Role of Physical Therapists in the Management of Individuals at Risk for or Diagnosed With Venous Thromboembolism: Evidence-Based Clinical Practice Guideline

Action statement profile

Aggregate Evidence Quality: Level I

Benefits: Decreased likelihood of LE DVT and/or PE and/or PTS

Risk, Harm, Cost: Injuries from falls

Benefit-Harm Assessment: Preponderance of benefit

Value Judgments: Physical therapists should advocate for mobility in all situations due to the evidence on the benefits of activity and risks associated with inactivity and bed rest except when there could be a risk of harm (eg, emboli depositing in the pulmonary system).

Intentional Vagueness: None

Role of Patient Preferences: As the evidence for risks associated with inactivity is strong and with little associated risk of mobility in the absence of thromboembolism, patients should be educated regarding the benefits of mobility and encouraged to maintain mobility as much as possible to decrease the risk of adverse outcomes.

Exclusions: None

Summary of evidence

Reduced mobility is a known risk factor for VTE, yet the quantity and duration of the reduced mobility that defines degree of risk for VTE are not known.^19–21 Significant variability exists in the literature regarding reduced mobility and the resulting risk for VTE.²² Patients who were ambulatory were found to be at increased risk for developing a VTE with a standing time of 6 or more hours (odds ratio [OR]=1.9) or resting in bed or a chair (OR=5.6).²³ Likewise, a significant correlation exists between loss of mobility status for 3 or more days and the presence of LE DVT on duplex ultrasound.²⁴

When additional risk factors for VTE are present in an individual who has any reduction in mobility, the risk for VTE is significantly increased. Increased age serves as an example. One study of hospitalized patients older than 65 years found reduced mobility to be an independent risk factor for VTE. The risk increased based on the degree of immobility, and relative risk scores were derived according to the degree of immobility (Tab. 5).^19,25 The OR risk was found to be higher in older patients with more severe limitation of mobility (bed rest versus wheelchair) and when the loss of mobility was more recent (<15 days versus >30 days).

Recent national guidelines have associated reduced mobility with increased risk for VTE.^20,26 The National Institute for Health and Care Excellence (NICE) guidelines present strong recommendations for the need to regard patients undergoing surgery and patients with trauma as at an increased risk of VTE. When patients undergo surgery with an anesthesia time of greater than 90 minutes or if the surgical procedure involves the pelvis or lower limb and anesthesia time is greater than 60 minutes, the risk is much greater. Individuals who are admitted acutely for surgical reasons or admitted with inflammatory or intra-abdominal conditions also are at high risk for developing a VTE. These same guidelines emphasized the need to identify all individuals who are expected to have any significant reductions in mobility to be at risk for VTE and to mobilize them as soon as possible.²⁰ The American College of Chest Physicians (ACCP) guidelines emphasize prevention of VTE in patients not undergoing surgery by incorporating nonpharmacological prophylaxis measures, including frequent ambulation, calf muscle exercise, and sitting in the aisle and mobilizing the lower extremities when traveling (Grade 2C recommendations).^26,27

Previously, when individuals were diagnosed with an LE DVT, they were placed on bed rest due to the concern that ambulation would cause clot dislodgment and lead to a potentially fatal PE. However, a meta-analysis compiled data from 5 randomized controlled trials (RCTs) on more than 3,000 patients and concluded that early ambulation following diagnosis of an LE DVT was not associated with a higher incidence of a new PE or progression of LE DVT compared with bed rest.²⁸ Rather, there was a lower incidence of new PE and overall mortality in those patients who engaged in early ambulation. Similar findings, as well as more rapid resolution of pain, were reported in a systematic review that included 7 RCTs and 2 prospective observational studies.²⁹ The importance of mobility is further discussed in key Action Statement 8.

In summary, mobility should be encouraged in patients while in the hospital and when discharged to prevent the complications associated with immobility. In addition, mobility is recommended for those diagnosed with VTE once therapeutic anticoagulant levels have been reached (see Action Statement 8).

Action statement profile

Aggregate Evidence Quality: Level I

Benefits: Prevention or early detection of LE DVT

Risk, Harm, and Cost: Adverse effects of prophylaxis interventions

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: None

Intentional Vagueness: Physical therapists should work within their health care system to determine specific algorithms or risk assessment models (RAMs) to use.

Role of Patient Preferences: None

Exclusions: None

Summary of evidence

The Guide to Physical Therapist Practice states that the physical therapist examination is a comprehensive screening and specific testing process leading to diagnostic classification or, as appropriate, to a referral to another practitioner.³⁰ Understanding the factors that place individuals at risk for a VTE is important for all physical therapists. During the patient interview, physical therapists should ask questions and review the medical history to determine whether the patient is at risk for LE DVT. Risk factors include previous venous thrombosis or embolism, age, active cancer or cancer treatment, severe infection, oral contraceptives, hormonal replacement therapy, pregnancy or given birth within the previous 6 weeks, immobility (bed rest, flight travel, fractures), surgery, anesthesia, critical care admission, central venous catheters, inherited thrombophilia, and obesity. The relationship between particular risk factors and presence of LE DVT has been found through retrospective and prospective studies and identified as having support from level I evidence in other CPGs.^19,31–34

The need for all health care providers to screen for risk of LE DVT through system-wide approaches has been highlighted by the US Agency for Healthcare Research and Quality,³⁵ the Finnish Medical Society,³¹ and the Scottish Intercollegiate Guidelines Network,³⁶ and such screening is strongly recommended by each of these groups. Furthermore, the importance of screening was strongly supported in a 2008 multinational cross-sectional study of patients from more than 350 hospitals across 32 countries. The findings revealed that 39.5% of patients at risk for VTE were not receiving appropriate prophylaxis.³⁷ Hospital-wide strategies were recommended to assess patients' VTE risk and to monitor whether those at risk received appropriate prophylaxis.

To facilitate and standardize the process of screening for risk within health care systems and across professions, RAMs should be considered.^36,38 Risk assessment models use a checklist to determine whether risk factors for LE DVT are present and each risk factor is assigned a point value. If a set point level is reached, the patient is considered at an increased risk, and more aggressive prophylactic interventions can be used. There are numerous examples of RAMs in the literature, including the Padua score for assessing VTE risk in hospitalized patients,³⁹ the IMPROVE VTE RAM,⁴⁰ the Autar DVT Risk Assessment Scale,⁴¹ and the Geneva Risk Score.⁴² None have been shown to be superior to others through direct comparisons, and, for this reason, the GDG cannot recommend a single RAM. It is more important that physical therapists work within their health care system to understand and even help develop an overall VTE protocol that uses an agreed-upon tool for VTE risk assessment.

