Pulmonary function in horses with recurrent airway obstruction after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively.

OBJECTIVE: To determine changes in clinical signs of disease and response to pulmonary function testing in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. ANIMALS: 6 horses with inducible and reversible heaves. PROCEDURE: Episodes of heaves were induced by exposure (challenge) to moldy hay and straw for 7 days. Horses were assigned to treatment groups (aerosolized beclomethasone dipropionate, parenterally administered dexamethasone, aerosolized propellant [control]), and respiratory frequency and subjective assessment of respiratory effect were determined twice daily. Maximal change in pleural pressure (delta-Pplmax), pulmonary resistance (RL), and dynamic compliance (Cdyn) was determined on days 0, 7, 10, 14, and 21. RESULTS: The RL and delta Pplmax were increased, and Cdyn was decreased in all horses in response to natural challenge. Beclomethasone reduced RL on day 10, reduced delta Pplmax on days 14 and 21 and increased Cdyn on day 14. Dexamethasone reduced RL and delta Pplmax on days 10, 14, and 21 and increased Cdyn on days 10 and 14. Respiratory effort (subjective assessment) improved after 2 and 3 days of beclomethasone and dexamethasone administration but rebounded to pretreatment values 1 and 3 days after discontinuation of drugs. CONCLUSIONS: Pulmonary function testing responses and clinical signs of airway obstruction were improved by administration of beclomethasone. The magnitude of response to aerosolized beclomethasone generally was less marked than the response to parenterally administered dexamethasone. Higher or more frequent dosing of aerosolized beclomethasone may be necessary to achieve the anti-inflammatory response to parenterally administered dexamethasone.

Incarceration of the small colon through a rent in the gastrosplenic ligament in a pony.

A 10-year-old castrated male pony was examined for intermittent signs of abdominal pain of 3 days' duration. An incarceration of the small colon through a rent in the gastrosplenic ligament was found. Resection and end-to-end anastomosis were performed on the affected portion of the small colon. The pony recovered and returned to its previous degree of activity. Incarceration of the small intestine and large colon through rents in the gastrosplenic ligament are documented, although involvement of the small intestine is more common. To the best of our knowledge, incarceration of the small colon has not been reported. Although a rare event, incarceration of the small colon in the gastrosplenic ligament should be considered in the differential diagnosis list for horses with intermittent signs of abdominal pain.

Comparison of medical and surgical treatment for impaction of the small colon in horses: 84 cases (1986-1996).

OBJECTIVE: To characterize clinical findings and compare effects of treatment and outcome for horses treated medically or surgically for impaction of the small colon. DESIGN: Retrospective study. ANIMALS: 84 horses with impaction of the small colon. PROCEDURE: Medical records were reviewed for history, physical examination findings, laboratory values, treatment, response to treatment, complications, out-come, and necropsy findings. RESULTS: 47 horses were treated medically and 37 horses were treated surgically. Significant differences between groups were not identified for duration of clinical signs, physical examination findings, or laboratory values. Horses treated surgically were hospitalized longer than horses treated medically. Complications recorded during hospitalization included diarrhea, jugular thrombophlebitis, recurrent colic, fever, and laminitis. Salmonella organisms were isolated from 20 horses. Horses treated surgically were more likely to have signs of moderate abdominal pain, gross abdominal distention, and positive results for culture of Salmonella spp than horses treated medically. Follow-up information was available for 27 horses treated medically and 23 horses treated surgically. Twenty-four (72%) and 21 (75%) of the horses, respectively, survived and were being used for their intended purpose at least 1 year after treatment. CLINICAL IMPLICATIONS: Colitis may be a predisposing factor for impaction of the small colon in horses. Prognosis for horses treated surgically or medically is fair.