A Taste of Internal Medicine

            This week brought a couple of cases that fall into the “things you don’t see every day” category. Dr. Hill and I were called out to an emergency late one afternoon for a horse that was lethargic and had spiked a fever. Anticipating some kind of infectious- probably respiratory or GI- cause, we greatly surprised by what we found. Upon arrival, the horse’s head was hanging and swollen to about twice its normal size and he had visibly strong jugular pulses as well as ventral edema. The physical exam revealed an obvious heart murmur, thoracic auscultation of pleural effusion, and an elevated temperature.  Since no one had suspected that a horse with a fever would turn out to be a horse with congestive heart failure, Dr. Hill tried to break the news to the owners slowly. She gave them enough Lasix and Ace make the horse comfortable for a couple days while we ran some bloodwork and the owners came to terms with the news. When his bloodwork returned with a hematocrit of 5% (severely anemic) and evidence of liver distress, the euthanasia was scheduled.

            The second strange case had a happier resolution. This gelding had been diagnosed with renal tubular acidosis by Ohio State four years ago and came back into the clinic for care and monitoring while the owners were out of town. In this case of renal tubular acidosis, the proximal tubules of the kidney are damaged and unable to resorb bicarbonate from the urine back into the bloodstream. The large amounts of bicarbonate lost through urination makes the horse acidotic while the urine becomes inappropriately alkaline. To manage the acidosis, a permanent esophagostomy tube was placed and the owner administers a slurry of baking soda and water through the tube four times a day. She uses a pH strip on his urine and saliva to crudely monitor the bicarbonate levels and adjust the routine as needed.  While he was here, I took over the baking soda treatments and ran a chemistry profile every day to monitor the bicarbonate level. Despite his condition, the horse has been doing well these past four years and is competing in dressage at the Prix St George Level.