In summary, given the risks and harms associated with a VTE and the relationship of VTE incidence to the presence of risk factors, physical therapists should screen for VTE risk. These results should be communicated with the rest of the health care team.

Action statement profile

Aggregate Evidence Quality: Level I

Benefits: Prevention of LE DVT

Risk, Harm, Cost: None to minimal

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: None

Intentional Vagueness: None

Role of Patient Preferences: Patients may or may not choose to adhere to preventive measures. There is a role for having shared decision making with regard to their priorities.

Exclusions: None

Summary of evidence

For individuals who are at risk for LE DVT, preventive measures should be initiated immediately, including education regarding leg exercises, ambulation, proper hydration, mechanical compression, and assessment regarding the need for medication referral.

Education is a key factor in risk reduction of VTE and should be provided for patients who are at elevated risk for LE DVT and for their families. Documentation of the patient's understanding of these concepts also should be included.⁴³ Topics that should be included in this education program for these patients and their families are: risk factors for DVT, possible consequences of DVT, interventions to decrease the risk of DVT, signs and symptoms of DVT and importance of seeking medical help if DVT is suspected, importance of follow-up monitoring, importance of treatment adherence, and medication issues (eg, regimen, adverse side effects and interactions, dietary restrictions).⁴⁴

Immobilization is one of the primary risk factors for VTE and is a problem for patients in the home and in acute care settings and long-term care facilities. Immobility, as it relates to residents in long-term care facilities, is defined by the presence of at least one of the following: lower limb cast, bedridden, bedridden except for bathroom privileges, recent decreased ability to walk at least 3.1 m (10 ft) for a least 72 hours, and inability to walk at least 3.1 m (10 ft).⁴⁵ Patients who are limited to a chair or bed greater than half the day during waking hours are considered at elevated risk for VTE. The acuteness and severity of the immobility determines the elevated risk level of developing VTE.¹⁹

As immobility also occurs with long-distance travel, travelers on planes for greater than 2 to 3 hours are also at increased risk for LE DVT. The ACCP²⁷ recommends that such travelers ambulate frequently, perform calf muscle exercises, sit in an aisle seat, and use below-the-knee compression stockings with at least 15 to 30 mm Hg compression (2C recommendation).

Action statement profile

Aggregate Evidence Quality: Level I

Benefits: Prevents LE DVT without increasing the risk of bleeding

Risk, Harm, Cost: Improper fit can lead to skin irritation, ulceration, or interruption of blood flow.

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: None

Intentional Vagueness: Specific types of mechanical compression were not recommended. Physical therapists should work within their health care system to develop institution-specific protocols.

Role of Patient Preferences: Ease of use, comfort level, and ability to operate mechanical compression equipment properly should be evaluated with each patient.

Exclusions: Patients who have severe peripheral neuropathy, decompensated heart failure, arterial insufficiency, dermatologic diseases, or lesions may have contraindications to selective mechanical compression modes.

Summary of evidence

The influence of mechanical compression on LE DVT or PE prophylaxis was examined in 7 systematic reviews.^46–52 The populations included patients who were in postoperative recovery from a variety of surgical procedures, with or without pharmacological prophylaxis. Also included were airline travelers of varying VTE risk levels. These studies supported that GCS used alone significantly decreased the incidence of LE DVT or PE and that this mechanical compression method provided additional benefit when combined with other prophylactic methods. Although GCS was the method of mechanical compression in all 7 of these publications, the descriptive features of the GCS were inconsistent.

Screening to identify VTE risk is essential and will identify which, if any, mechanical compression method is appropriate to implement. In the CPG of the Japanese Circulation Society for PE and LE DVT prevention, elastic stockings or IPC, IPC or anticoagulation, and anticoagulation plus IPC or elastic stockings are recommended for postoperative patients with elevated risk.⁵³ The Institute for Clinical Systems Improvement guidelines for VTE prophylaxis recommend that if contraindications exist for both low-molecular-weight heparin (LMWH) and low-dose unfractionated heparin (UFH) and there is high risk for VTE but not high risk for bleeding, fondaparinux or low-dose aspirin or IPC be used.⁴³ One example would be someone with a history of heparin-induced thrombocytopenia (HIT). Intermittent pneumatic compression or GCS are recommended for patients who are acutely or critically ill and who are bleeding or are at high risk for major bleeding, until bleeding risk decreases, at which time pharmacological thromboprophylactic methods can be substituted.^38,54

A systematic review of 6 RCTs looked at patients at high risk for VTE who underwent various surgical procedures to assess the effectiveness of IPC combined with pharmacological prophylaxis versus single modality usage.⁵⁵ Combining IPC with an anticoagulant (eg, LMWH) was more effective in VTE prevention than either IPC or anticoagulant use alone, which is consistent with the CPG recommendation offered by the Japanese Circulation Society.

In summary, there is substantial supportive evidence for the use of mechanical compression methods for patients with medical conditions or undergoing surgery,^36,56–60 prolonged air-flight travelers,^6,47,49 and patients in long-term care facilities.⁴⁵ For those people at increased risk for VTE, the use of GCS or IPC, with or without anticoagulation therapy, is considered to be beneficial. The evidence is inconsistent, however, in describing the optimal protocols for use of GCS, elastic stockings, or IPC. Potential for rare circulatory compromise with the use of GCS (ie, knee or thigh length) warrants proper fitting and careful monitoring of skin condition by the patient and physical therapist.

Action statement profile

Aggregate Evidence Quality: Level II

Benefit: Early intervention and prevention of adverse effects of LE DVT

Risk, Harm, Cost: None

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: Although the Wells criteria for LE DVT are recommended by this GDG, there are other tools that may be preferred by other interprofessional teams.

