Deep Vein Thrombosis (DVT) AUTHORS: Nancy Skinner, RN, C, CCM Peter Moran, RN, C, BSN, MS, CCM

Transcription

1 Deep Vein Thrombosis (DVT) AUTHORS: Nancy Skinner, RN, C, CCM Peter Moran, RN, C, BSN, MS, CCM

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3 CMAG CASE MANAGEMENT ADHERENCE GUIDELINES VERSION 1.0 DEEP VEIN THROMBOSIS (DVT) Guidelines from the Case Management Society of America for improving patient adherence to DVT medication therapies August Case Management Society of America Presented by Radio Gate International, Inc. Aston, PA Supported by a sponsorship from sanofi-aventis, U.S., LLC.

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5 DEEP VEIN THROMBOSIS Table of Contents Page Title v Introduction 1 Deep Vein Thrombosis 37 Appendix 1: Resources and Web Links 43 Appendix 2: References iii

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7 Introduction In 2004, the Case Management Society of America (CMSA) introduced a set of guiding principles and associated tools that were developed to aid in the assessment, planning, facilitation and advocacy of patient adherence. Entitled the Case Management Adherence Guidelines (CMAG), these concepts were designed to advance the goal of creating an environment of structured interaction, based on patient-specific needs that would encourage patient adherence with all aspects of the prescribed treatment plan. Over the ensuing years, thousands of healthcare professionals attended CMAG educational workshops throughout the United States. CMAG Workbooks that comprehensively detail all CMAG tools and supportive knowledge were made available in multiple languages, including English, Spanish, French and Korean. Subsequently, CMAG was recognized as the primary educational standard for case managers that present a collaborative approach for affecting patient-specific health behavior change and for advancing patient adherence. This addendum to the basic CMAG program utilizes the primary concepts of motivational interviewing, assessment of health literacy and implementation of adherence improvement tools to promote adherence in the patient who is diagnosed with or at risk for developing deep vein thrombosis (DVT). Case managers and other healthcare clinicians and professionals who work with these patients will find the tools and resources found in this addendum specifically targeted to address understanding of the disease as well as adherence challenges and assessments that are specific to DVT. CMSA continues to provide CMAG educational workshops throughout the United States. Copies of the CMAG manual and this Disease State Chapter addendum may be downloaded at no cost at v

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9 Deep Vein Thrombosis DEEP VEIN THROMBOSIS In this volume we will review the following: Venous Adherence Tools The The Key Motivational thromboembolism (VTE) including common risk factors and available prophylactic measures and associated treatment protocols. issues including adherence to evidence-based guidelines and patient adherence to the prescribed treatment plan. that are available to seamlessly facilitate an efficient and effective transition of care from one treatment environment to an another. role the case manager plays in improving patient adherence and transitioning care. importance of patient education and the availability of tools to advance the appropriate delivery of that education. quality indicators associated with the prevention of VTE. and knowledge tools that encourage adherence in the patient who is at risk for or being treated for VTE. 1

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11 Deep Vein Thrombosis DEEP VEIN THROMBOSIS CONDITION BACKGROUND AND DESCRIPTION Disease Prevalence Venous thromboembolic disease (VTE) is a term encompassing deep vein thrombosis (DVT) and pulmonary embolism (PE), or a combination of both. DVT is a common vascular condition that arises from the formation of a blood clot within the deep veins of the circulatory system. PE occurs when a segment of that thrombosis detaches or separates from the vein wall, travels through the bloodstream, and lodges in the pulmonary artery. DVT is not a rare disease. Approximately 900,000 people are diagnosed with a VTE annually, 1 with one in 20 Americans experiencing a DVT during their lifetime. 2 However, due to the silent nature of the disease and because the general public often underestimates the true incidence of DVT, it may be difficult to gauge the absolute impact of this disease state. Some epidemiological studies have estimated an annual incidence of 80 cases per 100, The absolute risk of DVT development in hospitalized patients who do not receive prophylaxis is considerably higher, with incidence varying from 10 to 80%. 4 Although a diagnosis of DVT can be associated with high morbidity, the most dangerous consequence of VTE is PE. As many as 10% of all hospital deaths can be attributed to pulmonary embolism, 5 making PE the most common cause of preventable hospital death in America. 6 PE is the leading cause of death associated with childbirth and is the direct cause of death for approximately 300,000 people every year. 7,8,9 In addition to compromising the health of the American public, the consequences of VTE strain the financial viability of our healthcare system. The diagnosis and treatment of this disease state generates costs that exceed $15.5 billion in America alone. 10 Because the threats associated with VTE can impact the cost, as well as the quality and the outcomes of care, it is essential that all members of the healthcare delivery team, including case/care managers and disease managers, understand the threat that VTE presents. COMMONLY RECOGNIZED SIGNS AND SYMPTOMS In many patients, DVT is clinically silent. It can occur without any overt signs or symptoms, or present with symptoms that are so subtle that even the patient may not be aware that the condition exists. In other cases, symptoms may be identified but no one physical symptom or sign is sufficiently accurate to establish a diagnosis of DVT. When signs and symptoms are apparent, the intensity and variety of symptoms are directly related to the degree of obstruction of venous outflow and inflammation of the vessel wall. 3

