Comparison of bronchodilators in alleviating clinical signs in horses with chronic obstructive pulmonary disease.
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.
Pearson
E G
EG
College of Veterinary Medicine, Veterinary Teaching Hospital, Oregon State University, Corvallis 97331-4802.
Riebold
T W
TW
D000628:Aminophylline / Q000627:therapeutic use; D000818:Animals; D001285:Atropine / Q000627:therapeutic use; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D001999:Bronchoscopy / Q000662:veterinary; D006734:Horse Diseases / Q000188:drug therapy*; D006736:Horses; D007545:Isoproterenol / Q000627:therapeutic use; D008173:Lung Diseases, Obstructive / Q000188:drug therapy / Q000662:veterinary*; D010994:Pleura / Q000503:physiopathology; D011312:Pressure; D014132:Trachea / Q000473:pathology
D001993:Bronchodilator Agents; D000628:Aminophylline; D001285:Atropine; D007545:Isoproterenol