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

Abstract

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.

Regional limb perfusion in horses

“…In a paper summarised on p 585 of this issue of Veterinary Record , Kilcoyne and others (2016) found no difference in synovial antimicrobial concentrations between 10- and 30-minute tourniquet application times. An additional study from the same laboratory found no significant difference in synovial antimicrobial concentration between horses having 20 and 30 minutes of tourniquet application during RLP (Aristizabal and others 2016).…”

“…Furthermore, using a vein proximal to the carpus or tarsus is useful when the distal limb suffers from trauma since it allows for immobilisation of the region with a cast when indicated (Kelmer and others 2012). Recently, most RLP studies have used the cephalic vein and it appears that using the proximal vein is the preferred site for catheter placement (Beccar-Varela and others 2011, Zantingh and others 2014, Aristizabal and others 2016, Kilcoyne and others 2016, Oreff and others 2016, Sole and others 2016). …”

Pharmacokinetics of ceftazidime after regional limb perfusion in standing horses

“…The constant battle against resistant bacteria creates a growing need for the development of more efficient treatments. As a result, significant research effort has recently focused on RLP, such as investigating combinations of antimicrobials, the use of additional types of antimicrobials, and improving the technique …”

Synovial butorphanol concentrations and mechanical nociceptive thresholds after intravenous regional limb perfusion in standing sedated horses

“…Little consensus exists regarding how IVRLP should be performed, which limits direct comparisons between studies and the ability to identify sources of variability. There is debate concerning the ideal technical aspects of the procedure (eg, tourniquet type and number, perfusate volume, perfusion time), and the available data are equivocal . The IVRLP performed here was intended to reproduce that easily performed by the general practitioner, and attempts were made to ensure consistency of the procedure and sample collection.…”

“…Tourniquets are known to cause discomfort in man, so their use is predominantly restricted to anesthetized patients . Their use in minimally sedated horses can similarly result in painful responses, requiring the use of sedation . Tourniquet release is reportedly painful in human patients, and painfulness is also suspected in equine patients because of their repetitive limb movements after removal .…”