12 CMAG The common signs and symptoms of DVT include sudden swelling of one extremity, redness or discoloration of the skin, warmth of the affected area, pain that may exacerbate with exercise but not disappear with rest, low-grade fever, and tachycardia. Homans sign is a rapid discomfort in the calf muscles on forced dorsiflexion of the foot with the knee straight. Although this may be suggestive of DVT, it is not consistently present in all patients with DVT and may be indicative of other disease in the lower extremities. Pulmonary embolism is a life-threatening situation because the formation of an embolism may block a major pulmonary vessel. This can cause cardiogenic shock followed by circulatory failure and death. Over 60% of pulmonary emboli are clinically undiagnosed, and death may occur in as short a time as 30 minutes. 11 Symptomatic PE is often characterized by shortness of breath, hypoxia, tachycardia, pleuritic chest pain, hemoptysis, hypotension, fatigue, or peripheral circulatory failure. COMPLICATIONS OF VTE Pulmonary embolism is the most immediate and significant complication of DVT. PE has been detected in over 50% of all patients with a documented diagnosis of DVT. Over 80% of patients with confirmed diagnosis of PE have been found to have asymptomatic DVT. 12,13 While PE is the greatest cause of mortality associated with DVT, other complications can also arise, potentially compromising the health of millions of Americans each year. The two most noteworthy of these complications are recurrent DVT and postthrombotic syndrome. Up to 30% of patients may experience a recurrent DVT within eight years of an initial diagnosis. 14 This pattern of recurrence is important because it may contribute to the development of PE and cause additional damage to venous valves, prompting chronic venous insufficiency. Many patients with recurrent DVT require prolonged if not lifelong therapy to manage this disease. Post-thrombotic syndrome (PTS) is another significant complication of VTE that occurs in approximately 29% of patients with symptomatic DVT within 8 years of the initial event. 15,16 PTS commonly develops secondary to venous valve damage, which precipitates venous hypertension and may compromise the integrity of the vascular system within the lower extremities. 17 The primary symptoms of PTS include pain, varicose veins, edema, venous ectasia, induration, and ulceration. Chronic ulceration and impaired mobility due to debilitating pain may cause disability and negatively impact quality of life. DIAGNOSIS OF DVT AND PE Clinical risk, suspicion, and probability will alert practitioners to the possibility of VTE. The diagnosis is then confirmed by clinical exam and the results of diagnostic tests. The identification of VTE risk is generally associated with pathophysiologic factors that are based on a hypothesis presented by Rudolph 4

