Chotanaphuthi Thanainit, Heebthamai Danai, Taweewuthisub Worasun, Thiengwittayaporn Satit, Roschan Suwat, Kanchanaroek Kris
Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand.
J Med Assoc Thai. 2009 Dec;92 Suppl 6:S6-10.
Despite prophylaxis, deep vein thrombosis (DVT) still occurs frequently after elective knee surgery. Hence, it would be helpful if the high-risk DVT patients could be identified before surgery so the adequate prophylaxis could be given. A normal plasma D-dimer level effectively rules out acute DVT patients who were classified as having low clinical probability. In many studies, one coagulation activation marker was measured to observe their role in preoperative prediction ofDVT after major hip or knee surgery. In this study, the preoperative plasma level of D-dimer in patients undergoing total knee arthroplasty (TKA) was collected, and correlated with the results of postoperative venography
To determine whether levels of D-dimer in plasma, taken two weeks preoperatively, predicts the development of DVT in patients undergoing TKA.
Fifty-nine consecutive patients undergoing TKA were seen in a preoperative clinic two weeks prior the surgery and had blood taken for measurement of plasma D-dimer. After surgery, they did not receive prophylaxis anticoagulant. Ascending contrast venography of both lower extremities was performed in all cases between the 6th-l0th postoperative day or earlier if clinical symptoms occurred.
Plasma D-dimer was measured preoperatively in 59 patients undergoing TKA. DVT was detected by venography in 31 (53%) patients. At a cutoff or 500 ng/ml, the sensitivity, specificity, positive and negative predictive values of the preoperative D-dimer concentration for the development of subsequent DVT were 58%, 46%, 55%, and 50%, respectively.
The results of the present study suggested that preoperative plasma measurement of D-dimer concentration is not useful for predicting DVT in patients undergoing TKA.
尽管采取了预防措施，但择期膝关节手术后深静脉血栓形成（DVT）仍频繁发生。因此，如果能在手术前识别出高危DVT患者，以便给予适当的预防措施，将会很有帮助。正常的血浆D-二聚体水平可有效排除临床概率较低的急性DVT患者。在许多研究中，测量一种凝血激活标志物以观察其在髋关节或膝关节大手术后DVT术前预测中的作用。在本研究中，收集了接受全膝关节置换术（TKA）患者的术前血浆D-二聚体水平，并将其与术后静脉造影结果相关联。
确定术前两周采集的血浆D-二聚体水平是否能预测接受TKA患者DVT的发生。
59例连续接受TKA的患者在术前两周的门诊就诊，并采集血液用于测量血浆D-二聚体。术后，他们未接受预防性抗凝治疗。所有病例均在术后第6至10天或更早（如果出现临床症状）进行双下肢上行静脉造影。
对59例接受TKA的患者进行了术前血浆D-二聚体测量。静脉造影检测到31例（53%）患者发生DVT。以500 ng/ml为临界值，术前D-二聚体浓度对后续DVT发生的敏感性、特异性、阳性和阴性预测值分别为58%、46%、55%和50%。
本研究结果表明，术前血浆D-二聚体浓度测量对预测接受TKA患者的DVT无用。
