Seric Concentration of Troponin I and Electrocardiographic Tracing in Dogs Submitted to Long-Term Sedation during 24 Hours

ABSTRACT

Background: General anesthetics and sedatives are commonly used for long-term sedation in veterinary medicine; however, they can lead to cardiac suppression. Cardiac troponin I is a biomarker used to detect myocardial pathology, monitor treatment, and assess outcomes in veterinary patients. The aim of this study was to evaluate the serum concentration of troponin I (cTnI), the electrocardiographic (ECG) tracing, and the ventricular stroke work index in dogs undergoing two long-term sedation protocols over 24 h.Materials, Methods & Results: Twelve healthy mongrel dogs with an average weight of 13.2 ± 2.3 Kg were admitted for this study. Twenty-four h before the experiment began (M-24), venous blood samples were collected for chemiluminescent cTnI evaluation and ECG data were obtained, specifically heart rate (HR); P, PR, QRS and T wave duration; P, R, T wave amplitude; and ST segment depression. On the day of the experiment, the animals were anaesthetized with propofol and isoflurane, and instrumented. After instrumentation, right and left ventricular stroke work index (RVSWI and LVSWI respectively) and intrapulmonary shunt (Qs/Qt) were performed as baseline parameters. The isoflurane was then discontinued and the animals randomly allocated to two groups (n = 6 each) Midazolam and fentanyl group (GMF), in which the animals received a bolus and continuous rate infusion (CRI)