Management of DVT (Deep Vein Thrombosis) Through Shaman Sneha and Shaman Aushadh

DVT is called as Phlebothrombosis. It is semisolid clot in the vein which has got high tendency to develop pulmonary embolism and sudden death. Most frequent site of thrombosis is calf region. A 60 yr male diagnosed with Deep vein thrombosis (DVT), complaining of pain and swelling on left leg (calf muscle) for 3 months, came in Panchkarma OPD in Chaudhary Brahm Prakash Ayurveda Charak Sansthan New Delhi. Pain and swelling increased with prolonged standing and walking. In Ayurveda Samhitas DVT is not mentioned as separate disease but the symptoms can be correlated with Siraj granthi or Siraja vata. Management: Case was managed according to general guidelines of Sotha, Rakta gata vata and Shiragata dosha. Shaman aushadh and Shaman sneha was given for 3 months. Result: Mild swelling and pain decreased in 15 days of medication. After 2 months, venous Doppler reports suggest partial thrombus noted in external iliac vein, deep femoral vein and popliteal vein shows resolution of thrombus as compared to previous Doppler wells score decreased up to 2

Deep Vein Thrombosis Complicating Recurrent Erythema Nodosum Leprosum

Recurrent erythema nodosum leprosum (ENL) is a type 2 leprosy reaction, which often poses a challenge for the treating physician. Patient may be non-ambulatory due to systemic symptoms like fever, body aches, joint pains, and painful skin lesions. Moreover, drugs like corticosteroids and thalidomide in refractory cases pose an increased risk of deep vein thrombosis (DVT). We have described a case who developed DVT in due course of the treatment.

DEEP VEIN THROMBOSIS – A SYSTEMATIC REVIEW

Deep vein thrombosis (DVT) is the formation of blood clots in deep veins, commonly the leg veins and the pelvic veins. DVT is a potentially fatal condition leading to increased mortality and morbidity if not diagnosed and treated promptly.Incidence is more prevalent in 60- 65 years of age because of increased pro-coagulant factors like factor VIII, factor VII, homocysteine, ?brinogen. With the increase in age the risk of DVT development increases exponentially.All bed ridden patients should receive sequential compression device therapy as primary DVT prophylaxis in the form of intermittent pneumatic compression device (IPCDs), graduated compression stocking (GCS), and the venous foot pump.The pharmacological agents used in the prophylaxis of DVT include low-molecular-weight heparins (LMWH), fondaparinux, Unfractionated heparin (UFH), new oral direct selective thrombin inhibitors and factor Xa inhibitors.The complications of DVT include development of Pulmonary embolism (PE) , Paradoxical emboli, Recurrent DVT, Post thrombotic syndrome. Approximately 4% individuals treated for DVT develop PE. It accounts for 10-12% mortality rate in hospitalized patients.The prevention and treatment must be upgraded continuously with evidence base strategies. This article aims at reviewing the clinical presentation, diagnostic and treatment modalities of DVT

Hemodynamic Study on the Relationship Between Collateral Circulation Caused by Iliac Vein Compression and Deep Venous Thrombosis / 医用生物力学

Objective To explore the relationship between the establishment of collateral circulation caused by iliac vein compression syndrom(IVCS) and the deep venous thrombosis (DVT). Methods Different types of ideal collateral circulation models and IVCS patient-specific models were numerically simulated using computational fluid dynamics (CFD) in combination with the blood stasis model. The relationship between blood retention and collateral types and cross-sectional area was studied, and the relationship with thrombosis was explored. Results Wall shear stress (WSS) at the distal end part of each ideal model was 0.3 Pa. After four cardiac cycles, the residual blood stayed at the stenosis and the distal end part for the lumbar ascending and pelvic type models, the old blood volume fraction (OBVF) varied with collateral cross-sectional areas, ranging from 5%-90% and 70%-80%, respectively. The OBVF of the coexistence model was above 80%. The WSS at the distal end part of the patient-specific model was 0.9 Pa, and the OBVF at the distal end part was 51.5%. Conclusions The stenosis and the distal end part are most prone to blood stasis, and closely related with DVT. The larger the collateral cross-sectional area, the more serious the blood stagnation. Blood stagnation of the coexistence model is higher compared with the model with lumbar ascending type and pelvic type.