Intentional Vagueness: None

Role of Patient Preferences: None

Exclusions: None

Summary of evidence

The major signs and symptoms of LE DVT include pitting edema, pain, tenderness, swelling, warmth, redness or discoloration (erythema), and prominent superficial veins.^36,45,61,62 The presence of these signs and symptoms should raise the suspicion of an LE DVT, but they cannot be used alone in the diagnostic process.^31,61 The likelihood of LE DVT should be established through use of a standardized tool. This recommendation is supported by numerous CPGs^26,36,61,63 and a meta-analysis.⁶² A standardized tool uses the presence of clinical features of an LE DVT to determine the likelihood that an LE DVT is present and guides the selection of the most appropriate test to diagnose an LE DVT. Physical therapists should use a standardized tool as part of their examination process when signs and symptoms of LE DVT are present. The results of the assessment should then be communicated with the medical team.

The Wells criteria for LE DVT are the most commonly used tool to determine likelihood of LE DVT (Tab. 6).^21,64 Originally, the Wells criteria for LE DVT used a 3-tier risk stratification of low, moderate, and high. A score of 3 or greater was high risk, a score of 1 to 2 was moderate risk, and a score of 0 or below was low risk. In a study of 593 patients, 16% had an LE DVT. When the rate of LE DVT was examined in each stratification level, the rates were 3% (95% confidence interval [CI]=1.7%, 5.9%), 16.6% (95% CI=12%, 23%), and 74.6% (95% CI=63%, 84%) for low, moderate, and high risk, respectively. Other studies have shown a clear distinction in the rate of LE DVT among the 3 risk stratification levels.^62,65 A 2014 systematic review showed that, as the score on the Wells criteria increased, so did the likelihood of an LE DVT.⁶⁶ This relationship has held up across multiple subgroups of patients, including outpatients, inpatients, those with malignancy, and patients grouped by sex and previous history of an LE DVT.

In 2003, the Wells criteria for LE DVT were modified to a 2-stage stratification (ie, LE DVT likely or LE DVT unlikely), and a history of previous LE DVT was added to the tool.⁶⁷ Reducing the model to 2 levels made it easier to use and did not compromise patient safety when used in conjunction with a D-dimer test. Individuals with 2 or more points were categorized as likely, and those with less than 2 points were categorized as unlikely. In a study of 1,082 outpatients, 27.9% (95% CI=23.9%, 31.8%) of those classified as likely had a proximal LE DVT or a PE. Of those patients classified as unlikely, 5.5% (95% CI=3.8%, 7.6%) had a proximal LE DVT or a PE.

Beyond the Wells criteria for LE DVT, other risk stratification tools have been developed, but there are limited comparison studies among the tools. One example is the Oudega rule, developed for primary care providers. When compared to the Wells criteria for LE DVT, it has similar effectiveness.^68,69

The Wells criteria for LE DVT have a long and well-supported history of successfully stratifying risk or likelihood of LE DVT across patient populations and practice settings; therefore, the GDG recommends this tool for risk stratification. Physical therapists should advocate for its use with their interdisciplinary team and determine the best way to communicate the results and risks.

Action statement profile

Aggregate Evidence Quality: Level I

Benefit: Risk stratification can ensure proper diagnostic testing is completed

Risk, Harm, Cost: None

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: None

Intentional Vagueness: None

Role of Patient Preferences: None

Exclusions: None

Summary of evidence

Once the Wells criteria for LE DVT are complete, medical testing can be ordered by the medical team to diagnose or rule out an LE DVT. The selection of which medical test is beyond the scope of physical therapist practice, but there is benefit in understanding why tests are selected and how results guide the diagnostic process. If a patient is classified as unlikely to have an LE DVT, the overwhelming recommendation is for the medical team to order a D-dimer test over other more costly and invasive tools.^{26,31,43,44,70} Within the referenced CPGs, the evidence is rated as level I, with grade of A to B for the recommendation. The D-dimer test is a measure of the breakdown or degradation of cross-linked fibrin, which increases in the presence of a thrombosis. In patients with an LE DVT–unlikely classification and a negative D-dimer test, fewer than 1% have an LE DVT, and studies report sensitivity in the upper 90% to 100%.^71–73 These patients need no further testing and can be considered safe to mobilize.^{26,31,36,43,70}

Although the D-dimer test has high sensitivity, it has poor specificity. A positive D-dimer test does not indicate a definite LE DVT. A range of conditions, such as older age, infections, burns, and heart failure, can lead to an elevated D-dimer test, and hospitalized individuals have a high rate of false positives when the D-dimer is used for a suspected LE DVT.⁷⁴ When a patient who is LE DVT–unlikely has a positive or high D-dimer level, further testing is necessary. Most guidelines recommend a duplex ultrasound to confirm an LE DVT.^26,43,44,63 There is some debate on the type of ultrasound that is ordered, but this factor is beyond the focus of these guidelines. If the ultrasound confirms an LE DVT, medical treatment should be initiated and mobilization postponed. If the ultrasound is negative, the patient is safe to mobilize.

A patient rated as LE DVT–likely should immediately undergo a duplex ultrasound.^26,31,44,63 Individuals in the DVT–likely category will test positive on the D-dimer test, so the D-dimer test has little value. If the ultrasound is negative, the physical therapist should consider the patient safe to mobilize. If the ultrasound is positive, the physical therapist should defer mobility until medical treatment has achieved therapeutic levels.

In summary, the results of the Wells criteria for LE DVT should guide the selection of medical testing. Following the results of the medical testing, the physical therapist can then make a decision about when it is safe to mobilize the patient.

Action statement profile

Aggregate Evidence Quality: Level V

Benefit: Decreased risk of a PE in patients who are adequately anticoagulated

Risk, Harm, Cost: Risk of bleeding with anticoagulation, risk of adverse effects with restrictions in inactivity, and cost of new anticoagulants may be prohibitive in those with inadequate pharmacy insurance coverage.

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: Intentional vagueness. This CPG has provided therapeutic ranges for anticoagulants that have been provided by the manufacturers due to the limited evidence beyond this. Although the recommendation strength is weak based on scientific evidence, the GDG considers it prudent to follow the manufacturer's recommendations.

Role of Patient Preference: Patients should be informed of the importance for continuing anticoagulation upon discharge from the hospital as different anticoagulants require monitoring, cost, and modification of diet and bleeding risk.

