TitleComparison of bronchodilators in alleviating clinical signs in horses with chronic obstructive pulmonary disease.
Publication TypeJournal Article
Year of Publication1989
AuthorsPearson, EG, Riebold, TW
JournalJournal of the American Veterinary Medical Association
Volume194
Issue9
Pagination1287-91
Date Published1989 May 1
KeywordsTrachea
Abstract

A representative of each of 3 types of bronchodilators was given iv to horses with clinical signs of chronic obstructive pulmonary disease. We used atropine (0.01 mg/kg of body weight) as an anticholinergic, isoproterenol HCl as a beta-adrenergic, and aminophylline, the soluble salt of theophylline, as a methylxanthine. Response to these drugs was evaluated by measuring maximal change in intrathoracic pressures (delta Ppl) and observing clinical signs. Atropine caused a significant (P less than 0.01) reduction in delta Ppl, compared with that caused by aminophylline. Atropine caused the delta Ppl to decrease an average of 83 +/- 15% toward normal. Clinical improvement was noticed in 87% of the cases. Maximal changes in pleural pressures were reduced by an average of 21 +/- 14 mm of Hg, with 27% returning completely to normal. Isoproterenol helped 77% of horses clinically, and caused delta Ppl to decrease an average of 68 +/- 31% toward normal. The average reduction in delta Ppl was 16 +/- 10 mm of Hg. Aminophylline helped alleviate clinical signs of 50% of the horses and caused delta Ppl to decrease an average of 41 +/- 36% toward normal. The average reduction in delta Ppl was 10 +/- 11 mm of Hg.