Ginsberg J S, Brill-Edwards P, Panju A, Patel A, McGinnis J, Smith F, Dale I, Johnston M, Ofosu F
Department of Medicine, McMaster University, Hamilton, Canada.
Thromb Haemost. 1995 Aug;74(2):602-5.
To determine whether levels of thrombin-antithrombin III (TAT) in plasma, taken two weeks pre-operatively, predict the development of deep vein thrombosis (DVT) in patients undergoing major hip or knee surgery.
Prospective cohort.
Tertiary-care referral centre, university-affiliated hospital.
Ninety eight consecutive patients undergoing elective hip or knee surgery.
All eligible consenting patients were seen in a preoperative clinic two weeks prior to surgery and had blood taken for measurement of plasma TAT level. After surgery, they received a combination of unfractionated heparin 5000 Units 12-hourly subcutaneously, and antiembolism stockings (TEDS), as prophylaxis against DVT. Contrast venography was performed prior to discharge, and according to the results, patients were classified as having proximal (popliteal and/or more proximal) DVT (n = 12), calf DVT (n = 7) or no DVT (n = 79).
The mean TAT level was significantly higher in patients who developed DVT (5.7 micrograms/l) than in those who did not (4.1 micrograms/l), p = 0.035. Using cut-points of 3.5 and 5.5 micrograms/l for the TAT level, patients could be categorized as high, intermediate, and low risk for the development of DVT. The proportion of patients with TAT levels of > or = 3.5 micrograms/l who developed calf or proximal DVT was significantly higher than the proportion of patients with TAT levels of < 3.5 micrograms/l who developed calf or proximal DVT (p = 0.02). The proportion of patients with TAT levels > 5.5 micrograms/l who developed proximal DVT was significantly higher than the proportion of patients with TAT levels of < or = 5.5 micrograms/l who developed proximal DVT (p = 0.03).
This study demonstrates that pre-operative TAT levels correlate with the risk of developing DVT after major orthopedic surgery. Further studies are needed to determine the reason(s) for this observation and whether rational recommendations about prophylaxis and screening for DVT can be made based on the results of a preoperative TAT level.
确定术前两周采集的血浆中凝血酶 - 抗凝血酶III（TAT）水平是否能预测接受大髋关节或膝关节手术患者深静脉血栓形成（DVT）的发生情况。
前瞻性队列研究。
三级医疗转诊中心，大学附属医院。
98例连续接受择期髋关节或膝关节手术的患者。
所有符合条件并同意参与的患者在术前两周于术前门诊就诊，采集血液以测定血浆TAT水平。术后，他们接受皮下注射5000单位普通肝素，每12小时一次，并使用抗栓袜（TEDS）预防DVT。出院前进行静脉造影，根据结果，患者被分类为患有近端（腘静脉及以上）DVT（n = 12）、小腿DVT（n = 7）或无DVT（n = 79）。
发生DVT的患者平均TAT水平（5.7微克/升）显著高于未发生DVT的患者（4.1微克/升），p = 0.035。使用TAT水平3.5和5.5微克/升的切点，患者可被分类为发生DVT的高、中、低风险。TAT水平≥3.5微克/升且发生小腿或近端DVT的患者比例显著高于TAT水平<3.5微克/升且发生小腿或近端DVT的患者比例（p = 0.02）。TAT水平>5.5微克/升且发生近端DVT的患者比例显著高于TAT水平≤5.5微克/升且发生近端DVT的患者比例（p = 0.03）。
本研究表明术前TAT水平与骨科大手术后发生DVT的风险相关。需要进一步研究以确定该观察结果的原因，以及是否可根据术前TAT水平结果对DVT的预防和筛查做出合理建议。
