Cardiovascular pathology possibly associated with ketamine/xylazine anesthesia in Dutch belted rabbits.

摘要

After myocardial necrosis and fibrosis was observed in 5 rabbits which had been anaesthetized a variable number of times, the potential relationship of these lesions and anaesthesia was evaluated in 35 other rabbits. Anaesthesia was induced by i.m.administration of ketamine and xylazine followed by infusion of lactated Ringer's solution also containing ketamine and xylazine. Nine rabbits (group A) were subjected to multiple anaesthesia and were evaluated by echocardiography, thoracic radiography,electrocardiography, determination of serum coronavirus titre, vitamin E concentration, and complete PM examination. Before a single acute procedure followed by PM examination, 11 rabbits (group B) were evaluated by echocardiography only. 10 rabbits (group C) examined PM had never been anaesthetized. Five rabbits (group D) had intermediate anaesthesia exposure history and were evaluated by echocardiography only. Myocardial fibrosis was scored semi-quantitatively on a scale of 0 to 4. Canine coronavirustest results were negative; hypovitaminosis E was evident, and fibrosis scores were significantly increased in group A, compared with group B or group C rabbits. Aetiological differentials included alpha2-agonist-mediated coronary vasoconstriction with associated myocardial hypoperfusion, hypovitaminosis E and free radical injury.