Changes of thrombelastography in patients undergoing elective primary total knee and total hip replacement with low molecular heparin prophylaxis

BACKGROUND There has been no effective method to monitor the changes of blood coagulation after thromboprophylaxis for elective arthroplasty patients. The objective of this study is to assess the coagulation status of patients undergoing arthroplasty with thromboelastograph (TEG). METHODS Ninety patients undergoing primary elective unilateral arthroplasty were investigated. Thromboprophylaxis continued for at least 10 days. TEG was performed on the day before the operation and on postoperative days 1, 4, and 9. RESULTS The total hip and total knee groups showed significant changes in the distribution of different hypercoagulable states on days 1-4 and on days 4-9. On day 9 after operation, 34 out of 90 (37.8%) of the total hip and total knee patients were found with hypercoagulable state. Of these 34 patients with hypercoagulable state, 26 (76.5%) demonstrated platelet or mixed hypercoagulability. CONCLUSIONS Thrombelastography was an effective way to identify hypercoagulability in patients undergoing elective primary total knee and total hip replacement. Platelet may play an important role in the progress of blood hypercoagulability.