Fatal pulmonary embolism after middle ear surgery: a case report

Pulmonary thromboembolism is a complication of underlying venous thrombosis. Factors contributing to thrombus formation include venous stasis, hypercoagulable state, immobilisation, surgery and pregnancy. Authors present the challenges authors faced in diagnosing pulmonary embolism in a post-operative patient. 35-year-old female with complaint of decreased hearing for 2 years along with tinnitus and giddiness was admitted for stapedectomy. She also gave history of dyspnoea and pedal oedema one month back for which she was hospitalized and underwent investigations which were normal. Patient was discharged as her clinical symptoms improved. On postoperative day 5, she developed sudden dyspnoea after getting up and walking a few steps. Dyspnoea along with falling saturation and bradycardia progressed to cardiopulmonary arrest. Intensive care was started. Bilateral lower limb venous doppler showed deep venous thrombosis. Clinical diagnosis of pulmonary embolism was made, and patient was lysed with Tenecteplase 30 mg. Echocardiography showed signs of resolution of embolism after lysis, but gradually patient deteriorated and developed cardiogenic shock. Intra-aortic balloon pump was inserted via right femoral artery and inotropic support was continued. However, patient’s condition worsened, and she developed cardiopulmonary arrest the next day and could not be revived. Prevention of pulmonary embolism is a major clinical problem for which prophylactic measures like early ambulation in post-operative periods, elastic stockings, graduated compressive stockings for bed ridden patients and preventive anticoagulation therapy in high risk patients should be considered.

Role of colour Doppler in evaluation of venous abnormalities of lower limb

Background: Venous abnormalities of lower limb are a fairly common cause of morbidity. Although clinical diagnosis is the cornerstone of the diagnosis of lower limb venous disease, Colour Doppler ultrasound has become the investigation of choice to confirm the diagnosis. This study evaluated the role of Colour Doppler ultrasound in various venous pathologies of the lower limb and the sonographic findings were correlated with surgical and clinical findings.Methods: 100 patients of all age groups of either sex presenting with clinically suspected entities affecting venous system of the lower limb were selected for this study.Results: Our study showed a definite male preponderance (65%) with an incidence of 41% in the age group of 21-40 years. Isolated varicose veins had an incidence of 58% followed by isolated deep vein thrombosis (DVT) (29%), varicose veins with thrombophlebitis (5%), DVT with thrombophlebitis (5%), DVT with varicose veins (2%) and hematoma (1%). The findings correlated with surgery and gave a sensitivity of 100%.Conclusions: Colour Doppler ultrasound is unique due to its feasibility, accessibility and cost effectiveness. Its dynamism is also exploited by various maneuvers done by the patients, radiologist and the machine parameters to bring about changes in blood flow to reach the exact diagnosis.

Enfermedad tromboembólica venosa: factores de riesgo y profilaxis en pacientes hospitalizados / Venous thromboembolic disease: risk factors and prophylaxis in hospitalized patients

Un alto porcentaje de pacientes hospitalizados puede presentar trombosis venosa profunda con sus corresponientes consecuencias. Objetivos: Determinar el riesgo y tratamiento profiláctico de enfermedad tromboembólica venosa (ETEV) en pacientes hospitalizados. Métodos:investigación de tipo observacional, transversal y multicéntrica. Se aplicó la escala de Caprini para identificar factores de riesgo en pacientes hospitalizados de cuatro hospitales del área Metropolitana de Caracas. Por otra parte, se aplicó una encuesta a médicos residentes y especialistas de las distintas sedes hospitalarias para determinar su conocimiento en profilaxis para ETEV. Resultados: Se registraron 851 pacientes hospitalizados con edad 48,6 + 19,3 años, con predominio del género masculino (59 %). Estaban en servicios quirúrgicos 489 pacientes (57,5 %) y servicios médicos 362 pacientes (42,5 %). Según la escala de Caprini 154 pacientes (18,1 %) estaban en riesgo moderado, y 642 pacientes (75,4 %) en riesgo alto. Recibieron tratamiento profiláctico 61 pacientes (7,7 %), siendo la medicación y la dosis adecuada solo en el 32,8 % de estos pacientes. En cuanto al conocimiento de ETEV, el 96,9 % de los médicos conoce la enfermedad, pero solo el 58,5 % reconoce la embolia pulmonar como parte de esta entidad. Solo el 49,2 % de los encuestados conoce o aplica escalas de riesgo para esta enfermedad. El tratamiento farmacológico es conocido por el 93,8 % de los médicos. Solo el 56,6 % de los médicos realiza seguimiento a los pacientes, siendo el lapso menor de 3 meses el más frecuente (40 %). Conclusiones: en nuestro estudio hay predominio de pacientes con alto riesgo para ETEV. El uso de profilaxis farmacológica es muy bajo. El conocimiento de escalas de riesgo no es adecuado(AU)