13 Deep Vein Thrombosis Virchow over 100 years ago. Virchow believed that the formation of a thrombosis was the direct result of an interaction of factors, including venous stasis, vascular endothelial damage and hypercoagulability of the blood. 18 Conditions and predisposing factors that are representative of those three aspects of Virchow s research include the following: 19,20 Previous DVT or family history of thrombosis Coagulation abnormalities, including positive factor V Leiden, positive prothrombin 20210A, elevated serum homocysteine, protein C deficiency, protein S deficiency, or excessive plasminogen activator inhibitor Age over 40 (incidence increase with age) Obesity (BMI > 25 kg/m 2 ) Immobility, such as bed rest or sitting for long periods of time Major trauma (< 1 month) Acute spinal cord injury (< 1 month) Recent surgery (< 1 month) Stroke (< 1 month) Limb trauma and/or orthopedic procedures Limb immobilized by plaster cast (< 1 month) Previous or current cancer Cancer therapy (hormonal, chemotherapy, or radiotherapy) Smoking Serious lung disease including pneumonia (< 1 month) Abnormal pulmonary function (COPD) Indwelling central venous catheter Inflammatory bowel disease Acute infection (< 1 month) Cardiac dysfunction including heart failure (< 1 month) Severe sepsis Hypertension Hyperlipidemia Nephrotic syndrome Autoimmune disease, including systemic lupus erythematosus Myeloproliferative disorders 5

14 CMAG Varicose veins Swollen legs (current) Hormone therapy or oral contraceptives Pregnancy or postpartum period History of unexplained stillborn infant, recurrent spontaneous abortion (>3), premature birth with toxemia, or growth restricted infant The importance of several of these risk factors is more comprehensively detailed as follows: Cancer. In 38% of concomitant cancer and DVT, the DVT is detected first. The relative risk of cancer is 19 times higher for patients younger than 50 years who have had a DVT. 16% of patients with confirmed PE are diagnosed with cancer within 2 years, 21 and one in every seven hospitalized cancer patients will die due to a PE. 22 Prior DVT. Patients with a history of a prior DVT are five times more likely to develop a subsequent DVT. 23 Age. The rate of VTE may be twice as common in patients between the ages of 50 and 81. Heart Failure. There is a 38.3 times greater risk of VTE observed in patients with a Left Ventricular Ejection Fraction ( LVEF) <20%. 24 Chronic Obstructive Pulmonary Disease. Up to 25% of hospitalized patients with this respiratory condition are estimated to have a DVT. 25 In addition to disease specific conditions, clinical interventions and treatment also may increase the risk of VTE formation. For surgical patients, the incidence of DVT is affected by the preexisting factors listed above and by factors relating to the procedure itself, including the site, technique, and duration of the procedure; the type of anesthetic; the presence of infection; and the degree of postoperative immobilization. 26 Venous thromboembolism risk in surgical patients who do not receive prophylaxis is estimated to be: Hip fracture, 40% to 60% Total hip replacement, 40% to 60% Total knee replacement, 40% to 60% Urologic surgery, 15% to 40% General and gynecologic surgery, 15% to 40% 6 Neurosurgery, 15% to 40% 27 Note: The above detailed list is a partial list of common risk factors for VTE. Healthcare professionals are advised to consider other risk factors and conditions that may predispose the patient to VTE.

15 Deep Vein Thrombosis Use of Risk Assessment Tools In addition to evaluating clinical probability, risk factors, and the presenting symptoms, pretest probability scoring tools may be useful in assisting the physician to advance the accuracy of a diagnosis of DVT. Although a number of scoring tools are available, the two tools that are included in this document are the Hamilton Score (Table 1) and the Modified Wells Score. 28 The Modified Wells score (Table 2) includes a ten component tool that predicts either the unlikely- or likely-probability of DVT. The Hamilton score has seven components and can also be utilized to predict the unlikely- or likely-probability of disease presence. When used in conjunction with blood assays, these tools may be useful in determining the necessity for further evaluation or testing in ambulatory emergency room patients. 29 Table 1 Hamilton Score Characteristics Score Plaster immobilization of lower limb 2 Active malignancy (within 6 months or current) 2 Strong clinical suspicion of DVT by emergency department physicians and no other diagnostic possibilities 2 Bed rest (>3 days) or recent surgery (within 4 weeks) 1 Male sex 1 Calf circumference >3 cm on affected side (measured 10 cm below tibial tuberosity) 1 Erythema 1 Note A score of 2 represents unlikely possibility for deep venous thrombosis (DVT); a score of 3 represents likely probability for DVT. Source: Am J Roentgenol 2006 American Roentgen Ray Society Reprinted with permission from the American Journal of Rosentgenology. 7

