Abstract
Objective—To study the hemodynamic effects of marbofloxacin (MBF) in isoflurane-anesthetized dogs.
Animals—6 healthy 8-month-old Beagles.
Procedure—Anesthesia was induced with sodium thiopental and maintained with isoflurane. Cardiovascular variables were monitored throughout anesthesia. Marbofloxacin was administered by an IV bolus at 2 mg/kg, followed 10 minutes later by an infusion at a rate of 40 mg/kg/h for 30 minutes (total dose, 20 mg/kg). Plasma MBF concentrations were measured by high-performance liquid chromatography.
Results—The mean peak concentration during MBF infusion was 34.2 ± 6.4 µg/mL. The IV administration of the MBF bolus did not alter any cardiovascular variable in isoflurane-anesthetized dogs. Significant changes were found during infusion when a cumulative dose of 12 mg/kg had been given. The maximal decreases observed at the end of the infusion were 16% in heart rate, 26% in systolic left ventricular pressure, 33% in systolic aortic pressure, 38% in diastolic aortic pressure, 29% in cardiac output, and 12% in QT interval. All dogs recovered rapidly from anesthesia at the end of the experiment.
Conclusions and Clinical Relevance—MBF may safely be used at 2 mg/kg IV in isoflurane-anesthetized dogs, and significant adverse cardiovascular effects are found only when 6 to 8 times the recommended dose is given. (Am J Vet Res 2005;66:2090–2094)