Prevention of venous thromboembolism after knee arthroscopy with low-molecular weight heparin (reviparin): Results of a randomized controlled trial. Venous thromboembolism prophylaxis after head and spinal trauma: intermittent pneumatic compression devices versus low molecular weight heparin. A randomised open-label trial comparing long-term sub-cutaneous low-molecular-weight heparin compared with oral-anticoagulant therapy in the treatment of deep venous thrombosis. Continuous passive motion in the prevention of deep-vein thrombosis: a randomised comparison in trauma patients. Prevention of deep-vein thrombosis after total hip and knee replacement. Low-molecular-weight heparin in combination with intermittent pneumatic compression. Incidence and prophylaxis of deep venous thrombosis in outpatients with injury of the lower limb. A comparison of low-molecular-weight heparin and combined therapy of low-molecular-weight heparin with an anti-inflammatory agent in the treatment of superficial vein thrombosis. Prevention of deep-vein thrombosis in ambulatory arthroscopic knee surgery: A randomized trial of prophylaxis with low--molecular weight heparin. Use of the low-molecular-weight heparin reviparin to prevent deep-vein thrombosis after leg injury requiring immobilization.
Deep venous thrombosis (DVT) is a common, important complication of major orthopaedic surgery, particularly knee arthroplasty. Knee arthroscopy is increasingly performed on an outpatient basis. Few reports have elucidated the incidence of venous thromboembolism (VTE) in patients undergoing arthroscopic surgery receiving no prophylaxis. The objective of the present trial was to evaluate the risk of VTE in those patients and to determine efficacy and safety of a low-molecular weight heparin (LMWH) in preventing VTE.
                This is the first controlled randomized trial using objective diagnostic methods with blinded outcome assessment to reveal the incidence of VTE in outpatient arthroscopy and determine efficacy and safety of a LMWH (reviparin sodium) in preventing VTE in these patients.
                There were 262 patients undergoing elective knee arthroscopy prospectively randomized to receive either no treatment or reviparin once daily subcutaneously for 7 to 10 days. The blindly assessed primary outcome measure was the incidence of DVT detected by compression color-coded sonography. Both groups were comparable with regard to demographics and baseline characteristics.
                239 patients were evaluable (122 no treatment, 117 receiving LMWH). 6 DVT were detected - 5 in the control group (5/117 - 4.1%) and only one in the active treatment group (1/116 - 0.85%). This particular patient had a low level of protein C and a subnormal level of protein S. The odds ratio of 4.95 approximates a relative risk reduction of about 80%. Treatment with reviparin was safe and well tolerated. There was no major bleeding, four patients with minor bleedings. One patient had a transitory fall in platelet count below 100 giga-particles/L without any clinical symptoms.
                Patients undergoing knee arthroscopy have a moderate risk of VTE and effective prophylaxis can be achieved with LMWH (reviparin). Although there are alternative methods and drugs for preventing venous thromboembolism (VTE), it is not clear which modality is most suitable and efficacious for patients with severe (stable or unstable) head/spinal injures. The aim of this study was to compare intermittent pneumatic compression devices (IPC) with low-molecular-weight heparin (LMWH) for preventing VTE. We prospectively randomized 120 head/spinal traumatized patients for comparison of IPC with LMWH as a prophylaxis modality against VTE. Venous duplex color-flow Doppler sonography of the lower extremities was performed each week of hospitalization and 1 week after discharge. When there was a suspicion of pulmonary embolism (PE), patients were evaluated with spiral computed tomography. Patients were analyzed for demographic features, injury severity scores, associated injuries, type of head/spinal trauma, complications, transfusion, and incidence of deep venous thrombosis (DVT) and PE. Two patients (3.33%) from the IPC group and 4 patients (6.66%) from the LMWH group died, with their deaths due to PE. Nine other patients also succumbed, unrelated to PE. DVT developed in 4 patients (6.66%) in the IPC group and in 3 patients (5%) in the LMWH group. There was no statistically significant difference regarding a reduction in DVT, PE, or mortality between groups ( p = 0.04, p > 0.05, p > 0.05, respectively). IPC can be used safely for prophylaxis of VTE in head/spinal trauma patients. To evaluate whether low-molecular-weight heparin (LMWH) could be equally (or more) effective than oral anti-vitamin-K agents (AVK) in the long-term treatment of deep venous thrombosis (DVT).
