***TASK*** the task is to summarize an input biomedical literature in six sentences 
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    Input: PURPOSE We assessed the feasibility of a large r and omized trial intended to determine whether low-dose heparin prophylaxis given throughout hospitalization reduces mortality and morbidity in general medical patients . SUBJECTS AND METHODS Hospitalized general medical patients aged more than 60 years at 5 Department of Veterans Affairs ( VA ) medical centers were r and omized to receive enoxaparin 40 mg or identical placebo , given daily by subcutaneous injection until hospital discharge . Outcomes included total mortality at 90 days ( the primary outcome ) and 1 year , and occurrence in the VA hospital within 90 days of symptomatic deep venous thrombosis , pulmonary embolism , and major bleeding . RESULTS Only 7.6 % of hospitalized patients aged more than 60 years were eligible for the study , although a chart review had predicted 25 % . The principal exclusions were prior indication for anticoagulation , anticipated need for anticoagulation , contraindication to heparin , expected hospitalization less than 3 days , and " supportive/palliative care only " status . We r and omized 140 patients into each group , 28 % of target recruitment . The groups were well matched by age and comorbidities . Death occurred in 13 patients receiving enoxaparin and 14 patients receiving placebo at 90 days ( relative risk 0.93 , 95 % confidence interval 0.26 - 1.59 ) , and in 36 and 32 patients , respectively , at 1 year ( relative risk 1.13 , 95 % confidence interval 0.66 - 1.60 ) . Clinical thromboembolic events occurred in 5 patients receiving enoxaparin and 8 patients receiving placebo , and major bleeding occurred in 2 and 5 patients , respectively . CONCLUSIONS The pilot study indicated that the full study was not feasible . The decision to use prophylaxis pertains to only a small proportion of general medical patients hospitalized at VA medical centers , and this proportion is overestimated by chart review . The effect of low-dose heparin prophylaxis on clinical outcomes in hospitalized general medical patients remains uncertain Abstract Objective To determine the efficacy and safety of the anticoagulant fondaparinux in older acute medical in patients at moderate to high risk of venous thromboembolism . Design Double blind r and omised placebo controlled trial . Setting 35 centres in eight countries . Participants 849 medical patients aged 60 or more admitted to hospital for congestive heart failure , acute respiratory illness in the presence of chronic lung disease , or acute infectious or inflammatory disease and expected to remain in bed for at least four days . Interventions 2.5 mg fondaparinux or placebo subcutaneously once daily for six to 14 days . Outcome measure The primary efficacy outcome was venous thromboembolism detected by routine bilateral venography  along with symptomatic venous thromboembolism up to day 15 . Secondary outcomes were bleeding and death . Patients were followed up at one month . Results 425 patients in the fondaparinux group and 414 patients in the placebo group were evaluable for safety analysis ( 10 were not treated ) . 644 patients ( 75.9 % ) were available for the primary efficacy analysis . Venous thrombembolism was detected in 5.6 % ( 18/321 ) of patients treated with fondaparinux and 10.5 % ( 34/323 ) of patients given placebo , a relative risk reduction of 46.7 % ( 95 % confidence interval 7.7 % to 69.3 % ) . Symptomatic venous thromboembolism occurred in five patients in the placebo group and none in the fondaparinux group ( P = 0.029 ) . Major bleeding occurred in one patient ( 0.2 % ) in each group . At the end of follow-up , 14 patients in the fondaparinux group ( 3.3 % ) and 25 in the placebo group ( 6.0 % ) had died . Conclusion Fondaparinux is effective in the prevention of asymptomatic and symptomatic venous thromboembolic events in older acute medical patients . The frequency of major bleeding was similar for both fondaparinux and placebo treated patients BACKGROUND The American College of Chest Physicians addressed the dilemma of identifying optimal therapy for venous thromboembolism ( VTE ) prophylaxis and published their Fourth Consensus Conference on Antithrombotic Therapy in 1995 , with recommendations for prophylactic therapy . Despite these recommendations , appropriate VTE prophylactic therapy is underused . OBJECTIVES To examine routine practice s in the prevention of VTE in high-risk surgical patients and to determine the extent of adoption of grade A prophylactic therapies as recommended by the American College of Chest Physicians . METHODS Retrospective medical record review in 10 teaching or community-based hospitals located in the United States . Medical charts of 1907 patients were r and omly selected for review from the population of patients who underwent high-risk major abdominal surgery , total hip replacement , hip fracture repair , or total knee replacement between January 1 , 1996 , and February 28 , 1997 . RESULTS Of 1907 patients ,  VTE prophylaxis  was used in 89.3 % ; use was 93.7 % in each of the 3 orthopedic surgery groups and 75.2 % in the high-risk major abdominal surgery group . The percentage of patients receiving grade A therapy  was highest in the hip replacement group ( 84.3 % ) vs. the other groups ( knee replacement , 75.9 % ; hip fracture repair , 45.2 % ; abdominal surgery , 50.3 % ) . CONCLUSIONS The use of  grade A prophylaxis  was related to the type of surgery , with the highest use seen in total hip replacement and the lowest in hip fracture repair . One in 4 patients who underwent high-risk major abdominal surgeries failed to receive any form of VTE prophylaxis . Publication of consensus statements alone may be insufficient to ensure the incorporation of important new clinical information into routine practice A r and omised trial was undertaken in one hundred patients with heart failure and /or chest infection to determine whether low-dose subcutaneous heparin reduced the frequency of deep vein thrombosis ( DVT )  in the legs . Heparin , ( 5000 units 8 hourly ) significantly reduced the frequency of DVT , diagnosed by the125I-fibrinogen scan technique , from 26 to 4 per cent ( p < 0.01 ) . Heparin was started within 12 hours of admission to hospital and continued until the patient was fully mobile . Heparin did not cause bleeding problems except for a 20 per cent incidence of injection site bruising . We therefore recommend prophylaxis with low-dose subcutaneous heparin in patients with heart failure or chest infection who require more than three days bed rest Two hundred and seventy patients over 65 years were included in a placebo-controlled r and omized double-blind trial to determine whether a small dose of a low molecular weight ( LMW ) heparin prevents the occurrence of deep vein leg thrombosis ( DVT ) diagnosed by 125I fibrinogen scanning . LMW heparin ( 60 mg daily ) significantly reduced the frequency of DVT from 9 to 3 percent ( p = 0.03 ) . Adverse drug reactions did not differ significantly between the 2 groups , except for the injection site hematomas that were more frequent in the LMW heparin group . In conclusion , LMW heparin appears of value in preventing the occurrence of DVT in an unselected elderly in-patient population The utility of low-molecular-weight heparin ( LMWH ) in the prophylaxis of venous thromboembolic disease has been examined using the surrogate endpoint of venographically identified thrombi . The largest portion of these thrombi were asymptomatic calf-vein thrombi . The clinical relevance of this observation is a matter of debate . The present study is design ed to evaluate the impact of an LMWH on clinical ly important endpoints . The current study is a r and omized , prospect i ve , double-blinded , multicenter , multinational , controlled clinical trial comparing dalteparin with placebo in moderately high-risk hospitalized medical patients . A total of 3300 patients will be r and omized to receive either 5000 IU per day of dalteparin or placebo for 14 days . Patients will undergo appropriate evaluation for any symptomatic episodes and all patients will undergo a bilateral compression ultrasound ( CUS ) on day 21 to search for asymptomatic proximal thrombi . The primary endpoint is the combination of objective ly confirmed symptomatic deep vein thrombi ( DVT ) , fatal or non-fatal pulmonary emboli , all proximal DVT , and sudden death . This study will be the first study to examine clinical ly important endpoints in evaluating the effect of a LMWH in hospitalized medical patients . This study also is the first study to use CUS rather than venography in concordance with contemporary medical practice . This trial is thus design ed to