Efficacy On Blood Loss Control By Tranexamic Acid During Primary Unilateral Total Knee Replacement

Background:Osteoarthritis (OA) is the commonest arthritis that happens to knee joint, which chronically incurs degeneration and loss of articular cartilage and regeneration of joint margin and subchondral bone. Knee osteoarthritis is common among the aged, both males and females. The major symptoms includes slow and continuous ache of various level in the beginning and then the pain gradually adds up, causing degeneration and desquamation of cartilage surface, arthroncus, severe osteophyte hyperplasia around knee joint, and narrowing between joints. Patients of advanced stage will feel sharp growth in pain, and their lines of forces in lower limbs will change, accompanied by different degree of bowleg or knock-knee, which renders great inconveniences for their activity and huge loss for quality life. Clinic researches have verified that patients with knee diseases can be perfectly treated with total knee arthroplasty (TKA), considering the ineffectiveness of conservative treatment. TKA can effectively relieve the pain and restore joint functions, thus is being accepted by more and more patients in China.Knee joint is the largest and most complicated within human body which contains multitude of synovia and blood supply. For patients who take their first TKA, large amount of synovia and osteophyte need to be removed while femora and tibia need osteotomy from several angles. The operation causes much trauma and osteotomy, and the objects tend to be aged people. Red bone marrow of aged patients decreases and hematopoiesis becomes poor, and the ability to rectify anemia is weak, all these result in large blood loss during perioperative period and persistent anemia. Reports pointed out that the amount of blood loss in TKA could be600-1550ml. Because of poor ability to rectify anemia, it requires allogenic blood transfusion to ensure the patients while the indications of anemia matches that of transfusion. However, side effect and transfusion diseases caused by allogenic blood transfusion have been frequently reported, including fever, allergy, urticarial, bacteremia, Treponema pallidum virus, cytomegalovirus, and HIV infection and so on. Therefore, to minimize blood loss and transfusion has been the focus for orthopedic surgeons. This study will start with the focus.Objective:This research aims to contrast patients using tranexamic acid during TKA with patients who are not treated with tranexmic acid during TKA under the same circumstances and to figure out the differences in dominant blood loss, hidden blood loss, transfusion population and transfusion ration. The research is to explore and discuss the impact of tranexamic acid on blood loss during primary unilateral TKA, considering dominant blood loss as well as hidden blood loss. MethodsAccording to randomized control principle,90patients who need unilateral total knee replacement in this center from August2011to November2012are sampled, among which,22males, and68females, aging from55to81, and the average age is69.28. The course lasts from2to16. The patients are randomly divided into experimental group and control group (n=45). Experimental group are injected with100ml of tranexamic acid (Volume100ml:0.5g tranexamic acid and0.85g Nacl) through intravenous drip while loosening the tourniquets, and the control group are treated with equal amount of physiological saline. Then the dominant blood loss, hidden blood loss, blood transfusion population and ratio of each group are compared, accompanied by observing clinic symptoms of pulmonary embolism and lower limb DVT. And Doppler ultrasound examine on lower extremity will stand by if necessary.ResultsDominant and hidden blood loss of patients from experimental group is apparently lower than that of patients from control group, and the difference is significant (p<0.05); and the transfusion population and ratio of patients from experimental group is lower than that of patients from control group, and the discrepancy is significant (p<0.001); within both groups no deep vein thrombosis and cardiovascular complications were found14days after operation. One patient suffered dizziness, nausea and vague sight10days after the operation and was diagnosed with congenital cerebrovascular malformation. All patients were discharged from hospital successfully.Conclusion1. Tranexamic acid can largely control and decrease dominant blood loss after primary unilateral TKA2. Tranexamic acid can largely control and decrease hidden blood loss after primary unilateral TKA3. Tranexamic acid can largely control and decrease population and ration of transfusion after primary unilateral TKA4. Right use of tranexmic acid can increase no risk of lower extremity DVT.