16 CMAG Table 2 Modified Wells Score Clinical Characteristics Score Active cancer (patient receiving treatment for cancer within previous 6 months or currently receiving palliative treatment) 1 Paralysis, paresis, or recent plaster immobilization of lower extremities 1 Recently bedridden for 3 days or more, or major surgery within previous 12 weeks requiring general or regional anesthesia 1 Localized tenderness along distribution of deep venous system 1 Entire leg swollen 1 Calf swelling at least 3 cm larger than that on asymptomatic side (measured 10 cm below tibial tuberosity) 1 Pitting edema confined to symptomatic leg 1 Collateral superficial veins (nonvaricose) 1 Previously documented DVT 1 Alternative diagnosis at least as likely as DVT 2 Note A score of 2 indicates that probability of deep venous thrombosis (DVT) is likely; a score of <2 indicates that probability of DVT is unlikely. Source: Am J Roentgenol 2006 American Roentgen Ray Society Reprinted with permission from the American Journal of Rosentgenology. Diagnostic Tests Other diagnostic evaluations that are utilized to establish a confirmed diagnosis of DVT may include D-dimer assay, duplex ultrasound, impedance plethysmography, MRI, and/or contrast venography. A D-dimer assay, which detects fibrin degradation in the blood, is commonly used as a rapid initial test for the presence of VTE. Clinical research appears to support the hypothesis that a negative D-dimer assay rules out DVT in patients with low- to moderate-risk and a Wells DVT score of less than In patients with a positive D-dimer assay and all patients with a moderate- to high-risk of DVT (Wells DVT score >2), further diagnostic testing is recommended. 31 It should be noted that since D-dimer assays present a low specificity for DVT, the value of this test should be limited to ruling out rather than confirming the diagnosis of a DVT. Compression ultrasound is a noninvasive examination that is sensitive and specific for the diagnosis of DVT above the knee. Sonography is less sensitive for detecting thromboses in the deep veins of the calf because it is not always possible to visualize all three of the major veins in this region. If no DVT is detected but symptoms or suspicion persists, the ultrasound examination should be repeated after a week to detect formerly occult calf vein thrombus that might have propagated into the deep popliteal or femoral veins. 30 8

17 Deep Vein Thrombosis Sonography can be an excellent diagnostic tool but it does have some limitations, including operator error, an inability to distinguish old clots from a newly forming clot, a lack of accuracy in detecting DVT in the pelvis or the small vessels of the calf, and a lack of accuracy in detecting DVT in the presence of obesity or significant edema. Impedance plethysmography (IPG) is a noninvasive technology that measures electrical resistance of blood volume in the leg. Although it is used extensively in other countries to detect DVT, recent studies have questioned its efficacy in confirming the presence of proximal DVT. 32 Magnetic Resonance Imaging (MRI) is highly sensitive and specific in confirming thrombosis in the pelvic veins. Although the costs associated with MRI are significant and the test may not be appropriate for patients with pacemakers or other metallic implants, it can be an effective diagnostic option for some patients. Contrast venography detects thrombi in both the calf and the thigh and can confirm or exclude a diagnosis of DVT when other objective testing is not conclusive. But with value comes controversy. Some physicians view venography as an invasive and expensive procedure that is either contraindicated or nondiagnostic in more than 25% of patients. Additionally, venography may be the primary cause of DVT in 3% of patients who undergo this diagnostic procedure. Although venography was once considered the gold standard for diagnosis of DVT, today it is more commonly used in research environments and less frequently utilized in clinical practice. Patients who present with signs and symptoms suggestive of DVT that cannot be confirmed through comprehensive diagnostic testing should be retested within three to five days. Diagnostic testing to confirm or exclude the presence of a pulmonary embolism commonly includes chest radiograph, arterial blood gas measurements, and an electrocardiogram. Although ventilation/perfusion scans were once utilized to identify the presence of a PE, CT pulmonary angiography combined with CT venography of lower extremity is now recommended for patients with symptoms of pulmonary embolism to detect emboli in the lung and to screen for DVT. 9