Venous thromboembolic disease is frequent in hospitalized patients.Objectives: To determine the risk and prophylactic therapy of venous thromboembolic disease (VTE) in patients with medical and surgical pathologies according to the Caprini scale. Methods: an observational, transversal and multicenter research was performed. The Caprini scale was applied to identify risk factors in medical and surgical hospitalized patients of four hospitals in the metropolitan area of Caracas. Also, a survey was applied to residents and specialists from the different hospitals to determine the knowledge about prophylactic treatment for VTE. Results: we registered 851 hospitalized patients with an age of 48,6 + 19,3 years, mainly men (59 %). There were 489 surgical patients (57,5 %) and 362 medical patients (42,5 %). According to Caprini risk scale 154 patients (18,1 %) were at middle risk and 642 patients (75,4 %) were at high risk. Prophylactic treatment was indicated in 61 patients (7,7 %), this treatment was adequate (doses and drug type) only in 32 % of these patients. About the ETV, 96,9 % of the medical doctors had knowledge of this illness, but only 58,5 % recognize pulmonary embolism as part of this entity. Only 49,2 % knows or applies risk scales for ETV. 56,6 % follows the patients, more frequently for less of 3 months (40 %). Conclusions: we found is a high predominance of moderate to high risk patients for ETV. Pharmacological prophylaxis was very low. ETV risk scales knowlegde is not adequate(AU)

Application Status and Biomechanical Research Progress of Vena Cava Filter / 医用生物力学

Vena cava filter was widely used in clinic to prevent pulmonary embolism in treating lower extremity deep venous thrombosis（DVT）. In this paper, application status of vena cava filter was reviewed, including the way of vena cava filter implantation, filter classification, indications of filter implantation and existing problems (contraindications and complications). The frontier issues concerning study on novel filters, such as the degradation filter and drug coated filter was also analyzed, and the hemodynamic research progress from domestic scholars in recent years about filter structure was briefly summarized. The research findings provide references for further optimization of filter structure and clinical application of vena cava filter.

Research on the Law of Prevention of Deep Vein Thrombosis (DVT) Based on Text Mining and Doctor-Patient Interaction Forum / 医学信息学杂志

Based on the doctor-patient interaction forum of Haodaifu Online,Xunyiwenyao and Youwenbida,taking advantage of the text mining technologies and methods such as Chinese word segmentation,data cleaning and filtering,word frequency statistics,semantic network map and visualization,extract and summarize the symptoms,causes,common drugs,complications,non-drug therapy and nursing method of Deep Vein Thrombosis (DVT),the paper verifies the availability of text mining method in exploring the prevention law and method of diseases and the feasibility of application of doctor-patient interaction Q&A network data source in medical research.

Effect of rivaroxaban in preventing deep venous thrombosis after large orthopedic operation of lower extremity / 药物评价研究

Objective To discuss the effect ofrivaroxaban in preventing deep venous thrombosis after large orthopedic operation of lower extremity.Methods Totally 80 patients after lower extremity of large orthopedic operation were selected,they were divided into two groups randomly.The patients in control group (39 cases) were sc injected with enoxaparin through.The patients in observation group (41 cases) were given rivaroxaban orally.The effect of rivaroxaban in preventing deep venous thrombosis after large orthopedic operation of lower extremity were evaluated by hemodynamic indexes,diagnosis index,and complications during 1 months follow-up.Results Before operation,there was no statistical significance on platelet,hemoglobin,and PT values between two groups.Compared with the value before operation,the value ofplatelet and hemoglobin had no significantly change after 3 d of operation.But the PT was increased (P ＜ 0.05).After 3 d of operation,there was no statistical significance on platelet and hemoglobin between two groups.But the PT value of observation was higher than that of control group (P ＜ 0.05).After 1 h operation,there was no statistical significance on D-dimer,Hcy,and hs-CRP between two groups.Compared with the value after 1 h of operation,the values of D-dimer,Hcy,and hs-CRP were decreased significantly (P ＜ 0.05).And the indexes of observation group were lower than those of control group (P ＜ 0.05).After 1 months of operation,although there was no statistical significance on complications between two groups,the incidence rate of secondary bleeding and DVT of control group was higher than that of the observation group.Conclusion The rivaroxaban could prevent DVT well,which is suitable for the anticoagulation therapy after lower extremity of large orthopedic operation with little influence on platelet and hemoglobin.It is worthy of clinical application.

