Perioperative changes in cardiac troponin I concentrations in dogs

This study determines the influence of general anesthesia on serum cardiac troponin I (cTnI) concentrations in dogs. All dogs showed no abnormalities on clinical and echocardiographic examination. Venous blood samples were drawn within 12 h of induction and 12 h after discontinuation of anesthesia. Each dog was premedicated with methadone i.v. and induced with diazepam i.v. and propofol i.v.. Anesthesia was maintained using isoflurane in oxygen in combination with a continuous rate infusion of fentanyl. The cTnI concentrations were measured using a third generation chemiluminescent microparticle immunoassay with a detection limit of 0.01 ng/mL (below this level '<0.01 ng/mL'). Ten dogs (55%) had a post-anesthetic increase of cTnI concentration relative to their pre-anesthetic cTnI concentration, whereas a decrease was observed in two dogs (11%). This study shows that cTnI can increase in healthy dogs undergoing general anesthesia.