RESUMO
OBJECTIVE: To report serum cardiac troponin I (cTnI) and C-reactive protein (CRP) concentrations in dogs anesthetized for elective surgery using two anesthetic protocols. STUDY DESIGN: Prospective, randomized clinical study. ANIMALS: Twenty client-owned dogs presenting for elective ovariohysterectomy or castration. METHODS: The dogs were randomized into two groups. All dogs were premedicated with glycopyrrolate (0.011 mg kg(-1)) and hydromorphone (0.1 mg kg(-1)) i.m. approximately 30 minutes prior to induction of anesthesia. Anesthesia in dogs in group 1 was induced with propofol (6 mg kg(-1)) i.v. to effect and in dogs in group 2 with diazepam (0.2 mg kg(-1)) i.v. followed by etomidate (2 mg kg(-1)) i.v. to effect. For maintenance of anesthesia, group 1 received sevoflurane (adjustable vaporizer setting 0.5-4%) and group 2 received a combination of fentanyl (0.8 microg kg(-1) minute(-1)) and midazolam (8.0 microg kg(-1) minute(-1)) i.v. plus sevoflurane (adjustable vaporizer setting 0.5-4%) to maintain anesthesia. Serum cTnI and CRP concentrations were measured at baseline and 6, 18, and 24 hours post-anesthetic induction. Biochemical analysis was performed at baseline. Lactate was obtained at baseline and 6 hours post-anesthetic induction. Heart rate and mean arterial blood pressure were measured intra-operatively. RESULTS: Baseline serum cTnI and CRP concentrations were comparable between groups. A significant difference in serum cTnI or CRP concentrations was not detected post-operatively between groups at any time point. Serum CRP concentrations were significantly increased post-anesthetic induction in both groups, which was attributed to surgical trauma. CONCLUSIONS AND CLINICAL RELEVANCE: There was no significant difference in serum cTnI and CRP concentrations between anesthetic protocols. Further investigation in a larger number of dogs is necessary to confirm the current findings.