Serum amikacin concentrations in dogs with naturally occurring open wounds treated with topical amikacin in carboxymethylcellulose hydrogel.

Objective: To quantify serum amikacin concentrations in dogs undergoing wound management with topical amikacin (45 mg/mL) 3% carboxymethylcellulose hydrogel.

Study Design: Prospective clinical study.

Sample Population: Eleven client-owned dogs.

Methods: Dogs with naturally occurring wounds, undergoing treatment with topical amikacin gel, were enrolled. A whole blood sample was collected prior to initial application of the gel. Up to a maximum dose of 30 mg/kg of gel, was applied directly on the wound and the wound was bandaged. Serial blood sampling was performed at approximately 2, 4, 8, 12, 18, 24, 32, 40, 48, 56, 64, and 72 h after application of amikacin gel. The sampling schedule was reset following each bandage change and new application of the gel. Up to 20 samples per dog were collected. The Siemens Syva EMIT Amikacin Assay was used to quantify the concentration of amikacin in each blood serum sample. The lower limit of quantification (LLOQ) of the test was 2.5 μg/mL.

Results: Amikacin gel was applied a total of 31 times (dose range, 0.1-24.9 mg/kg). A total of 153 samples were analyzed. Five samples in three different dogs were above the LLOQ at approximately 2 h after gel application (range 2.75-3.82 μg/mL). All other samples were below the LLOQ.

Conclusion: Routine use of amikacin gel for open wound management did not result in serum amikacin levels above 5 μg/mL.

Clinical Significance: Topical amikacin gel may be a safe treatment option for wounds in dogs with resistant infections or biofilms.