Exclusions: None

Summary of evidence

Anticoagulants are the primary defense used to prevent and treat an LE DVT and consequent PE or PTS. Contrary to popular belief, anticoagulants do not actively dissolve a blood clot but instead prevent new clots from forming. Although anticoagulants are often referred to as blood thinners, they do not actually thin the blood. This class of drugs works by altering certain chemicals in the blood necessary for clotting to occur. Consequently, blood clots are less likely to form in the veins or arteries, and yet continue to form where needed. Although anticoagulants do not break down clots that have already formed, they do allow the body's natural clot lysis mechanisms to work normally to break down clots that have formed.

Once an LE DVT is diagnosed, anticoagulant therapy is initiated, most commonly with LMWH. Anticoagulant therapy will help to stop an existing clot from getting larger and prevent any new clots from forming. In addition, LMWH has been shown to stabilize an existing clot and resolve symptoms through the drug's anti-inflammatory properties, making a clot less likely to migrate as an embolus.

A patient diagnosed with an LE DVT is at risk of developing a PE; therefore, mobility is contraindicated until intervention is initiated to reduce the chance of emboli traveling to the lungs.^75–79 According to the ACCP guidelines on antithrombotic therapy, anticoagulation is the main intervention and should be initiated as soon as possible (level I, strong evidence).^26,43,44,61 If the patient is at a high risk for bleeding, the primary contraindication to anticoagulation, then medications may not be prescribed. Therefore, prior to initiating mobility out of bed, a physical therapist should review all medications the patient has been prescribed and verify that the patient is taking an anticoagulant. The physical therapist should next consult with the medical team regarding appropriateness of mobility. Although physical therapists do not play a role in recommending the anticoagulant of choice, they should identify which anticoagulant the patient has been prescribed and date and time of the first dose. This approach will assist the physical therapist in determining when the patient has reached a therapeutic dose, and consequently, when mobility may be initiated safely.

The current options for anticoagulation include UFH, LMWH, Coumadin (Bristol-Myers Squibb, New York, New York) (warfarin), fondaparinux, and oral thrombin or Xa inhibitors (eTable). Most patients with a confirmed diagnosis of LE DVT or PE are prescribed a form of LMWH or fondaparinux (both given with subcutaneous injections).^31,44,61 Low-molecular-weight heparin is principally used to treat any LE DVT below the knee, at thigh level, and more proximal thrombi.³¹ It is the anticoagulant of choice for pregnancy and for active cancer and the primary choice of physicians for treatment of VTE in the outpatient or home setting due to ease of use and low incidence of side effects.^31,43,61 Low-molecular-weight heparin is used in most cases except when a patient has renal dysfunction or a creatinine clearance less than 30 mL/min. Concomitant Coumadin use may be started and provided for 3 days, with subsequent international normalized ratio (INR) values being determined. Most individuals will continue with their initial anticoagulant (LMWH or fondaparinux) for 3 to 6 months for the first episode of diagnosed thrombosis. If Coumadin is given concomitantly, they will likely be removed from the initial anticoagulant and continued on Coumadin for 3 to 6 months.^44,80

Anti-Xa levels can be used to monitor LMWH. However, evidence does not support the use of anti-Xa assay levels for predicting thrombosis and bleeding risk.⁸¹ Pharmacokinetic studies on LMWH report that maximum anti-factor Xa and antithrombin IIa activities occur 3 to 5 hours after subcutaneous injection of LMWH.⁸² The optimal therapeutic anti-Xa levels for treatment are 0.5 to 1.0 U/mL. Due to the fact that LMWH is excreted primarily by the kidneys, increased bleeding complications have been reported when LMWH is used in patients with renal insufficiency and other populations. Therefore, precautions for bruising and bleeding with physical therapy interventions should be taken when LMWH is used in patients with kidney injury or dysfunction, patients in extreme weight ranges, patients who are pregnant, and neonates and infants.⁶³

Unfractionated heparin is indicated for individuals with high bleeding risk (eTable) or renal disease. Patients with established or severe renal impairment are defined as those with an estimated glomerular filtration rate of less than 30 mL/min/1.73 m². Unfractionated heparin is often prescribed and dosed to achieve therapeutic levels quickly. Lower speeds of infusion are usually given in acute coronary syndromes, whereas higher speeds of infusion are given with VTE. Several institutions have transitioned from monitoring heparin with anti-factor Xa levels instead of activated partial thromboplastin time (aPTT) due to influencing factors that can alter aPTT levels.⁸³ One study has shown anti-Xa detects therapeutic levels faster than aPTT (patients with UFH achieved therapeutic anticoagulation in approximately 24 hours compared with patients monitored with aPTT, which averaged 48 hours).⁸³ Patients with a documented PE, including those who are hemodynamically unstable, are often prescribed UFH, and similar aPTT monitoring should be reviewed by the physical therapist seeing the patient.⁴⁴

Coumadin is usually not the first medication choice for anticoagulation due to the length of time to achieve peak therapeutic levels. Coumadin is typically introduced on day 1 during administration of another anticoagulation, usually with LMWH or UFH.⁶¹ The loading anticoagulant (LMWH or UFH) is continued for at least 5 days until an INR greater than 2.0 is achieved for at least 24 hours, prior to discontinuing the loading anticoagulant, and first episodes of VTE should be treated with a target INR range of 2.5.⁸⁰ The UFH or LMWH is often discontinued when the INR is greater than 2.0.⁶¹

Fondaparinux (Arixtra, GlaxoSmithKline, Research Triangle Park, North Carolina) is similar to LMWH, is monitored using anti-Xa assays, and is often used when individuals need treatment or prophylaxis for VTE but have a history of HIT.⁴³ The maximal therapeutic dosage is reached in approximately 2 to 3 hours.^43,79 Fondaparinux also is used for thromboprophylaxis in patients with medical and surgical conditions, as is LMWH.⁶³

Both UFH and LMWH are associated with HIT, defined as an immune-mediated reaction to heparins. Heparin-induced thrombocytopenia can occur in 2% to 3% of patients treated with UFH and in approximately 1% of patients treated with LMWH.⁴³ Heparin-induced thrombocytopenia will result in a paradoxical increased risk for venous and arterial thrombosis, and this risk lasts approximately for 100 days following initial reaction. Therefore, patients with a history of HIT should not receive either LMWH or UFH with subsequent VTE.^43,84 Treatment for anticoagulation in individuals with HIT involves using fondaparinux or other thrombin-specific inhibitors such as lepirudin or argatroban. Indicators of HIT are: skin lesion reaction at injection site, systemic reaction to a bolus administration of heparin, and 50% decrease in platelet count from normal ranges while on heparin. Indicators of delayed-onset HIT are: thromboembolic complications 1 to 2 weeks after receiving the last dose of LMWH or UFH, and mild-to-moderate thrombocytopenia.