The effect of Xuebijing injection on coagulation function and prevention of deep venous thrombosis in elderly fracture patients with mechanical ventilation / 中国基层医药

Objective To study effect of Xuebijing injection on coagulation function and prevention of deep venous thrombosis in elderly fracture patients with mechanical ventilation.Methods 60 patients were randomly divided into control group(30 cases) and Xuebijing group(30 cases).Xuebijing group received Xuebijing injection, besides physical therapy for prevention of deep venous thrombosis received by control group.Coagulation parameters and Lac at different time points,thrombosis incidence,hemorrhage incidence APACHE II score and 28 -day mortality were compared between the two groups.Results In Xuebijing group,PT,APTT,DD on d3 and Fg 48 on d5 had statistically significant differences compared with before treatment.PT,APTT on d3,d5 and DD on d5 were statistical-ly different compared with the control group(P <0.05).PLT,Lac,hemorrhage incidence and 28 -day mortality had no significant differences between the two groups.Thrombosis incidence in Xuebijing group was significantly lower than the control group(20.00% vs 3.33%) (χ2 =4.043,P =0.044,P <0.05).Both of APACHE II score were lower than before treatment,but the Xuebijing group was significantly decreased(t =5.48,P =0.000,P <0.05). Conclusion Xuebijing injection could improve coagulation function,and decrease thrombosis incidence in elderly fracture patients with mechanical ventilation.

The clinical forensic identification of deep vein thrombosis / 中国法医学杂志

Deep vein thrombosis is the common complication of trafifc injury , it is one of the dififculties of forensic identiifcation to identify disability grade and the relationship between injury and disease. When post-thrombotic syndrome happens, circulatory system and leg will be dysfunction, caused by the destruction of valve and venous wall and by the blockage of thrombus. The quality of life and working ability will be seriously affected. The impact of different types of deep vein thrombosis on human body was analysised after looking up relevant literatures, then it was discussed that the identiifcation of following questions including: the relationship between injury and disease, how to identify disability grade and it’s best time.

Deep vein thrombosis in arthroscopic surgery and chemoprophylaxis recommendation in an Asian population

<p><b>INTRODUCTION</b>There are currently no guidelines supporting the use of routine chemoprophylaxis to prevent deep vein thrombosis (DVT) in arthroscopic surgery. Studies and meta-analysis show opposing views on its routine use in arthroscopy. This study aimed to examine the incidence of DVT in a prospective cohort of knee arthroscopy and knee arthroplasty patients, and to analyse the risk factors contributing to DVT.</p><p><b>METHODS</b>All patients scheduled to undergo knee arthroscopy or arthroplasty over a two-year period were included. A standardised regimen of postoperative mechanical prophylaxis and rehabilitation was applied to all patients. Only patients who were postoperatively symptomatic were referred for ultrasonography. DVT incidence was calculated, and univariate and multivariate analyses of the risk factors were performed.</p><p><b>RESULTS</b>The overall incidence of DVT was 0.5% among the 1,410 arthroscopy patients and 3.1% among the 802 arthroplasty patients. The incidence of proximal DVT among the arthroscopy and arthroplasty patients was 0.4% and 1.1%, respectively. Multivariate analysis showed that age was the only significant predictor of DVT incidence. Using the receiver operating characteristic method, the cut-off age for the arthroscopy and arthroplasty patients was 52 years, while that for the arthroscopy patients only was 40 years (increased risk of DVT: 5.46 and 6.44 times, respectively; negative predictive value: 99.7% and 99.8%, respectively).</p><p><b>CONCLUSION</b>DVT incidence among Asian arthroplasty and arthroscopy patients remains low, even without chemoprophylaxis. Since age was found to be a significant risk factor for DVT, DVT prophylaxis can be considered for patients in high-risk age groups.</p>

