The thromboprophylactic effect of a low-molecular-weight heparin (Fragmin) in hip fracture surgery. A placebo-controlled study. Heparin prophylaxis of deep vein thrombosis in patients with a fractured neck of the femur. Thromboembolism after elective and post-traumatic hip surgery--a controlled prophylactic trial with dextran 70 and low-dose heparin. Preventing venous thromboembolism in elderly patients with hip fractures: studies of low-dose heparin, dipyridamole, aspirin, and flurbiprofen. Effectiveness of pneumatic leg compression devices for the prevention of thromboembolic disease in orthopaedic trauma patients: a prospective, randomized study of compression alone versus no prophylaxis. [Prevention of thromboembolism in hip fracture: unfractionated heparin versus low molecular weight heparin ( a prospective, randomized study)]. The value of low dosage heparin for the prophylaxis of thromboembolism in patients with transcervical and intertrochanteric femoral fractures. The A-V Impulse System reduces deep-vein thrombosis and swelling after hemiarthroplasty for hip fracture. A prospective double-blind trial of a low molecular weight heparin once daily compared with conventional low-dose heparin three times daily to prevent pulmonary embolism and venous thrombosis in patients with hip fracture. Low molecular weight heparin (Alfa LHWH) compared with unfractionated heparin in prevention of deep-vein thrombosis after hip fractures. Sequential mechanical and pharmacological thromboprophylaxis in the surgery of hip fractures. A pilot study. Low-dose heparin in femoral neck fractures. Prevention of thromboembolism in hip-fracture patients. Comparison of low-dose heparin and low-molecular-weight heparin combined with dihydroergotamine. Low-dose heparin for prevention of venous thromboembolism in total hip arthroplasty and surgical repair of hip fractures. Cyclic sequential compression of the lower limb in prevention of deep venous thrombosis. Comparative double-blind study of two dosage regimens of low-molecular weight heparin in elderly patients with a fracture of the neck of the femur. Deep vein thrombosis in elderly Hong Kong Chinese with hip fractures detected with compression ultrasound and Doppler imaging: incidence and effect of low molecular weight heparin. Thromboprophylaxis in hip fracture surgery: a pilot study comparing danaparoid, enoxaparin and dalteparin. The TIFDED Study Group. Effect of low-dose heparin and dihydroergotamine on frequency of postoperative deep-vein thrombosis in patients undergoing post-traumatic hip surgery. Randomized study of adjusted versus fixed low dose heparin prophylaxis of deep vein thrombosis in hip surgery. Low-dose heparin in proximal femoral fractures. Failure to prevent deep-vein thrombosis. [Prevention of venous thromboemboli with low doses of heparin in patients with proximal femur fractures].
A prospective, randomized, double-blind trial concerning thromboprophylaxis in 82 patients in whom hip fracture surgery was performed was conducted to compare a new low-molecular-weight heparin (Fragmin) with placebo. Deep venous thrombosis (DVT) was detected by 125-I-fibrinogen uptake test followed by ascending phlebography when positive. Sixty-eight patients completed the study, and a 50% reduction in the incidence of DVT was demonstrated: nine of 30 patients in the treatment group (30%) and 22 of 38 patients in the placebo group (58%) developed DVT. This significant difference was achieved by one daily dose of 5000 IU Fragmin subcutaneously, commenced preoperatively and continued for six days. There were no differences in bleeding or other complications in the two groups. Fragmin given once daily offers an effective and safe thromboprophylaxis in hip fracture surgery. A double-blind controlled clinical trial of the efficacy of the prophylactic subcutaneous administration of calcium heparin in preventing deep vein thrombosis has been conducted in 50 patients with a fractured neck of the femur. Heparin was given every eight hours in a dose of 100 international units per kilogram of body weight and was commenced as soon as possible after the patient's admission to hospital. Treatment was continued for two weeks. In the placebo group, 12 of 25 patients developed a deep venous thrombosis and in five of these patients the thrombosis propagated to the thigh. There were no deep venous thromboses in the heparin-treated group during the two weeks of treatment, but four patients developed a deep venous thrombosis within a week of stopping the heparin. The heparin regime was safe; operative blood loss was not increased, nor was there an increased incidence of wound complications as compared to the placebo group. A prospective randomized controlled study has been undertaken to