Mobility decisions with an individual receiving Coumadin are based on the initial anticoagulant and not Coumadin. Concern regarding exercise and out-of-bed activity should be raised for elevated INRs greater than 4.0 when patients are taking warfarin.⁸⁵ If the INR is between 4.0 and 5.0, resistive exercises should be avoided, with participation in light exercise only (eg, rating of perceived exertion ≤11) due to increased risk of bleeding.⁸⁵ Ambulation should be restricted if gait is unsteady to prevent falls.⁸⁵ The likelihood of bleeding rises steeply as INR increases above 5.0.^86–88 If the INR is greater than 5.0, discussion should be held with the referring physician regarding patient safety. When the INR is greater than 6.0, the medical team should consider bed rest until the INR is corrected.^85,86 In most cases, INRs can be corrected within 2 days.⁸⁵ When reversal of anticoagulation is needed for surgery and the patient is taking Coumadin, fresh frozen plasma is the choice to replace the anticoagulation.⁸⁶

New oral anticoagulant drugs (direct thrombin inhibitors and direct factor Xa inhibitors) are growing in popularity due to their ease of use (no laboratory monitoring, no adverse dietary or other drug interactions) and their rapid time to peak therapeutic levels. In addition, there appears to be less risk of cerebral hemorrhage, as occurs in vitamin K antagonists.⁸⁶ Rivaroxaban (Xarelto, Janssen Pharmaceuticals Inc, Titusville, New Jersey), dabigatran (Pradaxa, Boehringer Ingelheim Pharmaceuticals Inc, Ridgefield, Connecticut), and apixaban (Eliquis, Bristol-Myers Squibb Co) are the 3 new oral anticoagulant drugs in use at this time (refer to eTable for dosage, method of delivery, and peak therapeutic-level time frames). The new oral anticoagulant drugs are recommended by the American Academy of Orthopaedic Surgeons for hip and knee arthroplasty but have not been tested or recommended for individuals who have cancer, are undergoing treatment for cancer, or are pregnant.⁸⁹ There are concerns regarding reversal of anticoagulation with these medications. However, reconstructed recombinant factor Xa or activated charcoal have both been proposed as antidotes.^89,90 The time for reversal is the amount of time to eliminate the drug from the body, which is based on the drug's half-life, usually within 12 to 24 hours. With all anticoagulants there is a risk of bleeding. Therefore, in addition to the risk of VTE, physical therapists should be aware of and assess for risk of bleeding in all patients. Factors associated with high risk of bleeding are: active bleeding; acute stroke; acquired bleeding disorders (eg, acute liver failure); concurrent use of anticoagulants known to increase the risk of bleeding (eg, Coumadin with an international normalized ratio >2); lumbar puncture, epidural, or spinal anesthesia expected to be given within next 12 hours; thrombocytopenia (platelet count less than 7,500); uncontrolled systolic hypertension (defined as blood pressure of 230/120 mm Hg or higher), and untreated inherited bleeding disorders, such as hemophilia or von Willebrand disease.²⁰

Action statement profile

Aggregate Evidence Quality: Level I

Benefit: Decreased risk of subsequent LE DVT or PE; decreased risk of adverse effects of bed rest

Risk, Harm, Cost: Risks associated with use of anticoagulants include increased risk of bleeding. If an anticoagulant is not at a therapeutic level, there may be an increased risk of PE with mobilization.

Benefit-Harm Assessment: Preponderance of benefit

Value Judgments: The evidence for mobility to prevent VTE is strong, although the evidence on when to initiate mobility may not be as strong and is based on the patient achieving the therapeutic level of the anticoagulant. Physical therapists should mobilize patients as soon as possible after diagnosis of VTE as long as the risk of PE is decreased. Achieving the therapeutic level of the anticoagulant has been shown to diminish the risk of developing a PE.

Intentional Vagueness: Specific anticoagulants or their therapeutic levels are not recommended. Instead, evidence-based guidelines and algorithms have been provided for guidance. Physical therapists should work within their health care system to develop institution-specific protocols.

Role of Patient Preference: Patients should be aware of the anticoagulation they are prescribed and the effect that the anticoagulant will have on their lifestyle (eg, amount of medical monitoring, risk of bleeding, foods to avoid, risk of brain bleed). In addition, patients should be informed regarding the risk of immobility in developing further VTE and the benefit of mobility.

Exclusions: The risk of bleeding is present when anyone takes anticoagulants. However, patients with HIT, a history of HIT, recent bleeding events, or increased risk of bleeding should be prescribed treatment other than anticoagulation, including mechanical compression or intravenous filters.

Summary of evidence

Patients who have a documented LE DVT and have reached therapeutic levels of the prescribed anticoagulant should be mobilized out of bed and ambulate to prevent venous stasis. In doing so, deconditioning is minimized, length of hospital stay may be shortened, and other adverse effects of prolonged bed rest (eg, decubiti) can be avoided. A common concern for mobilizing a patient with an LE DVT is that the clot will dislodge and embolize to the lungs, causing a potentially fatal PE. However, early ambulation has been shown to lead to no greater risk of PE than bed rest for people with a diagnosed LE DVT who have been treated with anticoagulants.²⁸

A meta-analysis showed the absence of a higher risk of new PE or other adverse clinical events when individuals were ambulated instead of kept on bed rest.²⁸ The studies included in this meta-analysis had differences in the timing of ambulation following initiation of anticoagulation. Nevertheless, the conclusion arrived at was that “early” ambulation was possible as soon as the level of effective anticoagulation had been reached.²⁸ In 2 earlier systematic reviews, 1 with 3 studies totaling 300 patients⁹¹ and 1 with 9 studies,²³ similar conclusions were reported. A potentially reduced risk for extension of a proximal LE DVT and reduced long-term symptoms of PTS with early mobility was reported, demonstrating the benefits of early mobilization of patients having LE DVT.²⁹

In 2012, the ACCP published guidelines on antithrombotic therapy and prevention of thrombosis provided a moderate strength recommendation that patients with an acute LE DVT should receive early ambulation over initial bed rest because of the potential to decrease PTS and improve quality of life.²⁷

In summary, early mobilization of patients with an LE DVT who are anticoagulated does not put the patient at increased risk of PE. Early mobilization has added benefits. The GDG recommends mobilizing patients with an LE DVT once anticoagulation is initiated and therapeutic levels have been achieved. Based on the evidence that exists on time to peak therapeutic levels of the anticoagulants (refer to eTable), expert consensus exists to recommend early ambulation of individuals with an LE DVT who are receiving anticoagulation and have reached their peak therapeutic levels based on the specific anticoagulation medication they are prescribed.

