Co-administration of hyaluronic acid with local anaesthetics shows lower cytotoxicity than local anaesthetic treatment alone in bovine articular chondrocytes

Abstract

ObjectiveTo study the effect of hyaluronic acid (HA) on local anaesthetic chondrotoxicity in vitro.MethodsChondrocytes were harvested from bovine femoral condyle cartilage and isolated using collagenase-containing media. At 24 hours after seeding 15 000 cells per well onto a 96-well plate, chondrocytes were treated with media (DMEM/F12 + ITS), PBS, 1:1 lidocaine (2%):PBS, 1:1 bupivacaine (0.5%):PBS, 1:1 lidocaine (2%):HA, 1:1 bupivacaine (0. 5%):HA, or 1:1 HA:PBS for one hour. Following treatment, groups had conditions removed and 24-hour incubation. Cell viability was assessed using PrestoBlue and confirmed visually using fluorescence microscopy.ResultsMedia-treated groups had a mean of 1.55×104 cells/well (sem 783). All treated cells showed statistically significant reduced viability when compared with media alone (all p < 0.003). Cells treated with bupivacaine + HA (6.70×103 cells/well (sem 1.10×103)) survived significantly more than bupivacaine (2.44×103 cells/well (sem 830)) (p < 0.001). Lidocaine + HA (1.45×103 cells/well (sem 596)) was not significantly more cytotoxic than lidocaine (2.24×103 cells/well (sem 341)) (p = 0.999). There was no statistical difference between the chondrotoxicities of PBS (8.49×103 cells/well (sem 730) cells/well) and HA (4.75×103 cells/well (sem 886)) (p = 0.294).ConclusionsHA co-administration reduced anaesthetic cytotoxicity with bupivacaine but not lidocaine, suggesting different mechanisms of injury between the two. Co-administered intra-articular injections of HA with bupivacaine, but not lidocaine, may protect articular chondrocytes from local anaesthetic-associated death.Cite this article: Bone Joint Res 2013;2:270–5.