Evaluation of 10-minute versus 30-minute tourniquet time for intravenous regional limb perfusion with amikacin sulfate in standing sedated horses.

The objective of the article is to determine the synovial fluid concentrations of amikacin sulfate (AS) after performing an intravenous regional limb perfusion (IVRLP) with the tourniquet in place for 10 minutes and compare this with 30 minutes. This is a randomised crossover experimental design. Animals were seven healthy adult horses. Horses underwent two IVRLP procedures in a randomised, crossover design. The horses received IVRLP with 2 g AS diluted to 60 ml using 0.9% saline in the cephalic vein of alternate limbs with the tourniquet in place for either 10 or 30 minutes, with a washout period between procedures. Movement of the horses was recorded. Synovial fluid was collected from the radiocarpal and metacarpophalangeal joints at five minutes and 24 hours after IVRLP, and amikacin concentration was compared between groups. Amikacin was quantified by a fluorescence polarisation immunoassay. There was no significant difference between the synovial amikacin concentrations noted between 10 minute and 30 minute IVRLP. Horses in the 30 minute tourniquet application group demonstrated more movement than the 10 minute tourniquet group. There was a significant difference between groups with regard to the systemic venous blood concentration of amikacin one minute after tourniquet release with mean systemic venous blood concentrations of AS being higher (P=0.001) in the 10 minute group. Ten minute application of a wide elastic tourniquet may be sufficient when performing IVRLP in standing sedated horses.