evaluate two different prophylactic treatments against postoperative thromboembolic complications after hip surgery. Patients with hip fracture (77) and patients undergoing elective hip arthroplasty (213) were separately randomized into one of three groups: control, dextran 70, or low-dose heparin. Deep vein thrombosis was diagnosed in both groups with the 125I-fibrinogen test and pulmonary perfusion defects in the arthroplasty group with a combination of pulmonary X-ray and perfusion scintigraphy. The frequency of thrombosis was significantly higher in untreated hip fracture patients than in untreated arthroplasty patients. In hip fracture patients both treatments significantly reduced the frequency of thrombosis. Only dextran reduced the frequency of major thrombosis and in the heparin group one fatal pulmonary embolism occurred. After elective hip surgery the overall frequency of thrombosis was not influenced by the two treatments, but with dextran 70 thigh thrombi were reduced and with low-dose heparin the frequency of bilateral thrombosis was reduced. Two patients in the control group died of pulmonary embolism, but the frequency of pulmonary perfusion defects was not influenced by the treatment. Bleeding and transfusions were the same in the three groups. Low-dose heparin, dipyridamole (alone and in combination with aspirin), and flurbiprofen were evaluated as potential prophylactic agents against deep venous thrombosis in elderly patients with hip fractures. None of the agents that modify platelet behaviour could reduct the frequency of isotopically diagnosed venous thrombosis. Low-dose heparin reduced the overall frequency of venous thrombosis and its extent as judged by the frequency of bilaterally abnormal scans, but this reduction did not achieve statistical significance. A prospective, randomized clinical trial in 304 orthopaedic trauma patients with hip and pelvic fractures was conducted to investigated the effectiveness of pneumatic sequential leg compression devices (PSLCDs) for the prevention of thromboembolic disease. The control group received no specific form of prophylaxis. Patients were followed by venous Doppler, duplex can, and ventilation perfusion lung scans. The study end-point was documented pulmonary embolism and/or deep vein thrombosis. The incidence of a venous thromboembolic event in the control group was 11% and in the experimental group 4%. This difference was statistically significant (p = 0.02). These patients were also stratified into hip and pelvic fracture groups. In the hip fracture patients, the control group had a thromboembolic event incidence of 12% and the experimental group 4%. This difference was also statistically significant (p = 0.03). In the pelvic fracture group there was a thromboembolic incidence of 11% in the controls, demonstrating this patient population to be at significant risk. In this group, the PSLCDs were not statistically shown to be effective. Pneumatic leg compression devices are effective in reducing the incidence of thromboembolic events in patients with hip fractures. In a prospective, randomized study in patients with hip fracture we discuss whether a single dose of low-molecular-heparin (Sandoparin) has the same effect as a tripple dose of standard-heparin (Liquemin: 3 x 5000 I.E.) The first dose of low-molecular-heparin respectively standard-heparin is given in the emergency room before the operation. Between 4th and 6th day following operation the patients were screened for deep vein thrombosis: Clinical examination, Liquid Crystal Contact Thermography (LCCT), colour coded ultrasound examination and with phlebography. 33 patients have been treated with standard-heparin and 35 with low-molecular-heparin. In the group of standard-heparin 30% of all the patients showed a deep vein thrombosis, whereas only 17% deep vein thrombosis were found in the group treated with low-molecular-heparin. But to reach statistical significance in both groups 60 patients are needed. Postoperative haemorrhagic complications were seen in 6.1% in the group of standard-heparin and in 8% in the group of low-molecular-heparin. The LCCT and the ultrasound examination were compared with the phlebography. The LCCT had a sensitivity of 92% and a specificity of 85%. The ultrasound examination had a sensitivity of only 15%! Therefore the ultrasound examination is an unsuitable screening method to detect deep vein thrombosis in patients with fractures of the proximal end of the femur. One hundred and ten female patients, over the age of 60, with intertrochanteric or transcervical fractures were included in a controlled, randomized, clinical trial investigating the value of low dosage heparin in the prophylaxis of deep vein thrombosis. There were 50 completed