Relationship between deep venous thrombosis and inflammatory cytokines in postoperative patients with malignant abdominal tumors

Deep venous thrombosis (DVT) is a common surgical complication in cancer patients and evidence that inflammation plays a role in the occurrence of DVT is increasing. We studied a population of cancer patients with abdominal malignancies with the aim of investigating whether the levels of circulating inflammatory cytokines were associated with postoperative DVT, and to determine the levels in DVT diagnoses. The serum levels of C-reactive protein (CRP), interleukins (IL)-6 and IL-10, nuclear transcription factor-κB (NF-κB) and E-selectin (E-Sel) were determined in 120 individuals, who were divided into 3 groups: healthy controls, patients with and patients without DVT after surgery for an abdominal malignancy. Data were analyzed by ANOVA, Dunnet's T3 test, chi-square test, and univariate and multivariate logistic regression as needed. The CRP, IL-6, NF-κB, and E-Sel levels in patients with DVT were significantly higher than those in the other groups (P<0.05). The IL-10 level was higher in patients with DVT than in controls but lower than in patients without DVT. Univariate analysis revealed that CRP, IL-6, NF-κB, and E-Sel were statistically associated with the risk of DVT (OR=1.98, P=0.002; OR=1.17, P=0.000; OR=1.03, P=0.042; and OR=1.38, P=0.003; respectively), whereas IL-10 had a protective effect (OR=0.94, P=0.011). Multivariate analysis showed that E-Sel was an independent risk factor (OR=1.41, P=0.000). Thus, this study indicated that an increased serum level of E-Sel was associated with increased DVT risk in postoperative patients with abdominal malignancy, indicating that E-Sel may be a useful predictor of diagnosis of DVT.

Effect of ulinastatin combined rivaroxaban on deep vein thrombosis in major orthopedic surgery

OBJECTIVE@#To explore the effect of ulinastatin (UTI) continuous infusion combined Rivaroxaban on the deep vein thrombosis in patients undergoing major orthopedic surgery.@*METHODS@#Forty-five patients undergoing major orthopedic surgery were randomly divided into three groups:ulinastatin continuous infusion (Uc) group, ulinastatin single injection (Us) group and control (C) group. All patients received patient-controlled intravenous analgesia (PCIA) after operation, and took Rivaroxaban 10 mg orally 12 hours after operation. Ulinastatin (5 000 U/kg) was given intravenously to both Uc and Us groups preoperatively. Group C was given isometric normal saline, group Uc was pumped UTI continuous intravenously at the end of surgery (10 000 U/kg) to 48 hours through PCIA pump. The values of hematocrit (HCT), thrombomodulin (TM), Interleukin (IL-6), thrombin-antithrombin complex (TAT), D-Dimer (D-D) were normally tested before surgery (T1), at the end of the surgery (T2), 12 hours (T3), 24 hours (T4) and 48 hours (T5) after surgery.@*RESULTS@#Compared with T1, there was an upward tendency in TM, IL-6, TAT, and D-D after operation in group C group (P0.05).@*CONCLUSIONS@#During the perioperative period, ulinastatin continuous infusion combined Rivaroxaban can correct blood hypercoagulability through different approaches in patients undergoing major orthopedic surgery.

Effect of ulinastatin combined rivaroxaban on deep vein thrombosis in major orthopedic surgery

Objective: To explore the effect of ulinastatin (UTI) continuous infusion combined Rivaroxaban on the deep vein thrombosis in patients undergoing major orthopedic surgery. Methods: Forty-five patients undergoing major orthopedic surgery were randomly divided into three groups:ulinastatin continuous infusion (Uc) group, ulinastatin single injection (Us) group and control (C) group. All patients received patient-controlled intravenous analgesia (PCIA) after operation, and took Rivaroxaban 10 mg orally 12 hours after operation. Ulinastatin (5 000 U/kg) was given intravenously to both Uc and Us groups preoperatively. Group C was given isometric normal saline, group Uc was pumped UTI continuous intravenously at the end of surgery (10 000 U/kg) to 48 hours through PCIA pump. The values of hematocrit (HCT), thrombomodulin (TM), Interleukin (IL-6), thrombin-antithrombin complex (TAT), D-Dimer (D-D) were normally tested before surgery (T1), at the end of the surgery (T2), 12 hours (T3), 24 hours (T4) and 48 hours (T5) after surgery. Results: Compared with T1, there was an upward tendency in TM, IL-6, TAT, and D-D after operation in group C group (. P0.05). Conclusions: During the perioperative period, ulinastatin continuous infusion combined Rivaroxaban can correct blood hypercoagulability through different approaches in patients undergoing major orthopedic surgery.

