***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Venous thromboembolism is a serious complication following gynecologic surgery and is particularly common in patients with malignancy . A previous study of subcutaneous low-dose heparin given as one dose preoperatively and every 12 hours postoperatively failed to show a benefit in gynecologic oncology patients . In the present study , two more intense regimens of low-dose heparin were evaluated . Three hundred four patients were assigned r and omly to receive no prophylaxis ( controls ) , subcutaneous heparin 5000 units 2 hours before surgery and every 8 hours postoperatively ( low-dose heparin ) ( regimen I ) , or 5000 units heparin subcutaneously every 8 hours preoperatively ( between two and nine doses ) and every 8 hours postoperatively ( regimen II ) . All patients had thromboembolism surveillance with the fibrinogen uptake test and clinical evaluation . Eighty-four percent had a malignancy . Thromboemboli were diagnosed in 19 of 103 control patients , ten of 104 regimen I patients , and six of 97 regimen II patients , a statistically significant difference ( P < .008 ) . When compared with the control group , the study groups had no evidence of increased bleeding complications or alteration of laboratory coagulation indicators . ( Obstet Gynecol 75 : 684 , 1990 In a prospect i ve double-blind trial , low molecular weight ( LMW ) heparin ( KABI 2165 ) 5,000 U ( anti-Xa ) once daily was compared with conventional heparin 5,000 IU twice daily , both given subcutaneously , as regards prevention of postoperative deep venous thrombosis ( DVT ) in 52 patients undergoing major abdominal surgery . Radioactive fibrinogen uptake test ( FUT ) was used for DVT screening . DVT , diagnosed from positive FUT , developed in two patients from each group , but could be phlebographically confirmed in only one ( LMW ) case . No intergroup differences were found in peroperative blood loss or requirements for blood transfusion . Complications attributable to the prophylactic regimens were few . In the LMW-heparin group , the anti-Xa levels measured during operation showed considerable variation , the higher activities ( greater than 0.30 U/ml ) being nonsignificantly associated with increased blood loss . Studies with lower doses of LMW-heparin are recommended Lenalidomide plus dexamethasone is effective in the treatment of multiple myeloma ( MM ) but is associated with an increased risk of venous thromboembolism ( VTE ) . This prospect i ve , open-label , r and omized sub study of a phase 3 trial compared the efficacy and safety of thromboprophylaxis with low-dose aspirin ( ASA ) or low-molecular-weight heparin ( LMWH ) in patients with newly diagnosed MM , treated with lenalidomide and low-dose dexamethasone induction and melphalan-prednisone-lenalidomide consolidation . Overall , 342 patients who did not have clinical indications or contraindications to antiplatelet or anticoagulant therapy were r and omly assigned to receive ASA 100 mg/d ( n = 176 ) or LMWH enoxaparin 40 mg/d ( n = 166 ) . The incidence of VTE was 2.27 % in the ASA group and 1.20 % in the LMWH group . Compared with LMWH , the absolute difference in the proportion of VTE was 1.07 % ( 95 % confidence interval , -1.69 - 3.83 ; P = .452 ) in the ASA group . Pulmonary embolism was observed in 1.70 % of patients in the ASA group and none in the LMWH group . No arterial thrombosis , acute cardiovascular events , or sudden deaths were reported . No major hemorrhagic complications were reported . In previously untreated patients with MM receiving lenalidomide with a low thromboembolic risk , ASA could be an effective and less-expensive alternative to LMWH thromboprophylaxis BACKGROUND Ambulatory cancer patients at high-risk for venous thromboembolism ( VTE ) can be identified using a vali date d risk score ( Khorana score ) . We evaluated the benefit of outpatient thromboprophylaxis with dalteparin in high-risk patients in a multicenter r and omized study . METHODS Cancer patients with Khorana score≥3 starting a new systemic regimen were screened for VTE and if negative r and omized to dalteparin 5000units daily or observation for 12weeks . Subjects were screened with lower extremity ultrasounds every 4weeks on study and with chest CT at 12weeks . The primary efficacy endpoint was all VTE over 12weeks and primary safety endpoint was clinical ly relevant bleeding events over 13weeks . The study was terminated early due to low accrual . RESULTS Of 117 enrolled patients , 10 ( 8.5 % ) had VTE on baseline screening and were not r and omized . Of 98 r and omized patients  , VTE occurred in 12 % ( N=6/50 ) of patients on dalteparin and 21 % ( N=10/48 ) on observation ( hazard ratio , HR 0.69 , 95 % CI 0.23 - 1.89 ) . Major bleeding was similar ( N=1 ) in each arm but clinical ly relevant bleeding was higher in dalteparin arm ( N=7 versus 1 on observation ) ( HR=7.0 , 95 % CI 1.2 - 131.6 ) . There was no difference in overall survival . CONCLUSIONS Thromboprophylaxis is associated with a non-significantly reduced risk of VTE and significantly increased risk of clinical ly relevant bleeding in this underpowered study . The Khorana score successfully identifies patients with high incidence of VTE both at baseline and during treatment . Future studies should continue to focus on risk-adapted approaches to reduce the burden of VTE in cancer . TRIAL REGISTRATION clinical trials.gov identifier : NCT00876915 PURPOSE : Routine deep venous thrombosis prophylaxis is controversial in Asian patients , because deep venous thrombosis incidence was considered negligible . Because of recent reports of significantly higher incidences , a r and omized , controlled trial was conducted to assess the effectiveness and complications of enoxaparin prophylaxis ( low molecular weight heparins ) in major colorectal surgery . METHODS : Three hundred twenty consecutive patients were r and omly assigned to control or low molecular weight heparins groups . Patients in the low molecular weight heparins group were given perioperative enoxaparin starting 12 hours before surgery . The surgeon ( blinded ) assessed for difficulties related to possible enoxaparin administration . Independent blinded observers performed daily clinical assessment s and Doppler studies ( at the 3rd and 5th postoperative day ) . Deep venous thrombosis was confirmed by duplex ultrasound , and pulmonary embolism was confirmed by lung scans or postmortem examinations . RESULTS : Deep venous thrombosis developed in 5 of 169 ( 3 percent ) controls and 0 of 134 low molecular weight heparins patients ( P=0.045 ) . Three of the deep venous thrombosis patients had pulmonary embolism , which was fatal in one patient . The surgeons were unable to perceive any increased surgical difficulties in the low molecular weight heparins group . The bleeding-related complications were significantly higher in the low molecular weight heparins patients ( controls , n=3 ( 1.8 percent ) ; low molecular weight heparins , n=9 ( 6.7 percent ) ) . However , apart from one subdural hematoma and two abdominal hemorrhages needing re-exploration , which also occurred in one of the controls , these complications were minor bruises at the wounds , drains , or injection sites . CONCLUSION : Deep venous thrombosis prophylaxis is needed in Asian patients undergoing major colorectal surgery Summary : A r and omized controlled trial was undertaken comparing the efficacy and safety of low molecular weight ( LMW ) heparin ( Fragmin ) with sodium heparin for prophylaxis against postoperative thromboembolic disease after major gynaecological surgery . Women were r and omized to receive subcutaneous injections of 5,000 U of either once daily LMW heparin or twice daily sodium heparin . A total of 566 women were recruited , of whom 552 completed the study . Most women ( 461 ) had malignant disease and 430 of these underwent radical surgery . The remainder underwent major , but not radical surgery . There were 5 thromboembolic events in the LMW heparin group and 2 in the sodium heparin group , with no significant difference between these groups . No significant difference was found in the incidence of intraoperative or postoperative transfusion in the 2 groups . The decision of which heparin to use in routine practice can not be made on clinical grounds BACKGROUND Unfractionated heparin and the low molecular weight heparin , dalteparin , are used for prophylaxis against venous thromboembolism in patients undergoing craniotomy . These drugs were compared in a r and omized , prospect i ve pilot study comparing intermittent pneumatic compression devices plus dalteparin to intermittent pneumatic compression devices plus heparin . METHODS One hundred patients undergoing craniotomy were r and omly allocated to receive perioperative prophylaxis with subcutaneous ( SC heparin , 5000 units every 12 hours , or dalteparin , 2,500 units once a day , begun at induction of anesthesia and continued for 7 days or until the patient was ambulating . Entry criteria were age over 18 years , no deep vein thrombosis ( DVT ) preoperatively as judged by lower limb duplex ultrasound and no clinical evidence of pulmonary embolism preoperatively . Patients with hypersensitivity to heparin , penetrating head injury or who refused informed consent were excluded . Patients underwent a duplex study 1 week after surgery and 1 month clinical follow-up . All patients were treated with lower limb intermittent pneumatic compression devices . RESULTS There were no differences between groups in age , gender , and risk factors for venous thromboembolism . There were no differences between groups in intraoperative blood loss , transfusion requirements or postoperative platelet counts . Two patients receiving dalteparin developed DVT ( one symptomatic and one asymptomatic ) . No patient treated with heparin developed DVT and no patient in either group developed pulmonary embolism . There were two hemorrhages that did not require repeat craniotomy in patients receiving dalteparin and one that did require surgical evacuation in a patient treated with heparin . Drug was stopped in two patients treated with dalteparin because of thrombocytopenia . None of these differences were statistically significant . CONCLUSION There was no significant difference in postoperative hemorrhage , venous thromboembolism or thrombocytopenia between heparin and dalteparin . The results suggest that , given the small sample size of this trial , both drugs appear to be safe and the incidence of venous thromboembolism by postoperative screening duplex ultrasound appears to be low when these agents are used in combination with intermittent pneumatic compression devices Background Advanced pancreatic cancer ( APC ) , beside its high mortality , causes the highest rates of venous thromboembolic events ( VTE ) . Enoxaparin , a low molecular weight heparin ( LMWH ) , is effective in prevention and treatment of VTE . Some small studies indicated that this benefit might extend to patients with cancer and probably prolong survival due to independent mechanisms . We initiated this safety investigation to get feasibility information on intensified chemotherapy combined with LMWH in out patients with APC treated in 1st line . Methods The trial was a prospect i ve , open-label , single center investigation in out patients with inoperable pancreatic cancer who were treated with intensified first-line chemotherapy along with concomitant application of subcutaneous LMWH .  The combined chemotherapy consisted of gemcitabine 1 g/m2 ( 30 min ) , 5-FU 750 mg/m2 ( 24 h ) , folinic acid 200 mg/m2 ( 30 min ) , and Cisplatin 30 mg/m2 ( 90 min ) on day 1 and 8 ; q3w for the first 12 weeks ( GFFC ) followed by gemcitabine alone in patients without cancer progression . The simultaneous application of prophylactic enoxaparin started on day 1 of chemotherapy with a fixed dose of 40 mg daily . Statistical analyses were performed using R 3.01 with software package CMPRSK and SPSS software v19.0 . Results The investigation was stopped after recruitment of 19 patients . At this time 15 patients had completed the required 12 weeks of treatment . Based on 71 cycles of GFFC + enoxaparin ( median 4/pt [ range : 2–4 ] ) and 108 cycles of single-agent gemcitabine + enoxaparin ( median 4/pt [ range : 0–18 ] ) the cumulative frequency of NCI-CTC toxicities grade 3/4 was below 10 % . One case ( 5 % ) of a symptomatic non-lethal thromboembolic event was observed while receiving LMWH treatment . No severe bleeding event as defined in the protocol has been observed . The median overall survival was 10.05 [ 95 % CI : 8.67 - 18.14 ] months . Conclusions The addition 
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The meta-analyses found the following additional results : outcomes intraoperative blood loss ( MD -6.75 mL , 95 % CI -85.49 to 71.99 ; moderate-certainty evidence ) ; and postoperative drain volume ( MD 30.18 mL , 95 % CI -36.26 to 96.62 ; moderate-certainty evidence ) .In addition , the meta-analyses did not conclusively rule out either a beneficial or harmful effect of LMWH compared with Fondaparinux for the following outcomes : any VTE ( DVT or PE , or both ; RR 2.51 , 95 % CI 0.89 to 7.03 ; RD 57 more per 1000 , 95 % CI 4 fewer to 228 more ; low-certainty evidence ) , major bleeding ( RR 0.74 , 95 % CI 0.45 to 1.23 ; RD 8 fewer per 1000 , 95 % CI 16 fewer to 7 more ; low-certainty evidence ) , minor bleeding ( RR 0.83 , 95 % CI 0.34 to 2.05 ; RD 8fewer per 1000 , 95 % CI 33 fewer to 52 more ; low-certainty evidence ) , thrombocytopenia ( RR 0.35 , 95 % CI 0.04 to 3.30 ; RD 14 fewer per 1000 , 95 % CI 20 fewer to 48 more ; low-certainty evidence ) , any PE ( RR 3.13 , 95 % CI 0.13 to 74.64 ; RD 2 more per 1000 , 95 % CI 1 fewer to 78 more ; low-certainty evidence ) and postoperative drain volume ( MD -20.00 mL , 95 % CI -114.34 to 74.34 ; low-certainty evidence ) AUTHORS ' CONCLUSIONS : We found no difference between perioperative thromboprophylaxis with LMWH versus UFH and LMWH compared with fondaparinux in their effects on mortality , thromboembolic outcomes , major bleeding , or minor bleeding in people with cancer .
There was a lower incidence of wound hematoma with LMWH compared to UFH