pairs. Eight (16 per cent) deep vein thromboses occurred in the heparinized group compared with 23 (46 per cent) deep vein thromboses in the control group. The incidence of pulmonary embolism was also reduced. The diagnosis of deep vein thrombosis was made on clinical grounds, supplemented by phlebography and autopsy. There was no difference in the wound hematoma or infection rate. The heparin was commenced on admission to hospital and it is suggested that in this group of patients low dosage heparin prophylaxis should start on admission and not wait until surgery. We performed a prospective randomised controlled trial of the A-V Impulse System in 82 patients treated by hemiarthroplasty for subcapital fracture of the femoral neck. The incidence of proximal deep-vein thrombosis as assessed by Doppler ultrasonography was 23% in the control group and 0% in those using the device (p less than 0.01). Calf and thigh circumferences were measured in both groups at seven to ten days after operation. In the treatment group there was a mean relative reduction of postoperative swelling of the thigh by 3.27 cm (p less than 0.001) and of the calf by 1.55 cm (p less than 0.001). The A-V Impulse System appears to be a safe and effective method of reducing the incidence of proximal deep-vein thrombosis, and of postoperative swelling. In a randomized, prospective, double-blind trial, the effect of conventional low-dose heparin (5,000 units every 8 hours) was compared with that of a low molecular weight fragment (2165 LMWH, Kabi Vitrum AB, starting 2,500 units 2 hr before surgery, and then 5,000 units subcutaneously every morning for 9 days). A total of 90 patients admitted because of hip fracture fulfilled the inclusion criteria and were analyzed for development of pulmonary embolism and deep vein thrombosis: 46 patients were included in the low molecular weight heparin (LMWH) group, and 44 in the conventional heparin group. Two and three, respectively, died before diagnostic tests were performed. In the remaining patients a ventilation-perfusion lung scan was performed 8 days after intervention. In the first 57 patients studied a bilateral ascending venography was performed on the ninth day only if clinical symptoms suggested a deep venous thrombosis. Because of the rate of venous thrombosis detected in those patients was unexpectedly low, venography was requested in the remaining 33 patients, even if the screening tests were negative. Pulmonary embolism occurred in six patients, all in the LMWH group. Deep vein thrombosis occurred in 14 patients in the LMWH group and in six patients in the conventional heparin group. Both differences are statistically significant. Mortality did not differ between the groups, nor did haemorrhagic complications. Our findings suggest that, in patients with hip fracture, LMWH is not useful at the dosage used. Efficacy and safety of a low molecular weight heparin (Alfa LMWH) was compared with unfractionated heparin (UFH) in the prevention of post-operative venous thromboembolism after hip fractures. Forty-nine patients were randomized to treatment with Alfa LMWH 7500 anti-Xa coagulometric units twice daily or with UFH 5000 IU t.i.d. Screening for thrombosis was performed with 125-I-fibrinogen leg scanning and strain-gauge plethysmography. Positive results were confirmed by venography. Five patients in the Alfa LMWH group (20 per cent) developed venographycally proven deep vein thrombosis (DVT) versus seven (29 per cent) in the UFH group. One pulmonary embolism and two deaths occurred in the UFH group and none in the LMWH group. No differences in haemorrhagic complications and blood loss indices were observed. Alfa LMWH appears to be a promising drug for prevention of venous thromboembolism after orthopaedic surgery. A "flexible" schedule of administration is proposed on the basis of the results of plasma anti-Xa assays. Two hundred and thirty-eight patients with femoral neck fractures were entered into a randomised pilot study comparing the use of sequential treatment by 'Flowtron DVT' garments in the perioperative period followed by Enoxaparin (Clexane-Rhône-Poulenc Rorer), and Enoxaparin alone. One hundred and ninety-three patients were excluded indicating the difficulty of achieving pure comparisons in this population. The remaining 44 were randomised: 21 received Enoxaparin from the time of admission, and 23 had sequential treatment. There was no statistically significant difference in the incidence of thromboembolism. Patient preference did not indicate a favoured treatment subjectively. The operation field was drier in the sequential group, although this did not reach significance. Sequential treatment was not shown to be better or worse than treatment with Enoxaparin, but the trends