Action statement profile

Aggregate Evidence Quality: Level II

Benefit: Secondary prevention of recurrent DVT/PE or PTS and faster resolution of LE DVT signs and symptoms

Risk, Harm, Cost: Improper fit can lead to skin irritation, ulceration, or interruption of blood flow

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: None

Intentional Vagueness: Types of mechanical compression were not recommended. Physical therapists should work within their health care system to develop institution-specific protocols.

Role of Patient Preference: Ease of use, comfort level, and ability to operate mechanical compression equipment properly should be discussed with patients and their families or caregivers.

Exclusions: Patients who have severe peripheral neuropathy, arterial insufficiency, dermatologic diseases, or lesions may have contraindications to selective mechanical compression modes.

Summary of evidence

In the ninth edition (2012) CPG by the ACCP, recommendations pertaining to mechanical compression based on moderate-quality data for patients with diagnosed LE DVT were given.⁹¹ For patients with acute symptomatic LE DVT and in those having PTS, GCS were suggested based on studies using at least 30 mm Hg of pressure at the ankle. In patients with severe PTS of the leg not adequately relieved with GCS, a trial with IPC was suggested.

Systematic reviews pertaining to the adjuvant use of mechanical compression garments for patients who are anticoagulated and have acute VTE (eg, LE DVT) while on bed rest or with early ambulation compared with controls provide supportive evidence for their use.⁹² The 7 RCTs in these reviews concluded that mechanical compression lowered the relative risk for progression of a thrombus or the development of a new thrombus.

Two earlier RCTs conducted over 2 years on patients who had symptomatic, first-occurrence proximal LE DVTs concluded that knee-length elastic GCS with interface pressures of 30 to 40 mm Hg at the ankle reduced the incidence of mild, moderate, and severe PTS compared with controls who did not wear GCS.^93,94 In stark contrast, a more recent randomized placebo-controlled multicenter trial with 410 patients having a first proximal LE DVT followed for 2 years (ie, SOX trial) did not support the routine wearing of GCS (ie, knee length at 30–40 mm Hg compared with ≤5 mm Hg placebo knee-length stockings) after LE DVT.⁹⁵

Two additional RCTs^96,97 on patients who were anticoagulated and had acute LE DVT combined early ambulation with the wearing of either inelastic (rigid) stockings above the knee (ie, zinc plaster Unna boots providing 50 mm Hg of interface pressure at the ankle) or thigh-length elastic stockings (ie, providing an interface pressure of 30 mm Hg at the ankle) compared with control patients on bed rest. The combination of GCS with ambulation resulted in a faster resolution of pain and swelling and an increased quality-of-life outcome measure.

In summary, the evidence to support mechanical compression methods as effective treatment interventions for secondary VTE prevention varies according to patient VTE risk profile, acute (eg, hemodynamic stability) versus chronic (eg, PTS concern) status, degree of signs (eg, swelling) and symptoms (eg, pain), and consideration for potentially harmful outcomes (eg, skin lesions). Whether used adjunctively along with anticoagulants, alone as in patients when anticoagulant use is contraindicated, or in combination (eg, ambulation plus GCS) with or without anticoagulation, mechanical compression use has mostly been favorable. Controversy persists, however, regarding whether to support the routine use of mechanical compression (eg, GCS) for LE DVT management and secondary prevention. Studies tend to suggest that having GCS compression forces at the ankle, regardless of whether elastic or rigid, is beneficial when ≥30 mm Hg, especially when combined with early ambulation. Regardless of whether the mode of mechanical compression is by GCS or another means (eg, IPC), the optimal mechanical compression treatment strategy has yet to be identified.⁹⁸

Action statement profile

Aggregate Evidence Quality: Level V

Benefits: Decreased risk of PE reduced in-hospital fatality rate in patients who are stable and those who are unstable

Risk, Harm, Cost: IVC complications and potential overuse of IVC filters may increase costs

Benefit-Harm Assessment: Preponderance of benefit over harm for patients who have an acute proximal LE DVT and contraindications to anticoagulants

Value Judgments: An IVC filter is valuable for patients at high risk who are unable to be given anticoagulants.

Intentional Vagueness: None

Role of Patient Preference: None

Exclusions: Patients with contraindications to IVC filter placement

Summary of evidence

Inferior vena cava filter placement is a type of percutaneous endovascular intervention for venous thromboembolic disease and is usually performed by an interventional radiologist. Venous access is via the right internal jugular or right femoral veins. The best placement location for the IVC filter to prevent lower extremity and pelvic VTE is just inferior to the renal veins.⁹⁹ Table 7 lists the indications and contraindications for IVC filter placement. In general, IVC filters are used to prevent PE in patients who are thought to be at high risk for LE DVT or PE, have contraindications to anticoagulants, or for whom medications have not been effective. Findings are mixed regarding the effectiveness of IVC filters in preventing PE, and there are risks associated with IVC filter placement (Tab. 8). Following placement of an IVC filter, the patient should be mobilized once he or she is hemodynamically stable and there is no bleeding at the puncture site.⁹⁹ Physical therapists should monitor ambulation and mobility to ensure patient safety and to determine the appropriate level of required assistance prior to the patient being discharged.⁹⁹

Action statement profile

Aggregate Evidence Quality: Level V

Benefits: Mobility has demonstrated a decreased risk of VTE

Risk, Harm, Cost: Potential increased risk of PE should the LE DVT embolize

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: As movement specialists, physical therapists recommend mobilization over bed rest due to the documented benefits of early mobilization.

Intentional Vagueness: Specific guidelines are not provided because it is rare that a patient will not have anticoagulants prescribed or an IVC filter in this country. Each patient should be considered individually.

Role of Patient Preferences: Patients should be informed of the risks and benefits of bed rest and inactivity and of mobilization.

