title: Dose effect and benefits of glycopyrrolate in the treatment of bradycardia in anesthetized dogs.
abstract: This study evaluated the effectiveness of glycopyrrolate (0.005 or 0.01 mg/kg body weight (BW)) in anesthetized dogs (n = 40) for reversal of bradycardia (< 65 beats/min). Following random intravenous (i.v.) treatment, heart rate was determined at 5 min and, if it was < or = 70 beats/min, the lower dose was repeated. A 2-way analysis of variance considered dose and animal size (< or = 10 kg, > 10 kg) effects (P < 0.05). Glycopyrrolate produced a significant increase in heart rate and infrequent tachycardia (< or = 150 beats/min), which was not dose-related. The size of the dog produced a significant effect on baseline heart rate (higher in small), rate following the first dose (lower in small), and requirement for retreatment (47% in small, 13% in large). In a separate group of anesthetized dogs (n = 20), the blood pressure effect of glycopyrrolate (0.01 mg/kg BW, i.v.) treatment of bradycardia (65-85 beats/min, weight-adjusted) was studied. A significant increase in systolic, diastolic, and mean blood pressure was produced. In conclusion, the effective dose of glycopyrrolate treatment is size-related and produces a beneficial effect on blood pressure.
authors.affiliation: Department of Clinical Studies, Ontario Veterinary College, University of Guelph.
authors.forename: D H
authors.initials: DH
authors.lastname: Dyson
authors.forename: R
authors.initials: R
authors.lastname: James-Davies
mesh_terms: D000759:Adjuvants, Anesthesia / Q000008:administration & dosage* / Q000009:adverse effects; D000704:Analysis of Variance; D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight; D001919:Bradycardia / Q000188:drug therapy*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006024:Glycopyrrolate / Q000008:administration & dosage* / Q000009:adverse effects; D006339:Heart Rate / Q000187:drug effects; D007275:Injections, Intravenous; D007431:Intraoperative Complications / Q000188:drug therapy; D018727:Muscarinic Antagonists / Q000008:administration & dosage* / Q000009:adverse effects; D013610:Tachycardia / Q000139:chemically induced
chemical_list: D000759:Adjuvants, Anesthesia; D018727:Muscarinic Antagonists; D006024:Glycopyrrolate