favoured sequential treatment rather than drug treatment alone. The technique allows the operation to be carried out without the problems produced by low dose heparins and mobilisation is not hindered by compression garments. nan In a prospective, double-blind, controlled study, we compared the antithrombotic efficacy of low-dose heparin with dihydroergotamine (A), low-molecular-weight heparin with dihydroergotamine (B), and placebo (C). Two hundred and thirteen patients surgically treated for fractures of the hip were randomly divided into three groups. One hundred and sixty-one patients were analyzed. All thrombi were verified by ascending phlebography. Nine patients died within 1 month after operation. A and B proved to be equally safe but failed to provide any protection against deep-vein thrombosis, although B showed a tendency to reduce the incidence. Mortality within 1 month of operation was unaffected by the type of prophylaxis. Sixty-seven hip-arthroplasty and fifty-two hip-fracture patients participated in a placebo-controlled randomized double-blind study on the effects of low-dose heparin prophylaxis in the prevention of venous thromboembolism. In this study, a positive thromboembolic event meant a positive test by: (1) daily 125I-fibrinogen scanning, (2) contrast venography on the tenth postoperative day, or (3) radionuclide perfusion lung scan in confirmation of suspected clinical pulmonary emboli. Nineteen (59.4 per cent) of thirty-two placebo-treated arthroplasty patients showed evidence of a thromboembolic event in contrast with eight (22.9 per cent) of thirty-five heparin-treated patients (p less than 0.003). Heparin-treated arthroplasty patients required mean blood transfusions of 4.7 units, contrasted with a mean 3.2-unit transfusion requirement for placebo-treated patients (p less than 0.05). The incidence of observed bleeding complications was higher among the heparin-treated patients. Of the twenty-three placebo-treated patients with fracturs, 39.1 per cent had a thromboembolic event, while 41.4 per cent of the twenty-nine who received heparin showed evidence of thromboembolism, demonstrating that low-dose heparin afforded no protection, nor did it affect the incidence of bleeding complications or transfusion requirements in fracture patients. Patients undergoing operations on the hip for either replacement or fracture were chosen for this study. Fifty-two subjects received cyclic sequential compression as well as elevation of the lower limb while another fifty-two patients were treated with only elevation of the lower limb. No other method of prophylaxis for deep venous thrombosis was employed during the study period. Support stockings were used after removal of the compression device. Doppler ultrasound, phleborheography, and, when possible, radioiodinated fibrinogen scanning were used for identification and location of thrombi. A deep-vein thrombosis developed in ten patients (19 per cent) in the control group and in only one patient (2 per cent) in the group that was treated with compression. This difference is statistically significant (p less than 0.05). A randomized double-blind study comparing the efficacy and safety of two different dosage regimens of a low-MW heparin, Enoxaparin (Lovenox) 20 mg twice (group A) or 40 mg once (group B), was carried out in 103 elderly patients with a fracture of the neck of the femur. Distal and proximal thrombosis occurred in 18.3% of patients in group A and in 10.4% in group B. No major hemorrhagic complication was observed, except for two hematomas in each group. This trial suggests that a total daily dose of 40 mg of Enoxaparin can be effective in the prevention of deep vein thrombosis in elderly surgically treated patients and does not involve a major risk of bleeding. Seventy-eight patients of average age 78 years suffering from an unilateral non-pathological hip fracture underwent compression ultrasound and pulsed and colour Doppler examination of both legs. Twenty-three patients were randomly placed on low molecular weight heparin (LMWH). Twenty-nine (37%) suffered deep venous thrombosis (DVT). There was no statistically significant difference in the incidence of DVT between the control and LMWH groups, and the incidence of DVT in elderly Chinese patients after hip replacement for a hip fracture is similar to that in other studies in Caucasians. There were, however, some differences, namely the contiguous nature of the thrombi rather than focal segmental clots, and the absence of propagation or tail formation. Although the numbers are small, this could possibly represent a population difference. There was a significantly increased occurrence of DVTs on the operated side in both groups. Serial ultrasound examination supports