(Introduction). In Total Knee Arthroplasty (TKA), closed drains have been conventionally used to prevent hematoma. Recently reported “no-drain” methods have been demonstrated to be safe and effective, especially for decreasing hemorrhage. However, there has been no report of a major study on a no-drain method in simultaneous bilateral TKA, only a few small studies. Therefore, this study evaluated the efficacy of no-drain placement in simultaneous bilateral TKA. (Methods). Our study included 75 patients (150joints) with preoperative hemoglobin(Hb) level of at least 11.0 g/dl who underwent simultaneous bilateral TKA performed by the same surgeon in our department between January 2012 and December 2013. There were 12men and 63women, of average age 70.7 ± 7.9years (mean ± SD) and BMI 25.6± 3.8 (mean ± SD). Among them 72 patients had knee osteoarthritis and 3 patients had rheumatoid arthritis. The patella was not replaced in any of the cases. TKAs were performed separately on each knee. A tourniquet was applied between the initial skin incision and the postoperative dressing, and 1000 mg of tranexamic acid was injected into each joint after wound closure. (Results). The surgical time per patient was 136.6 ± 30.3 minutes (mean ± SD). The Hb levels (mean ± SD) were 13.0 ± 1.1 g/dl before surgery, 10.9 ± 1.2 g/dl on the day after surgery. The estimated total blood loss until the day after surgery was 558.4 ± 253.9 ml (mean ± SD). No patient experienced hypotension requiring vasopressor or rapid fluid therapy between the end of surgery and the day after surgery, and no complication caused by a sudden change of hemodynamics was found in any case of bilateral TKA. A gait training/range of motion exercise while bearing full load of the body weight was initiated from the day after surgery. This allowed patients to be discharged from our hospital in an average of 6.1days (range 5–11days)after surgery. There were no serious complications that occurred within three months after surgery. (Discussion). In cases of TKA with closed drain, even in unilateral surgery, excessive hemorrhage may be discharged through drain tubes for the first few hours after surgery. Hypotension caused by postoperative sudden hemorrhage or burden on the cardiovascular system seem to be major issues. In this study, simultaneous bilateral TKA were performed without suction drainage. The estimated blood loss until the day after surgery was approximately 560 ml. As sudden hypotension causing shock was not found, the
