title: Evaluation of a combination of xylazine, ketamine, and halothane for anesthesia in llamas.
abstract: Anesthesia induced by use of a combination of xylazine, ketamine, and halothane, under conditions of spontaneous and mechanically controlled ventilation, was evaluated in 5 llamas positioned in dorsal recumbency. Using chronically implanted catheters, systemic arterial blood pressure, pulmonary arterial pressure, right atrial pressure, heart rate and rhythm, cardiac output, blood pH and gas tensions, body temperature, and respiratory rate were measured before anesthesia induction (baseline), throughout the anesthetic period, and for 1 hour into the recovery period. During anesthesia, llamas undergoing spontaneous ventilation developed hypercapnia and respiratory acidosis. Cardiovascular function was decreased during both types of ventilation. The combination of xylazine, ketamine, and halothane in various doses and 2 ventilation procedures (spontaneous and controlled) provided a reliable method for general anesthesia in llamas, but marked cardiovascular depression developed during anesthesia maintenance with halothane. Spontaneous ventilation resulted in potentially clinically important respiratory acidosis.
authors.affiliation: Department of Medicine, School of Veterinary Medicine, University of California, Davis 95616.
authors.forename: D
authors.initials: D
authors.lastname: Gavier
authors.forename: M D
authors.initials: MD
authors.lastname: Kittleson
authors.forename: M E
authors.initials: ME
authors.lastname: Fowler
authors.forename: L E
authors.initials: LE
authors.lastname: Johnson
authors.forename: G
authors.initials: G
authors.lastname: Hall
authors.forename: D
authors.initials: D
authors.lastname: Nearenberg
mesh_terms: D000768:Anesthesia, General / Q000662:veterinary*; D000818:Animals; D002319:Cardiovascular System / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D006221:Halothane / Q000008:administration & dosage* / Q000494:pharmacology; D007649:Ketamine / Q000008:administration & dosage* / Q000494:pharmacology; D012137:Respiratory System / Q000187:drug effects; D012418:Ruminants / Q000502:physiology*; D013843:Thiazines / Q000008:administration & dosage*; D014991:Xylazine / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D004338:Drug Combinations; D013843:Thiazines; D014991:Xylazine; D007649:Ketamine; D006221:Halothane