                A randomised, open-label trial.
                In this trial, 241 patients with symptomatic proximal DVT of the lower limbs confirmed by duplex ultrasound scan were included. After initial LMWH, patients received 6 months of treatment with full therapeutic dosage of tinzaparin or acenocoumarol. The primary outcome was the 12-month incidence of symptomatic recurrent venous thrombo-embolism (VTE). Duplex scans were performed at 6 and 12 months.
                During the 12-month period, six patients (5%) of 119 who received LMWH and 13 (10.7%) of 122 who received AVK had recurrent VTE (p=0.11). In patients with cancer, recurrent VTE tended to be lower in the LMWH group (two of 36 [5.5%]) vs. seven of 33 [21.2%]; p=0.06). One major bleeding occurred in the LMWH group and three in the AVK group. Venous re-canalisation increased significantly at 6 months (73.1% vs. 47.5%) and at 12 months (91.5% vs. 69.2%) in the LMWH group.
                Tinzaparin was more effective than AVK in achieving re-canalisation of leg thrombi. Long-term tinzaparin was at least as efficacious and safe as AVK for preventing recurrent VTE, especially in patients with cancer. There is a high risk of venous thromboembolism when patients are immobilised following trauma. The combination of low-molecular-weight heparin (LMWH) with graduated compression stockings is frequently used in orthopaedic surgery to try and prevent this, but a relatively high incidence of thromboembolic events remains. Mechanical devices which perform continuous passive motion imitate contractions and increase the volume and velocity of venous flow. In this study 227 trauma patients were randomised to receive either treatment with the Arthroflow device and LMWH or only with the latter. The Arthroflow device passively extends and plantarflexes the feet. Patients were assessed initially by venous-occlusion plethysmography, compression ultrasonography and continuous wave Doppler, which were repeated weekly without knowledge of the category of randomisation. Those who showed evidence of deep-vein thrombosis underwent venography for confirmation. The incidence of deep-vein thrombosis was 25% in the LMWH group compared with 3.6% in those who had additional treatment with the Arthroflow device (p < 0.001). There were no substantial complications or problems of non-compliance with the Arthroflow device. Logistic regression analysis of the risk factors of deep-vein thrombosis showed high odds ratios for operation (4.1), immobilisation (4.3), older than 40 years of age (2.8) and obesity (2.2). After total hip (THR) or knee replacement (TKR), there is still an appreciable risk of developing deep-vein thrombosis despite prophylaxis with low-molecular-weight heparin (LMWH). In a prospective, randomised study we examined the efficacy of LMWH in combination with intermittent pneumatic compression in patients undergoing primary unilateral THR or TKR. We administered 40 mg of enoxaparin daily to 131 patients combined with either the use of intermittent pneumatic compression or the wearing of graduated compression stockings. Compression ultrasonography showed no evidence of thrombosis after LMWH and intermittent pneumatic compression. In the group with LMWH and compression stockings the prevalence of thrombosis was 28.6% (40% after TKR, 14% after THR). This difference was significant (p < 0.0001). In the early post-operative phase after THR and TKR, combined prophylaxis with LMWH and intermittent pneumatic compression is more effective than LMWH used with graduated compression stockings. 253 outpatients were included in a prospective randomized study. All patients had incidence of injuries of the lower limb immobilized by a plaster cast. 126 patients (group I) received a subcutaneous injection of Fraxiparin daily, and 127 patients (group II) received no thromboprophylaxis. Without prophylaxis 21 (16.5%) cases developed a thrombosis, and with prophylaxis a thrombosis could be proven in 6 (4.8%) patients only (p < 0.01). Thus, for all patients with an injury of the lower limb being immobilized by a plaster cast, a thromboprophylaxis with a low-molecular-weight heparin is recommended. The optimal treatment of superficial vein thrombosis (SVT) of the leg has not been determined yet. The aim of this study is to evaluate the efficacy of low-molecular-weight heparin (LMWH) as compared with combined therapy of LMWH with an anti-inflammatory agent in treatment of SVT.