18 CMAG PREVALENT TREATMENT MODALITIES The primary treatment goals for a confirmed diagnosis of DVT or PE include prevention of additional thrombus formation, extension and embolism; restoration of valve patency; preservation of lower extremity venous valve function; and prevention of post-thrombotic syndrome. Physicians utilize a variety of treatment modalities to assist them in achieving these goals, including anticoagulants, thrombolytics, and surgical intervention. Initiation of anticoagulation to address the treatment of DVT may include the administration of unfractionated heparin (UFH), a low molecular weight heparin, a pentasaccharide (fondaparinux), or warfarin. When UFH therapy is initiated, it may be initially administered intravenously at a dose of 5000 U with subsequent infusions of 1250 U per hour. Another option for UFH therapy is for a weight-adjusted regimen of 80IU/kg bolus, followed by 18U/kg/h. Dosing is usually adjusted to an activated partial thromboplastin (aptt) prolongation corresponding to plasma heparin levels of 0.3 to 0.7 IU/ml anti XA activity by the amidolytic assay. 33 UFH also may be delivered subcutaneously. When SC UFH is utilized, an initial IV bolus of 5,000 U of unfractionated heparin is followed by a SC dose of 17,500 U bid on the first day. When patients are receiving SC heparin, the aptt should be drawn 6 hours after the morning administration, and the dose of UFH should be adjusted to achieve a 1.5 to 2.5 prolongation. 34 UFH therapy should be continued for at least five days. The American College of Chest Physicians (ACCP) Guidelines recommend that warfarin therapy be initiated on the first day of therapy and titrated to an international normalized ratio (INR) that is stable and > 2.0. Most patients continue to receive warfarin for a period of three to six months. Heparin is contraindicated in patients with a known sensitivity and in patients with subacute bacterial endocarditis, severe liver disease, hemophilia, active bleeding, and a history of heparin-induced thrombocytopenia. Digoxin, nicotine, tetracycline, and antihistamines decrease the effectiveness of the drug, while NSAIDS, aspirin, dextran, dipyridamole, and hydroxychlorine may potentiate its effects. Low molecular weight heparins (LMWH) offer more predictable pharmacokinetics and a greater bioavailability than UFH; therefore, the ACCP Antithrombotic Guidelines has recommended initial treatment with LMWH SC once or twice daily over UFH. 35 Three low molecular weight heparins have received FDA approval for the treatment of DVT. Tinzaparin sodium (Innohep ) is approved for the treatment of acute symptomatic DVT with or without PE when administered in conjunction with warfarin. 36 The safety and effectiveness of tinzaparin were established in hospitalized patients. Dalteparin (Fragmin ) is indicated for the extended treatment of symptomatic venous thromboembolism to reduce the recurrence of VTE in patients with 10

