, Ohio for Region 13.  This week the whole group is together in Lexington for Region 14, a much larger show.  The days are full of various activities and no two days are the same.  We are the show vet here at 14 and therefore we see everything from our traditional lameness case, to colic cases and unexpected show injuries.  This week has also given me the opportunity to become more familiar with treatments that get done at shows versus at home.

One of my main duties has been to perform the laser treatments on different horses.  I have now become very familiar with the equipment and treatment options.  Typically, I have been treating sore backs, fetlocks and feet.  This week though, I have had the opportunity to treat some wounds.  One of my favorite laser cases involved a horse who rubbed his tail on the trailer ride to Lexington.  When we first examined the damage we couldn't believe he had managed to scrape himself up so much.  By the time we looked at it there seemed to be a possibly bacterial component and a lot of hair loss.  We cleaned the area and prescribed sulfadiazine, or SSD, cream (an antibiotic and protectant).  The horse was scheduled to show later that week, and therefore we needed to help speed up the healing process.  He was put on my laser schedule and I got to work.  Every morning I would arrive and asses the wound, clean it with soap and water, and then laser the area.  I am pleased to announce that after a few days of proper care and lasering, the area is looking much better.  Note the decrease in redness and lack of irritation after only one day of treatment.

Image 1. Day 1

Image 2. Day 2

The shows finished up without any major cases of travel or show related illness.  I have been told not to count on such luck as the show season progresses and the weather heats up.  Our next big show is Arabian Youth Nationals in Oklahoma at the end of July.  The weather is going to be brutal, and therefore cases of shipping fever and colic will most likely be numerous.  So I am sure I will have time to broach that subject when we get to Youth.  For now I will sign off from the road as we head to our next big farm prep.  This week and next will be spent preparing everyone for Youth and catching up on our smaller farms more locally.  We have already seen some interesting cases that I am looking forward to sharing with you all soon.  So stay tuned and have a great week!

Weeks 1-2 at Littleton Equine Medical Center

I can’t believe how quickly the past few weeks (and the majority of the summer) have blown by so quickly!  I got a later start out here than I would have liked because I was in Washington DC doing the Smith-Kilborne project, which was also a great and insightful experience.  The first few weeks out here have involved a lot of ICU training as well as learning who the doctors, techs, and assistants are (there are 21 veterinarians including interns as well as techs and assistants for each), where everything is located, and learning the general routine here.  The majority of the work that I have done so far has been in the ICU, although my schedule is changing now to include days of observing and assisting with surgery as well as working with veterinarians here in the field.  One thing that I love is that every Monday morning, there is a staff meeting with case presentations and discussions of relevant current topics. 

The first few weeks in the ICU had some slow days, so I was able to go watch procedures and workups in the exam rooms in the main part of the clinic.  I feel like such a nerd being so excited about seeing diseases and conditions that we learned about in vet school, but I have gotten to see some really interesting cases lately!  My third day here, I came in partway through a procedure where they were doing a local block on a horse’s croup/hip area and oddly, started seeing bubbles coming out of the horse’s skin as the needle was removed.  As I heard the attending vets discussing the information about the presentation and history of the horse, such as that it had received an intramuscular injection in that location a few days prior, I realized that this horse had clostridial myositis and they were preparing to do surgical fenestrations in the skin at that location.

As a refresher for what clostridial myositis is…clostridial bacteria (commonly Clostridium perfringens type A, which is a Gram negative anaerobe) can either be inoculated or lie dormant in muscle tissue as spores.  They can convert to their vegetative, or active, form if there is sufficient trauma or irritation to their surrounding environment of skeletal muscle.  When that happens, they often release gas in the local tissues (so you may feel crepitus upon palpation) and can release some potent exotoxins that can potentially cause a systemic toxemia in the horse.  Although cases of clostridial myositis are frequently associated with intramuscular Banamine injections, they can also be caused by other intramuscular injections or even simple tissue trauma.

Fortunately, clostridial myositis is relatively uncommon.  Surgical fenestrations are necessary to perform because the bacteria must be exposed to oxygen in order to destroy them and combat the infection.  Prior to making incisions, the attending vets used ultrasonography to evaluate the extent of the infection so that they could determine where the cuts would need to be placed.  The underlying tissues were also debrided and the horse was later put in the ICU to be monitored and recover with IV potassium penicillin, supportive care, and daily wound cleaning and debridement.

The following day was another light day in the ICU so I came up to the clinic later in the day to observe and help with more cases.  A horse came in that had a high fever and was acting “off.”  He had been turned out with other horses, and had been bitten on the shoulder about 5 days prior to coming into the clinic.  The majority of his right side was uneven looking and he had ventral edema down his right side.  Again, crepitus could be palpated dorsally on this horse and after the shoulder wound was evaluated with cytology, clostridial myositis was again diagnosed.  The infection was more extensive in this horse and spanned from his shoulder to the end of his abdomen from about ¾ of the way up dorsally down to his ventrum.  Again, he was evaluated via ultrasound and was treated with surgical fenestrations, lavage, potassium penicillin, and also gentimicin because his white blood cell count was lower.  A major concern with treating horses with clostridial myositis is the potential complication of laminitis as a result of the systemic toxemia, so these horses were also placed in ice boots and Easy Rides (as well as having received general supportive care) and fortunately had no major complications.

I have also gotten to help with lameness and prepurchase exams both at the clinic and on farm calls and have had the opportunity to observe some interesting surgeries.  The most interesting one so far has been a carpal arthroscopy, not because they are very uncommon, but because it was the first time that I have been able to see an equine surgery that wasn’t performed as a standing procedure.  The arthroscopy was successful, and a large osteochondral fragment was removed from the horse’s carpus that had been lodged between the distal radius and the radiocarpal bone.  I learned how to recognize fibrillated cartilage and full thickness erosions, and Dr. Devine then finished the procedure by performing microfracture on the full thickness erosions to help stimulate fibrocartilage growth.

There have also been many, many colicky horses that have come in.  Two horses were also treated that came in with a rectal tear, but unfortunately both had to be euthanized despite great effort to save them.  That lead to a very useful discussion during the staff meeting on diagnosing the presence and extent of rectal tears and complications, a review of treatment methods, and good practices to help reduce the risk of causing one.

Overall, my first two weeks have been a blast and I am excited to continue learning from everyone here!  Everyone has been very kind and helpful, and I feel like I’m finally starting to get the hang of things around the clinic.  There has also been a fair bit of turnover lately because the old interns just finished up their year here and the four new interns have recently arrived.  Also, new externs arrive every two weeks, so that has been a good chance to meet and mingle with other vet students from other schools.  I have learned a tremendous amount in my first few weeks already and am looking forward to continuing to learn and contribute here for the rest of the summer!

-Calli