Echocardiographic effects of dexmedetomidine-ketamine in chinchillas ( Chinchilla lanigera)

Alpha₂-agonist anesthetic combinations are often used in rodent anesthesia but no information about their effects on cardiac function in chinchillas exists. The purpose of this study was to utilize echocardiography to evaluate the cardiovascular effects of dexmedetomidine-ketamine anesthesia in chinchillas. Echocardiographic examinations were performed in eight adult chinchillas under manual restraint and following dexmedetomidine (0.015 mg/kg) and ketamine (4 mg/kg) administration. Dexmedetomidine-ketamine anesthesia resulted in a significantly decreased heart rate, fractional shortening, cardiac output, and flow velocity across the aortic and pulmonic valves, and significantly increased left ventricular internal diameter in systole. The observed changes in echocardiographic parameters are similar to those previously reported in chinchillas anesthetized with isoflurane.