19 Deep Vein Thrombosis cancer. 37 Enoxaparin (Lovenox ) is indicated for the inpatient treatment of acute DVT with and without PE, when administered in conjunction with warfarin sodium, and is indicated for the outpatient treatment of acute DVT without PE when administered in conjunction with warfarin sodium. Because enoxaparin offers indications for both the inpatient and outpatient treatment of DVT, the following discussion of LMWH as an appropriate and cost-effective treatment for DVT will be limited to that specific antithrombotic agent. Use of Enoxaparin: Inpatient and Outpatient When provided in an inpatient environment, enoxaparin is administered subcutaneously at a weight-based dosage of 1 mg/kg every 12 hours, or 1.5 mg/kg daily. Concurrent warfarin therapy is begun on the first day of treatment. Enoxaparin therapy should be continued for at least five days and is discontinued when a therapeutic level of warfarin has been achieved (INR is stable and > 2). 38 For an initial diagnosis of DVT, warfarin may be continued for three to six months or longer as determined by a risk-benefit analysis. In instances of a recurrent DVT, warfarin therapy may become a lifelong treatment. LMWH therapy has been shown to be safe and effective in both the acute care and home environments. Clinical studies have shown no documented increase in the risk of recurrence of thrombosis as compared to heparin. Those studies have also indicated that the probability of hemorrhage, thrombocytopenia, and osteoporosis is diminished when compared to traditional therapies. Additionally, no concurrent laboratory testing is required to confirm the effectiveness of this form of anticoagulant therapy. When enoxaparin is provided in an outpatient environment, the continuing care plan may include services offered by an outpatient anticoagulation clinic, coordination of care facilitated by the attending physician s office, or the administration of therapy in the home by a home health nurse, the patient, or the patient s support system. The course of outpatient anticoagulant therapy generally includes the administration of enoxaparin at a recommended subcutaneous dosage of 1 mg/kg every 12 hours. Concurrent warfarin therapy also will be initiated and titrated to achieve an INR of 2 to 3. Enoxaparin therapy should be continued for a minimum of 5 days. Although the average duration of administration is 7 days, up to 17 days of Lovenox therapy has been administered in controlled clinical trials. 39 Outpatient enoxaparin therapy is contraindicated in patients who are unable to receive outpatient heparin therapy because of associated comorbid conditions, experience a concurrent symptomatic PE, have a history of two or more prior occurrences of DVT or PE, have elevated liver function tests, or have a hereditary bleeding disorder. Outpatient therapy with enoxaparin provides clinical outcomes comparable to traditional inpatient antithrombotic therapies. Additionally, outpatient treatment with enoxaparin has been shown to be more cost effective. A cost analysis of outpatient enoxaparin therapy detailed a decrease in acute care length of stay from 4.5 days to 0.97 days, resulting in a cost reduction of $2,300 per patient

20 CMAG Use of Fondaparinux: Inpatient Another option for the inpatient treatment of DVT is fondaparinux (Arixtra ). Fondaparinux is a pentasaccharide that is indicated for the treatment of acute DVT when administered in conjunction with warfarin. It is also indicated for the treatment of acute pulmonary embolism when administered in conjunction with warfarin and when initial therapy is administered in the hospital. 41 In patients with acute symptomatic DVT and in patients with acute symptomatic PE, the recommended dose of fondaparinux is 5 mg (body weight <50 kg), 7.5 mg (body weight kg), or 10 mg (body weight >100 kg) by subcutaneous injection once daily. Treatment with fondaparinux should be continued for a least 5 days and until a therapeutic oral anticoagulant effect is established. Concomitant treatment with warfarin should be initiated as soon as possible, generally on the first day of treatment. The usual duration of fondaparinux therapy is 5 to 9 days. Pharmacologic Precautions Each LMWH and/or pentasaccharide cannot be used interchangeably (unit for unit) with heparin or other low molecular weight heparins as they differ in manufacturing process, molecular weight distribution, anti-xa and anti-iia activities, units, and dosage. Each of these medicines has individual instructions for use and should be utilized within established guidelines. 42,43,44 Although unique, each of these medications carries a precautionary statement regarding the concurrent use of LWMH s, heparinoids or fondaparinux therapy, and neuraxial anesthesia. Specific information regarding this precaution and other potential adverse effects of therapy are included in the prescribing information for each medication. Table 3 outlines treatment protocols for different conditions using each of these medications. Table 3 Low Molecular Weight Heparin or Pentasaccharide Indications for VTE Treatment Therapeutic Indication Dalteparin Enoxaparin Tinzaparin Fondaparinux VTE Treatment (Fragmin ) (Enoxaparin ) (Innohep ) (Arixtra ) Treatment of acute DVT with or without PE with transition to warfarin YES YES YES Outpatient treatment of acute DVT without PE with transition to warfarin YES Treatment of acute PE with transition to warfarin YES Extended treatment of VTE (proximal DVT and/or PE) to reduce the recurrence of VTE in patients with cancer YES 12

