BACKGROUND:Total knee arthroplasty is always associated with peripheral blood loss.Blood transfusion not only involves additional cost and prolongs rehabilitation time,but also carries substantial risk of immunologic reaction and disease transmission.Therefore it is very important to reduce blood loss of total knee arthroplasty.OBJECTIVE:To investigate the efficacy and safety of tranexamic acid on reducing blood loss after total knee arthroplasty.METHODS:We enroled 64 patients with primary osteoarthritis undergoing a unilateral total knee arthroplasty and randomized them into two groups,with 32 patients in each group.Tranexamic acid group: patients received intravenous drop infusion of tranexamic acid dissolved in 250 mL normal saline (10 mg/kg) at 15 minutes before operation; control group: patients just received 250 mL normal saline.Intraoperative blood loss,postoperative blood loss,postoperative hemoglobin levels,amount of blood transfusion,and number of patients requiring blood transfusion were compared.Fibrinogen,prothrombin time and other coagulation indicators were also examined before operation and 3 hours after operation.Deep vein thrombosis in both limbs of al patients was examined bythe color Doppler ultrasonography 30 days after operation.RESULTS AND CONCLUSION:There was no significant difference in intraoperative blood loss between the two groups (P＞0.05).Postoperative volume of blood loss was lower in the tranexamic acid group than in the control group (P＜0.001).The amount of blood transfusion and number of patients requiring blood transfusion were lower in the tranexamic acid group than in the control group (P＜0.001).The postoperative hemoglobin levels were obviously higher in the tranexamic acid group than in the control group (P＜0.001).There was no significant difference in coagulation indicators between two groups at postoperative 3 hours,but D-dimer value in the two groups was significantly higher than that before surgery,and the tranexamic acid group was lower than the control group (P＜0.001).No cases appeared deep vein thrombosis after operation.Experimental findings indicate that,tranexamic acid can effectively reduce postoperative blood loss and blood transfusion,as wel as number of blood transfusions after total knee arthroplasty.And it did not increase the risk of deep vein thrombosis.

ObjectiveTo investigate expression of TGF-β1,CTGF and collagen deposition in skeletal muscle during chronic entrapment of peripheral nerve. MethodsFifty rats were separated into two groups,control group and experimental group. At different time points after operation, the right gastrocnemius of 5rats from each group were collected for further analysis such as HE, Masson stain, immunohistochemical staining,RT-PCR and Western-blot. Results It was observed that axon degeneration occurred during chronic nerve entrapment,and which was in line with reports from other groups.Moreover,it had been demonstrated that after nerve entrapment,skeletal muscles may form fibrosis and degeneration consequently.Within this pathological procedure,expression of TGF-β1. CTGF and deposition of collagenⅠ changed rapidly when compared with control group.ConclusionOverall,these results indicated that these factors may be important during skeletal muscle degeneration after chronic nerve entrapment.