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FACTORS RELATED TO BLOOD LOSS IN TOTAL KNEE ARTHROPLASTY

Introduction:Main population of total knee arthroplasty are elderly group which contained of risks from procedure and medical condition. The amount of blood loss in TKA vary in different studies. Blood loss from TKA may cause the change of hemodynamic status, risked to cardiovascular morbidity or mortality. Allogenic blood transfusion, associated with many immunological and transfusion complications, increased cost of surgery. Factors associated with blood loss should controlled to decreased blood loss and complications. Objectives:Determination of risk factors for blood loss is a significant step toward blood management. This study is also used calculated blood loss, which more accurate than visible blood loss. Methods:Medical records of 517 patients who underwent TKA from 2011 to 2016 were examined, blood loss was calculated by Gross' formula. Pearson 's correlation and multiple regression analyses were performed to identify factors associated to blood loss. Results:The mean calculated blood loss decreased yearly from 602.94ml to 107.78ml in 2016. There is “zero” transfusion in 2016. Radivac drain, patellar resurfacing, modified Robert Jones bandage and higher postoperative pain score related to increased blood loss after TKA according to Pearson's correlation. Multiple regression analysis revealed significant independent predictors related to blood loss are radivac drain, intravenous tranexamic acid, postoperative pain score and body mass index. Conclusions :Awareness in low BMI patient, avoid radivac drain, routine using of intravenous tranexamic acid and good postoperative pain control can reduce blood loss and transfusion for a patient undergoing TKA.