SCREENING FOR PROXIMAL DEEP VENOUS THROMBOSIS USING B-MODE VENOUS ULTRASONOGRAPHY FOLLOWING MAJOR HIP-SURGERY - IMPLICATIONS FOR CLINICAL MANAGEMENT

Despite antithrombotic prophylaxis, deep vein thrombosis (DVT) remains a frequent complication following major hip surgery. Most of the post operative DVTs are asymptomatic but may result in fatal pulmonary embo lism. Thus, detection of these events remains a clinical challenge. Th e present study evaluated prospectively the clinical usefulness of a s ystematic screening for proximal DVT in 173 consecutive patients under going major hip surgery and given systematic antithrombotic prophylaxi s. On the 12th postoperative day, realtime B-mode ultrasonography of l ower limbs veins detected 12 patients (7%) with proximal DVT. None of the individual or surgical characteristics of the patients could help to predict postoperative DVT. Because the sensitivity of ultrasonograp hy for diagnosing DVT in asymptomatic patients may be low and because we did not screen for distal DVT, it was speculated that up to half pr oximal DVT and up to 75% of all DVT might have been missed by the scre ening. Therefore, low-dose oral anticoagulation with an INR 1.5-2.0 mi ght be the most cost-effective modality in the postoperative period af ter the initial perioperative prophylaxis with low-dose heparin, low-m olecular-weight heparins or intermittent pneumatic compression boots. Oral anticoagulant treatment might be continued for a total duration o f 6 weeks, thereby also providing efficient therapy of undiagnosed dis tal DVT and prolonged for 3 months in patients with proximal DVT prove n by systematic ultrasonographic screening at the time of discharge. T he benefit-to-risk ratio of this management strategy deserves further evaluation in a specially designed, prospective trial.