Exclusions: Any LE DVT present above the knee

Summary of evidence

There may be times when a patient has a diagnosed LE DVT but no medical interventions are initiated. The patients may have contraindications for receiving anticoagulant medications or they do not meet the criteria for an IVC (eg, in palliative care or hospice care). In these situations, a consult with the primary physician or medical team should guide the decision to mobilize the patient. Continuing to remain on bed rest will only increase the risk of additional VTE and other adverse effects of immobilization. At some point, the patient needs to return to daily activities, and it might be appropriate to begin mobilization even though an untreated LE DVT is present. In other situations, the reason for not addressing the LE DVT may be short term. It may be wise to wait until anticoagulation can begin. The physical therapist needs to discuss all of these factors with the interprofessional team and the patient when making a clinical judgment about mobilization. Although a physician may order physical therapy to increase the physical activity level of a patient, it is the physical therapist's clinical decision whether to mobilize the patient based on the available information about the patient's LE DVT and risk status.

Action statement profile

Aggregate Evidence Quality: Level III

Benefits: Decreased risk of hemorrhage due to falls

Risk, Harm, Cost: Immobility versus risk of falling

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: Fall prevention is a prudent step in managing patients who are at increased risk for bleeding.

Role of Patient Preference: None

Exclusions: None

Summary of evidence

A major bleed event is a possible complication in patients taking an anticoagulant medication. Use of oral anticoagulants increases the risk of intracerebral bleeds by 7 to 10 times.¹⁰⁰ Individuals who fall while on long-term anticoagulation have higher rates of mortality than those not on these medications due to a subsequent major bleed.^101,102 However, the benefits of being on an anticoagulant outweigh the risk of a major bleed.^103,104 Therefore, patients at high risk for falls are not automatically excluded from receiving anticoagulants and will receive these medications when it is considered medically beneficial.

Age is considered a major risk factor for falls. People 75 years of age and older have the highest rate of falls, and 1 in 3 individuals over the age of 65 years fall each year.^105,106 Because of the risk of falls associated with age, the National Institute for Health and Care Excellence, the American Geriatrics Society, and the US Preventive Services Task Force all recommend screening for fall risk in all older adults.^107–109 Individuals should be asked about feelings of unsteadiness and falls over the last year. If a fall or unsteadiness has been reported, further assessment of strength, balance, and other risk factors should be completed. In general, the population of individuals on anticoagulants is made up of older adults who would benefit from fall risk screening.^4,110 The Centers for Disease Control and Prevention's Stopping Elderly Accidents, Deaths and Injuries (STEADI) toolkit provides physical therapists and interprofessional team members with an evidence-based tool to improve fall prevention in clinical practice.

Action statement profile

Aggregate Evidence Quality: Level I

Benefit: Faster resolution of LE DVT signs and symptoms and decreasing PTS severity

Risk, Harm, Cost: Improper fit can lead to skin irritation, ulceration, and interruption of blood flow.

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: None

Intentional Vagueness: The specific types of mechanical compression were not recommended. Physical therapists should work within their health care system to develop institution-specific protocols.

Role of Patient Preference: Ease of use, comfort level, and ability to operate mechanical compression equipment properly should be discussed with the patient and caregiver.

Exclusions: Patients who have severe peripheral neuropathy, arterial insufficiency, dermatologic diseases, or lesions may have contraindications to selective mechanical compression modes.

Summary of evidence

Approximately 1 in 3 patients with LE DVT will experience PTS within 5 years, and in 5% to 10% of these patients, PTS occurs in its most severe form as venous ulceration.^13,111,112 The potential exists that should infection develop, septicemia or septic shock could result.¹¹³ Patients with PTS experience chronic complaints of leg pain secondary to the DVT, which may include the sense of the leg feeling heavy, cramping, and itching, and, in severe cases, venous ulceration.^13,98,114 The pathogenesis of PTS is thought to be related to venous hypertension. As the thrombus initiates an inflammatory response, venous valves may become damaged during this process of thrombus resolution, which is often incomplete over time. The damaged venous valves cause valvular reflux, and as remodeling of the vein wall occurs, they may become stiff and contribute to increased outflow resistance, which increases blood pressure in the veins. This increase in transluminal pressure causes leakage into the interstitial space, leading to edema and skin changes. Microcirculation and blood supply to the leg muscles become compromised, which can lead to venous ulcerations in the more severe instances of PTS.⁹⁸ With clinical findings of PTS being similar to that of an acute LE DVT, concern is raised regarding the negative impact that PTS may have on a person's quality-of-life experience.^{13,111,113,115–117} For reasons described above, physical therapists should consider screening all patients with a history of LE DVT, past and current, for signs and symptoms of PTS. Once PTS is suspected, a specific and sensitive rating instrument referred to as the Villalta scale can be used to grade the severity of PTS.^117–120

A meta-analysis conducted on 5 RCTs determined that venous compression stockings or compression bandages are effective in reducing PTS in patients.¹¹⁹ In patients with LE DVT receiving GCS compared with controls, mild-to-moderate PTS occurred in 64 (22%) of 296 patients treated with venous compression compared with 106 (37%) of 284 controls. Severe PTS occurred in 14 (5%) of 296 patients treated compared with 33 (12%) of 284 controls. Development of any degree of PTS occurred in 89 (26%) of 338 patients treated compared with 150 (46%) of 324 controls. Thus, GCS reduces the severity of PTS, although there was a wide variation in the type of stockings used, time interval from diagnosis to application of stockings, and duration of treatment.

Two Cochrane reviews, separated by 1 year, were conducted to determine the treatment interventions of IPC or GCS according to PTS severity. Findings from the first review based on 2 RCTs¹¹² included favorable trends using higher pressures of IPC over that of lower pressures and that there was not enough evidence to support the use of elastic GCS (30–40 mm Hg pressures at the ankle versus placebo stockings) in patients with mild-to-moderate PTS severity. The second review, based on 3 RCTs,¹²⁰ provided statistically significant evidence that elastic GCS of 20 to 40 mm Hg interface pressure at the ankle reduce the severity of PTS after LE DVT.

