Efeitos tóxicos do ácido tranexâmico e da povidonaiodo na cartilagem articular de coelhos

Abstract

Introcuction: the topical intra-articular use of tranexamic acid (ATX) and povidoneiodine (PVPI) in knee arthroplasties has been increasing over the past few years due to evidence from the literature confirming reductions in blood loss, need for blood transfusion, and rates of post-operative surgical site infection, respectively. However, further studies are required on the toxicity of these substances to residual cartilage in patients submitted to unicompartmental knee arthroplasty and unresurfaced patella in total knee arthroplasty. Objectives: to evaluate the effects of topical use of ATX 20mg/kg and/or 0.35% PVPI on knee joint cartilage in an experimental model of rabbits. Material and Method: 44 male rabbits less than six months old, New Zealand breed, were randomly assigned to four groups (control, ATX, PVPI and PVPI + ATX) had knee joint cartilage exposed to physiological saline SF 0,9% (control group), ATX, PVPI and PVPI followed by ATX. Sixty days after the surgical procedure, the animals were sacrificed and osteochondral fragments of the distal femur were obtained. Histological sections of cartilage from this area were stained with hematoxylin/eosin and toluidine blue. The following cartilage parameters were evaluated through the Mankin histological/histochemical grading system: structure, cellularity, glycosaminoglycan content in the extracellular matrix and integrity of the tidemark. Results: the isolated use of PVPI causes changes in cartilage structure, cellularity and glycosaminoglycan content, whereas the isolated use of ATX alters the glycosaminoglycan content. The sequential use of PVPI + ATX causes more pronounced alterations in the extracellular matrix, structure and cellularity. Conclusion: the data suggest that topical intra-articular use of tranexamic acid 20mg/kg after closure of the joint capsule and intraoperative lavage with 0.35% povidone-iodine solution for three minutes are toxic to articular cartilage in an experimental in vivo study in rabbit knee. It has also been shown that the sequential use of these substances presents greater toxicity to the articular cartilage.