Comparison of the Effects of Diazepam, Acepromazine and Xylazine as Preanesthetic Agents in Preventing Cardiac Arrhythmias in Sheep Under General Anesthesia with Ketamine

Abstract Cardiac arrhythmias are an important potential complication of general anesthesia. This dissertation investigated and compared the effects of the preanesthetic agents diazepam, acepromazine, and xylazine on the occurrence of cardiac arrhythmias in sheep anesthetized with ketamine. The study used electrocardiographic monitoring to evaluate cardiac responses during anesthesia and examined the susceptibility of the animals to epinephrine-induced ventricular arrhythmias. The preanesthetic agents were compared under controlled experimental conditions, with particular attention to the dose of epinephrine required to provoke clinically significant ventricular ectopic activity. The results indicated that the three preanesthetic drugs did not provide a uniform or reliable protective effect against epinephrine-induced cardiac arrhythmias during ketamine anesthesia. The findings emphasize the importance of careful cardiovascular monitoring when ketamine anesthesia is used in sheep, particularly when sympathetic stimulation or catecholamine administration may occur. Bibliographic information Author: Hojjatollah HaselpourDegree: Doctor of Veterinary Medicine (DVM)Institution: School of Veterinary Medicine, Shiraz University, Shiraz, IranAcademic year: 1376–1377 (1997–1998)Dissertation No.: 684Supervisor: Dr. Ali Rezakhani This record contains an English-language public summary of the original Persian DVM dissertation. It is intended to make this historical veterinary research easier to discover through scholarly search engines and research repositories. Keywords Sheep; Ketamine; Diazepam; Acepromazine; Xylazine; Preanesthetic medication; Cardiac arrhythmia; Electrocardiography; Epinephrine; Veterinary anesthesia