evidence that DVTs occur in the 1st week postoperatively, but there were also a number of patients who developed DVTs in the 2nd week. There was no statistically significant difference in overall incidence of DVT between patients on prophylactic heparin and the control group. Patients on prophylactic heparin had no thigh DVTs in comparison to the control group. LMWH may thus be effective in preventing thigh DVTs and pulmonary emboli. A pilot study was performed to compare the thromboprophylactic effect of danaparoid, enoxaparin and dalteparin in patients with hip fracture. The study was a prospective, randomised assessor-blind, four-centre trial. Prophylaxis was given for 9-11 days, whereafter bilateral phlebography was performed. A total of 197 patients were randomised. There were no statistically significant differences in the frequency of deep vein thrombosis, in blood loss or bleeding complications between the three prophylaxis groups. In conclusion, this moderately sized study revealed no statistically significant difference in efficacy or safety between danaparoid, enoxaparin and dalteparin in patients undergoing hip fracture surgery.
                Copyright 2000 S. Karger AG, Basel The effect of low doses of heparin (5000 units of sodium heparin every 12 hours for 10 days) and dihydroergotamine (DHE) (0.5 mg at the same intervals as heparin) on the incidence of deep-vein thrombosis (D.V.T.) in the legs was studied on 210 patients undergoing nailing of a fractured neck of the femur. The patients were allocated randomly to receive heparin (70 patients) or heparin + dihydroergotamine (71 patients) or saline (69 patients, acting as controls). D.V.T. developed in 15 patients in the heparin group, in 12 patients in heparin + DHE group and in 28 patients in the control group. There is a significant difference between the two groups receiving heparin on the one hand and the control group on the other. DHE does not seem to reduce the incidence of D.V.T. any further in this group of patients. A randomized study of adjusted versus fixed low dose heparin prophylaxis has been conducted in 100 patients undergoing surgery for hip replacement or fractured neck of femur. The two types of patients were randomized independently into the adjusted and fixed dose regimens. Patients in the adjusted group were controlled by an activated partial thromboplastin time method particularly responsive to the anticoagulant effect of heparin. The aim was to maintain the peak value just above the upper limit of the normal range. Adjustment of dosage began 24 h after surgery in the replacement group and 24 h after admission in the fracture group. Significant improvement in protection against postoperative deep vein thrombosis, assessed by venography, was observed in the adjusted group undergoing hip replacement (P = 0.013) and overall in both groups (P = 0.017) compared with a conventional fixed dose subcutaneous regimen (calcium heparin 5000 units, 8-hourly). In most instances, adjustment resulted in increased heparin dosage but this was not associated with any evidence of excessive bleeding. The effect of heparin, 5000 units every 8 hours, on deep venous thrombosis in patients with proximal femoral fractures was investigated in a controlled, double blind, randomised study. Heparin or placebo was administered as soon as possible after the fracture, and before 6 hours had passed, and was continued for 14 days. The diagnosis of deep venous thrombosis was made using daily I125 fibrinogen scans. A total of 130 patients endured the trial and the results were registered on a sequential diagram. This showed that the 0-hypothesis could not be rejected, and that consequently no difference in the frequency of deep-vein thrombosis was detected. The value of low dosage heparin in preventing venous thromboembolism was studied in 150 patients with proximal femoral fractures. This was a prospective, randomized, clinical trial, consisting of 116 women and 34 men with a mean age of 73 years (38 to 92). 5000 units of subcutaneous heparin was given twice a day for a fortnight to the heparinized group and the control group was left without. The heparin was commenced on admission to hospital. Deep venous thromboses (D. V. T.) and pulmonary embolism (P. E.) was diagnosed on clinical grounds. Fatal P. E. was verified by necropsy. There was significantly less D. V. T. in the heparinized group than in the control group (p < 0.01) and the incidence of P. E. was smaller in the heparinized group, 0 and 4 per cent respectively. This difference is not statistically significant. There were no significant differences in the amount of blood needed. We recommend routine use of low dosage heparin started on admission to hospital in proximal femoral fractures.