Intra-abdominal bleeding in a horse : not always of traumatic origin

A nine-year-old warmblood mare was presented with clinical signs of mild colic and fever. On percutaneous ultrasound of the abdomen, a mass was identified on the left side of the abdomen between the spleen and the stomach. During examination the following day, intra-abdominal blood was observed. On rectal examination, a mass was palpated in the pelvis. The presumptive diagnosis of hematoma with intra-abdominal bleeding was made. On consecutive ultrasounds and radiographs, the mass evolved in shape and other masses were identified in the liver and the lungs. No change was noticed in the pelvic mass. Cytology and histology of a tru-cut liver biopsy revealed abnormal, most likely neoplastic cells, whereas cytology of the abdominal and thoracic fluid did not reveal any neoplastic cells. Due to the presence of several rapidly growing masses, a neoplastic process was most likely. Because of the malignant character of the disease and the persistence of the clinical signs, euthanasia was suggested but refused by the owner. Supportive treatment was instituted. Initially, the general condition remained stable, after which the horse suddenly collapsed and died. Post-mortem examination revealed a primary neoplasm located in the pelvic cavity, as well as multiple disseminated masses within several tissues. The mass found in the liver had ruptured with loss of probably 50 liters hemorrhagic fluid within the abdominal cavity. Based on gross pathology, cytological and histological findings, a hemangiosarcoma was suspected. This diagnosis was confirmed using immunohistochemistry for von Willebrand factor. In this case report, the importance of differentiating hematoma from hemangiosarcoma in the horse is highlighted

Phenylephrine-induced epistaxis in a six-year-old Quarter horse with nephrosplenic entrapment

Left dorsal displacement of the large colon is a common cause of colic in horses. Treatment consists of surgery, rolling the horse under general anesthesia or intravenous administration of phenylephrine. Treatment with phenylephrine, an alpha 1-adrenergic drug, is often associated with sweating and trembling. Especially in horses of more than 15 years old, fatal hemorrhage may occur due to hemothorax or hemoperitoneum. Therefore, phenylephrine treatment is generally not given in horses over 15 years of age. In this report, severe epistaxis in a six-year-old Quarter horse is described after intravenous administration of 22.5 mu g/kg BW phenylephrine, and it is highlighted that hemorrhage may also occur in younger horses

Association between flax bedding and ileal impactions in horses : retrospective analysis of 2337 gastrointestinal cases (2008-2017)

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The risk of flax versus straw bedding on ileal impaction in colic horses : retrospective analysis of 2336 cases (2008-2017)

While mature coastal bermudagrass hay is strongly associated with ileal impaction in theSoutheastern United States, stabling on flax bedding has anecdotally been associated with thiscondition in Europe. The aim of this retrospective study was to investigate the association betweenileal impaction and the use of flax shives compared to straw as bedding in horses withcolic. Medical records of 2336 referral cases evaluated for abdominal pain between January 2008and May 2017 at the Department of Large Animal Internal Medicine, Ghent University werereviewed. Diagnosis, date of admission, age, breed, gender, body weight and stable bedding wererecorded. Conditional logistic regression analysis was used to assess the association between ilealimpaction and each individual variable. Odds ratios (OR) and 95% confidence intervals (CI)were determined. Predictors with a value of P < 0.2 were included in a multivariable Cox regressionmodel and Wald’s test was used to assess parameter estimate significance. Further, the associationbetween survival to discharge and type of bedding or type of treatment (medical versussurgical) was analyzed for horses with ileal impactions. The proportion of colic cases stabled onflax bedding at home was 11.3%. The overall prevalence of ileal impaction was 4.2%. In the flaxgroup, the prevalence of ileal impaction was 9.4% as opposed to 3.6% within the straw group.The OR of 2.8 (95% CI 1.7-4.7; P < 0.001) in the multivariable logistic regression model indicatedthat horses stabled on flax shives were approximately three times more likely to have ileal impactionsthan horses stabled on straw. There was no significant association found between ilealimpaction and the period of admission, age, gender or body weight in a multivariable logisticregression model. The odds for having ileal impaction is approximately six times (OR 6.3; 95%CI 2.4-16.4; P < 0.001) higher in draft horses than in warmbloods in the multivariable logisticregression model. No significant association was found between survival to discharge and type ofbedding or treatment. These results suggest that horses with colic that were housed on flax beddingare more likely to present ileal impactions than horses housed on straw

Pheochromocytoma in a horse with polymorphic ventricular tachycardia

A twenty-four-year-old mare, which had been examined seven years earlier for mitral valve regurgitation and mild left sided cardiomegaly, was presented with tachycardia, profuse sweating and muscle fasciculations. Blood examination revealed an increased packed cell volume, meta-bolic acidosis, hypocalcemia, hyperglycemia and increased cardiac troponin I concentration. ECG revealed ventricular premature beats and monomorphic ventricular tachycardia followed by polymorphic ventricular tachycardia with R-on-T phenomenon. The horse was treated immediately with hypertonic solution followed by isotonic solution and calcium, but the general condition deteriorated within forty-five minutes after arrival. The horse was euthanized due to poor prognosis. On necropsy, a pheochromocytoma of the left adrenal gland was found. Although this horse had undergone a cardiovascular examination seven and one year prior to the onset of the clinical signs, no indications for a neoplastic process or symptoms of a pheochromocytoma were found at that time. Early diagnosis of pheochromocytoma is based on catecholamine mediated cardiovascular effects, blood examination, blood pressure measurement, rectal palpation and rectal ultrasound of the adrenal gland. Based on a retrospective analysis of echocardiographic images and measurements, no predisposing factors were found. In this article, the importance of including pheochromocytoma as a differential diagnosis is highlighted, especially in older horses with acute polymorphic ventricular tachycardia, sweating, muscle tremors and signs of acute abdominal pain

Effect of sotalol on heart rate, QT interval, and atrial fibrillation cycle length in horses with atrial fibrillation

Background: Based on its pharmacokinetic profile and electrophysiological effects in healthy horses, sotalol potentially could be used as a long-term PO antiarrhythmic drug in horses. Objectives: To evaluate the effect of sotalol on heart rate (HR), QT interval, atrial fibrillatory rate, and success of cardioversion in horses with naturally occurring chronic atrial fibrillation (AF). Animals: Twenty-eight horses referred for transvenous electrical cardioversion of AF were treated with 2 mg/kg sotalol PO q12h for 3 days before cardioversion, and 13 horses underwent the same protocol without sotalol administration. Methods: Retrospective study. Before and after sotalol or no treatment, the HR was measured at rest and during an exercise test. The QT interval and atrial fibrillation cycle length (AFCL) were measured at rest using tissue Doppler velocity imaging. Results: In the control group, no significant differences were found between the 2 examinations. In the sotalol group, the HR at rest and during exercise was significantly lower after sotalol treatment, whereas the QT interval and AFCL measured by tissue Doppler increased significantly. Cardioversion to sinus rhythm was achieved in 25/28 horses in the sotalol group and all horses in the control group, but the median number of shocks and energy at cardioversion were significantly lower in the sotalol group. Conclusions and Clinical Importance: In horses with AF, sotalol administration results in class III antiarrhythmic effects and -blocking activity, with moderate HR reduction during exercise