                Fifty patients with SVT of the greater saphenous vein were randomly assigned to be treated with Ca-nadroparin 190 IUAxa/kg in a single dose or with same dose of Ca-nadroparin and 60 mg oral acemetacine twice daily for 10 days. The efficacy of the two treatments to relieve symptoms and signs was evaluated by using visual analogue scale.
                Significant improvements were achieved for both groups after the treatment in terms of all four symptoms (P < 0.001). Treatment scores were in favour of LMWH with anti-inflammatory agent treatment group to relieve all four symptoms. The most significant and remarkable results obtained were for the reduction of pain and local tenderness (P < 0.05). No patient experienced major complications or mortality in either group.
                The results of this study suggest that the combined therapy of LMWH with an anti-inflammatory agent is more effective than LMWH. It may be an important option in the standard treatment of SVT. The risk of deep vein thrombosis (DVT) in patients undergoing arthroscopic knee surgery is not well known. The purpose of this study was to determine the incidence of DVT, to demonstrate the efficacy of a perioperative and postoperative prophylaxis against thromboembolism with use of low--molecular weight heparin (LMWH), and to show the safety and feasibility of LMWH administration.
                Prospective, single-blind, randomized clinical trial.
                There were 218 consecutive outpatients scheduled for ambulatory arthroscopic knee surgery eligible. Of these, 130 patients were randomized to a treatment group with LMWH (dalteparin: 2,500 IU less-than-or-equal70 kg and 5,000 IU >70 kg, started perioperatively and given once daily for 4 weeks; n = 66) and a control group (n = 64) with no prophylaxis. To detect DVT, all patients underwent bilateral compression ultrasonography before and 12 and 31 days after surgery.
                Among the 130 patients studied, thromboembolism was significantly lower in the treatment than in the control group: 1 of 66 (1.5%) versus 10 of 64 (15.6%); 95% confidence interval, 7.8% to 26.8%; P =.004. Eighty percent of DVT occurred within the first 14 postoperative days. No severe side effects of LMWH were observed. Only 5% of patients refused continued subcutaneous LMWH injections.
                In patients undergoing ambulatory arthroscopic knee surgery without antithrombotic prophylaxis, the risk of DVT is high. Perioperative and postoperative prophylaxis with dalteparin is an effective and safe means of reducing this risk. Deep-vein thrombosis is a well-recognized complication after trauma to the legs and subsequent immobilization, but there are no generally accepted approaches to preventing this complication.
                We performed a prospective, double-blind, placebo-controlled trial to evaluate the efficacy and safety of subcutaneous reviparin (1750 anti-Xa units given once daily) in 440 patients who required immobilization in a plaster cast or brace for at least five weeks after a leg fracture or rupture of the Achilles tendon. The study drug was given throughout the period of immobilization. Venography of the injured leg was performed within one week after removal of the plaster cast or brace, or earlier if there were symptoms suggesting deep-vein thrombosis.
                Data on efficacy and end points were available for 371 patients. Deep-vein thrombosis was diagnosed in 17 of the 183 patients randomly assigned to receive reviparin (9 percent) and in 35 of the 188 patients randomly assigned to receive placebo (19 percent) (odds ratio, 0.45; 95 percent confidence interval, 0.24 to 0.82). Most of the thromboses were distal (14 in the reviparin group and 25 in the placebo group). There were two cases of pulmonary embolism, both in patients in the placebo group who also had proximal deep-vein thrombosis. There were no differences between the two groups with respect to bleeding or other adverse events.
                Deep-vein thrombosis is common in persons with leg injury requiring prolonged immobilization. Reviparin given once daily appears to be effective and safe in reducing the risk of this complication.
                Copyright 2002 Massachusetts Medical Society
Use of LMWH in outpatients significantly reduces VTE when immobilization of the lower leg is required.