A separate RCT involving 169 patients with a first or recurrent proximal LE DVT after receiving 6 months of standard treatment to wear GCS or not was conducted.¹²¹ The incidence of PTS was 11 patients (13.1%) in the treatment group compared with 17 individuals (20.0%) in the control group. No venous ulceration was observed in either group, with symptom relief significantly in favor of compression treatment during the first year but not thereafter. The conclusion reached was that prolonged use of GCS after proximal DVT significantly reduces symptoms and signs of postthrombotic skin changes.

In the evidence-based guideline by the Finnish Medical Society Duodecim, immediate bandaging for compression during the acute phase of DVT (up to the groin, if needed) is recommended in circular rather than figure-eight turns.³¹ In addition, the patient should be mobilized as soon as clinically possible, and GCS (class II compression) should be worn for at least 2 years.

Pooled results from 4 RCTs in another systematic review¹²² in patients with confirmed proximal LE DVT used compression bandaging (inelastic or elastic), with or without early ambulation, as an intervention for PTS.¹²² Results stressed the importance of activating the calf muscle pump in addition to compression bandaging, a message echoed by other authors more recently.¹²³

The lack of uniformity in reporting standards, such as the timing, duration, and degree of compression interface pressure, among other descriptors, makes it difficult for meaningful comparisons among studies. This concern has been raised by more than one investigative group.^98,122–125

In summary, mechanical compression (eg, with IPC or compression bandaging, activation of the calf muscle pump), with or without ambulation, is the cornerstone in the treatment of PTS. The intervention strategy is primarily focused on decreasing venous pressure in the involved lower extremity, enhancement of the microcirculation, and reduction of the edema. The efficacy in treating PTS after confirmed acute LE DVT and its development during the subacute period or as a debilitating chronic condition thereafter do favor the early application and prolonged use of mechanical compression. The lack in uniformity of the methods and prescriptive protocols followed in the use of mechanical compression lends itself to controversy. Nevertheless, the preponderance of quality evidence does warrant a strong recommendation.

Action statement profile

Aggregate evidence quality: Level V

Benefit: Decreasing the incidence of LE DVT recurrence and minimizing the severity of PTS signs and symptoms in order to enhance functional mobility and a person's quality of life experience

Risk, Harm, Cost: Improper fit of mechanical compression can lead to skin irritation, ulceration, and interruption of blood flow.

Benefit-Harm Assessment: Preponderance of benefit over harm

Value Judgments: None

Intentional Vagueness: No specific types of mechanical compression were recommended. Physical therapists should work within their health care system to develop institution-specific protocols.

Role of Patient Preference: Ease of use, comfort level, and ability to operate mechanical compression equipment properly

Exclusions: Patients who have severe peripheral neuropathy, arterial insufficiency, decompensated heart failure, dermatologic diseases, or lesions may have contraindications to selective mechanical compression modes.

Summary of evidence

Whether or not a VTE (ie, LE DVT, PE, or PTS) has a clear cause (eg, surgery, trauma, forced immobilization) or is unprovoked (ie, in the absence of a known risk factor), physical therapists should remain vigilant in screening patients for signs and symptoms of recurrent VTE.¹²⁶ It is estimated that the risk of recurrence can reach 5% to 10% during the first 6 to 12 months¹²⁷ and 10% to 30% within 5 years¹²⁸ following a documented first-episode VTE. According to one recent CPG, the rate of VTE recurrence for patients not on long-term anticoagulation is 5% per year.³⁶ When pharmacologic anticoagulation is provided, the recurrence rate for VTE within the first 6 months was reported to be less than 2.5% in one RCT¹²⁹ and between 1.3% and 7.1% over a period of 18 to 24 months in another RCT.¹³⁰ Nevertheless, the incidence of fatal and nonfatal VTE recurrence in patients who are anticoagulated following confirmed VTE in the short term of 3 months was reported to be 0.4% and 3%, respectively, in one meta-analysis,¹³¹ and a fatality incidence due to PE of 1.68% was found in a large cohort study.¹³² These findings serve to underscore the importance of having physical therapists monitor patients for VTE recurrence regardless of whether over the short term or the long term.

The ability of a clinician to accurately predict level of risk for recurrent VTE (eg, low versus high) has been investigated using the Pulmonary Embolism Severity Index (PESI) clinical prediction rule and found to be of merit.^129,133 Additionally, the use of global clinical judgment that takes into account all of a patient's signs and symptoms (ie, unstructured clinician gestalt) may be superior to clinical prediction rule use.¹³⁰

The ability to distinguish or recognize that PTS is present is important for the clinician to determine. Postthrombotic syndrome is defined as a combination of clinical signs and symptoms occurring after an LE DVT. One study examined 6 different scoring systems that are intended to document the presence and severity of PTS based on variable clinical signs (ie, 11) and symptoms (ie, 12) used between them.¹¹⁴ Because PTS also involves a patient's subjective report of symptoms, using the objective PTS indicator of skin pigmentation changes that highly correlate with findings from duplex sonography for venous reflux occlusion was advocated.

Thrombosis resolution is often incomplete, with as many as 50% of legs affected by DVT still having residual vein thrombosis years after the LE DVT is first diagnosed.⁹⁸ The negative impact on generic life-of-quality measures (eg, 36-Item Short-Form Health Survey [SF-36] sections for physical functioning and bodily pain) has life-quality consequence comparable to chronic medical conditions such as diabetes and heart failure.¹¹⁷ It is prudent, therefore, that physical therapists recognize signs and symptoms of PTS and intervene with education, hydration, early mobilization, mechanical compression, and referral for medication when appropriate (refer to key Action Statement 3). For example, mechanical compression aims to manage factors responsible for the pathogenesis of VTE (ie, Virchow's triad of hypercoagulopathy, venous stasis, and endothelial damage) by reducing swelling, accelerating venous return, and improving muscle pump function.¹²²

In summary, patients who have a prior history of VTE are at high risk for recurrent VTE, especially when they are immobilized or are of advanced age. It is judicious to screen for VTE recurrence using a clinical prediction rule (eg, PESI, Padua score, Wells criteria for LE DVT; Geneva Risk Score) for objective documentation purposes, although global clinical judgment that would favor intervention for secondary VTE prevention should not be overlooked. Once VTE is diagnosed, clinical practice has shifted away from immobilization with bed rest and toward early ambulation with or without adjunctive mechanical compression. From the literature examined, the degree to which recurrent VTE is treated as a secondary prevention should be a priority. Thus, clinical judgment and expert opinion remain for deciding the clinical actions to take.