21 Deep Vein Thrombosis Antithrombotic therapy should be used judiciously in patients with renal impairment. Renal dysfunction can increase drug exposure; therefore, any patient with renal compromise should be closely monitored for the signs and symptoms of bleeding. Because each LMWH is unique and cannot be used interchangeably, individual instructions for use in patients with renal insufficiency should be carefully considered. In patients with severe renal impairment (creatinine clearance <30 ml/min), it is recommended that the prescribed dosage of enoxaparin be adjusted for therapeutic and prophylactic dosage ranges. Specific information regarding enoxaparin dosing regimens for patients with severe renal impairment is included in the prescribing information offered for the drug. Prescribing information for tinzaparin recommends that it be used with care in patients with renal insufficiency. For patients with renal impairment receiving dalteparin, dosing reductions may be appropriate. And, patients who have severe renal compromise are not appropriate for pentasaccharide (fondaparinux) therapy. In patients with a confirmed diagnosis of DVT, the ACCP recommends the use of an elastic compression stocking with a pressure of 30 to 40 mm Hg at the ankle for two years after an episode of DVT. 38 The consistent use of compression stockings may reduce the incidence of post-thrombotic syndrome as a complication of DVT. Thrombolytics may be an important component of the treatment plan if circulation to the affected extremity is blocked by a large thrombus or if a PE has compromised the patient s respiratory function. While these clot busters generally provide a prompt resolution of symptoms, they do not inhibit the development of additional thrombi or affect the rate of pulmonary embolism. For this reason, anticoagulant therapy is generally prescribed as an adjunct to thrombolytic intervention. The disadvantages of thrombolytic therapy include a higher cost than traditional anticoagulant therapy and, more importantly, a greater risk for hemorrhage, including the possibility of a fatal intracerebral hemorrhage. Non-Pharmacologic Interventions In some patients, the placement of an inferior vena cava filter is utilized to prevent migration of any thrombus. The goal of treatment is to capture any thrombus that is traveling through the circulatory system before that thrombus negatively impacts pulmonary function. Retrievable filters may be indicated when there is a contraindication to anticoagulation therapy, such as recent hemorrhage or impending surgery in patients with newly diagnosed proximal DVT. 45 It is important to note that these filters can increase the risk of recurrent DVT. 13

22 CMAG Surgical intervention may also be considered when anticoagulation or thrombolytic therapy is contraindicated. Thrombectomy may be utilized to advance venous patency and promote valvular function and is generally reserved for patients who experience a massive ileofemoral vein thrombosis or pulmonary embolism. Although the treatment of pulmonary embolism generally reflects the common treatment modalities associated with deep vein thrombosis, the provision of anticoagulant therapy to address PE is usually initiated within an acute care environment. The Patient s Role in Their Treatment Patients can contribute to the attainment of desired treatment outcomes by initiating a variety of lifestyle changes. Patients should maintain adequate hydration by drinking water or juice and avoiding alcoholic beverages. ACCP Guidelines recommend ambulation as tolerated for patients with a confirmed diagnosis of DVT. 46 Some physicians believe that ambulation prevents venous stasis and extension of the thrombus. Patients also should avoid any activity or behavior that inhibits the free flow of blood within the lower extremities, including restriction of movement or wearing tight-fitting clothing. 47 Patients might wish to explore long-term lifestyle modifications, including smoking cessation, achieving a BMI that is 25kg/m 2, maintaining a normal blood pressure, achieving glycemic control, and managing lipid levels. PROPHYLAXIS AND RISK STRATIFICATION The most important intervention associated with VTE treatment is prevention of the disease before it can occur. Yet studies have demonstrated that the overall compliance rate with ACCP Prophylaxis Guidelines needs improvement. One retrospective study of over 123,000 at risk medical and surgical patients demonstrated compliance rates of only 13.3%. Potential reasons for noncompliance with those guidelines included omission of prophylaxis, inadequate duration of prophylaxis, and prescription of an ineffective form of anticoagulant therapy. 48 Another study that assessed the rate of VTE prophylaxis in medical patients reported that on average, only 33% of medical patients received prophylaxis that reflected current ACCP guidelines and an average of 44% received no prophylaxis at all. 49 To close the gap that exists between evidence-based guidelines and reported prophylaxis patterns in current clinical practice, it is essential that all healthcare professionals understand the risk factors for VTE development, consistently identify patients who are at risk, and take the necessary steps to reduce that risk. Most patients who experience acute or chronic disease or experience a surgical intervention will exhibit at least one identifiable risk factor for the development of DVT. Healthcare providers usually employ one of two strategies to quantify risk in those development patients. 14