The use of routine chemoprophylaxis for deep vein thrombosis in all patients undergoing hip and knee replacements in rural population - whether it is justified.

Background: Deep vein thrombosis (DVT)/ pulmonary embolism (PE) are one of the most feared complications in patients undergoing joint replacements in western literatures. The exact incidence of DVT in Indians particularly rural population remains debatable. Also ways to prevent it in rural population is a dilemma for the orthopedic community. Hence this study was undertaken. Methods: We carried a prospective study of 135 cases of joint replacements i.e. 78 of total hip replacements and 57 of total knee replacements. None of the patients were given any form of chemoprophylaxis like low molecular weight heparin (LMWH). Strict monitoring was done. All patients underwent duplex ultrasonographic doppler assessment of both the lower limbs between the 4th-7th day and on 14th - 16th postoperative day. Only 5 out of 135 cases had DVT. Results: We observed that DVT developed more commonly following total hip replacement surgery (4 cases) as compared to total knee replacement (1 case). There was no mortality in our study. Conclusions: DVT following total joint replacements in rural Indian patients is not as common as reported in the Western literature. A high level of suspicion and close clinical monitoring is mandatory. The use of routine chemoprophylaxis in every patient is perhaps not justified. In future further more trials with a larger number of patients and at multiple centers would be required to confirm the findings of our study and to formulate guidelines to prevent DVT.

Deep Venous Thrombosis in Stroke Patients : An Analysis of the Rehabilitation Patient Database of the Japanese Association of Rehabilitation Medicine / The Japanese Journal of Rehabilitation Medicine

As a scholarly research activity using “the Japanese Association of Rehabilitation Medicine rehabilitation patient database”, we performed an analysis with the objective of clarifying the actual conditions of DVT in stroke patients. The subjects consisted of 345 stroke patients with DVT data from the “December 2010 version" of the database. In 9 of the 345 cases (2.6%), DVT complications were observed. No significant relevance among NIHSS, mRS, or the FIM score was found at the time of admission to hospital. In addition, no association with the number of days from the onset of PT (which is believed to be a related factor) and the onset of DVT was observed. For the acute condition change rate, the DVT complication group was observed to have a significantly high rate. Moreover, for the home recovery rate, the DVT complication group was observed to have a significantly low rate. Therefore, using only the severity of the condition at the time of admission and the length of the period until the commencement of rehabilitation, it is difficult to predict the onset of DVT, and it was shown that there is a danger of DVT occurring in any stroke patient. Furthermore, the acute condition change rate when DVT occurs as a complication is high. As a result, it is therefore necessary to be vigilant in the prevention and early diagnosis of DVT.

Prevention and treatment overview of deep vein thrombosis in perioperative period / 国际中医中药杂志

This article analyzed both the etiopathogenisis and high risk factors of DVT in patients of orthopaedics diseases. Furthermore, it explained both the prophylaxis and therapies of DVT from traditional Chinese medicine (TCM),western medicine, and combined traditional Chinese and western medicine point of view.

Influence of Low Molecular Weight Heparin on Perioperative Bleeding after Rear Operation of Thoracolumbar Spinal Bursting Fracture / 中国康复理论与实践

@#Objective To study the influence of bleeding after using low molecular weight heparin （LMWH） to prevent deep vein thrombosis (DVT) in patients with thoracolumbar spinal bursting fracture and spinal cord injury operated by rear internal fixation. Methods 120 cases were divided into the observation group (64 cases) and control group (56 cases). The observation group accepted hypodermic injection of LMWH to prevent DVT, while the control group did not. Results The volume of bleeding and blood transfusion, the change of red blood cell count (RBC) and hemoglobin were compared between two groups before and after operation. There is no statistical significance. Conclusion During the period of the operation of rear internal fixation, low molecular weight heparin cannot increase the bleeding and is safe to prevent deep vein thrombosis.