address this important question in a clinical ly relevant manner OBJECTIVE To determine the cost and cost effectiveness of adding venous thromboembolism ( VTE ) prophylaxis with enoxaparin , a low-molecular-weight heparin , to st and ard care for acutely ill , hospitalized medical patients . METHODS A pharmacoeconomic model was developed to simulate the 6- to 14-day course of enoxaparin prophylaxis evaluated in the MEDENOX trial in a US healthcare setting . Clinical results as reported for the trial were applied to re source use and treatment costs in a US healthcare environment . The model projects hospital length of stay and cost for an acute medical admission from a third-party payer perspective , as well as costs for the course of enoxaparin . RESULTS VTE prophylaxis with enoxaparin would account for 1.2 % to 2.4 % of the cost of a hospital admission , with an additional $ 23 + /- $ 28 to $ 99 + /- $ 122 to complete the course of prophylaxis out of hospital . Incremental cost effectiveness of VTE prophylaxis relative to no prophylaxis ranges from $ 1249 to $ 3088 per VTE avoided . Venous thromboembolism prophylaxis appears to be a break-even intervention , with the cost recouped through avoided treatment , if the rate of treated VTE without prophylaxis is at least 3 - 4 % . DISCUSSION AND CONCLUSIONS The MEDENOX trial demonstrated that prophylaxis with enoxaparin substantially decreases the risk of VTE among acutely ill , hospitalized medical patients . Economic analysis indicates that this protection represents a small increase in current treatment costs . Prophylaxis is cost effective in terms of incremental cost per VTE avoided . Furthermore , there is a reasonable likelihood that the cost of prophylaxis will be offset by avoided future VTE treatment Background Hospitalised medical patients are at significant risk of venous thromboembolic disease through fatal pulmonary embolism ;  low-molecular-weight heparins have been proved efficient in preventing deep venous thrombosis in surgical and medical patients , but their effect on mortality in bedridden medical patients remains unknown . Methods In a multi-centre , r and omised , double-blind , placebo-controlled study , 2,474 consecutive patients aged over 40 years admitted to internal medicine departments in the last 24 h and unable to move alone were r and omised to receive 0.3 ml nadroparin ( 7,500 anti-Xa units ) or placebo for up to 21 days . The primary end-point was overall mortality at day 21 . Results There were no significant differences between the patients ’ characteristics . Overall mortality between the two groups was not statistically different [ 10.08 % ( 124 of 1,230 ) versus 10.29 % ( 128 of 1,244 ) , respectively , in the nadroparin and in the placebo groups ; relative risk reduction 0.02 , CI ( −0.27 , + 0.25 ) , P=0.89 ] . An autopsy was performed in 123 of the 252 patients who died ( 49 % ) . Pulmonary embolism was discovered at autopsy in 10 of 63 patients in the nadroparin group and in 17 of 60 in the placebo group [ relative risk reduction 0.38 , CI ( −0.27 , + 0.70 ) , P=0.13 ] . Conclusion Nadroparin does not have a significant effect on mortality in bedridden medical patients , based on the study results . The study provides no data suggesting that low-molecular-weight heparins might reduce the incidence of thromboembolic in- patients hospitalised for an acute medical disease BACKGROUND The efficacy and safety of thromboprophylaxis in patients with acute medical illnesses who may be at risk for venous thromboembolism have not been determined in adequately design ed trials . METHODS In a double-blind study , we r and omly assigned 1102 hospitalized patients older than 40 years to receive 40 mg of enoxaparin , 20 mg of enoxaparin , or placebo subcutaneously once daily for 6 to 14 days . Most patients were not in an intensive care unit . The primary outcome was venous thromboembolism between days 1 and 14 , defined as deep-vein thrombosis detected by bilateral venography ( or duplex ultrasonography ) between days 6 and 14 ( or earlier if clinical ly indicated ) or documented pulmonary embolism . The duration of follow-up was three months . RESULTS The primary outcome could be assessed in 866 patients . The incidence of venous 
    Output:
    
Implication s Anticoagulant prophylaxis substantially reduces the risk for venous thromboembolism in hospitalized medical patients .