EBM Series: Outpatient Management of DVT and PE

Objectives

  1. To understand the prevalence and morbidity associated with deep venous thrombosis (DVT) and pulmonary embolism (PE)

  2. To develop a framework for selecting individuals most appropriate for outpatient management of VTE

  3. To describe outpatient options for VTE

 

Definitions

Pulmonary embolism (PE): blood clot formation within a branch of the pulmonary arterial system

Deep venous thrombosis (DVT): blood clot formation in a deep vein, most commonly within the lower leg, thigh, or pelvis

Venous thromboembolism (VTE): a collective term referring to both DVT and PE

 

Epidemiology

  • Approximately 900,000 diagnoses of DVT or PE in the US per year (1)

  • Estimated incidence of 1 per 1000 adults, although limited by underdiagnosis (2)

  • About two-thirds manifest as DVT, and one-third as PE (2)

  • 30-day mortality in Medicare beneficiaries is 5.1 and 9.1 percent for DVT and PE respectively (3)

  • PE is responsible for about 100,000 deaths per year (1) 

Who is sent home?

A 2016 study by Singer et al. found that 90% of PE and 52% of DVT patients presenting through the emergency department were hospitalized for initiation of anticoagulation and monitoring. Fifty-one percent of patient with PE in that study were considered low-risk based on sPESI score, many of whom would have been appropriate for discharge with outpatient initiation of anticoagulation (4). Several clinical decision tools exist to help clinicians risk-stratify patients, as discussed below. When utilized appropriately, these tools can be used to reduce hospitalization of otherwise low-risk patients with VTE (4-6).

 

5 steps to manage DVT and PE as outpatient

Adapted from: A clinical decision framework to guide the outpatient treatment of emergency department patients diagnosed with acute pulmonary embolism or deep vein thrombosis: Results from a multidisciplinary consensus panel (6):

  1. Make the diagnosis of DVT or PE

  2. Stratify your patient’s risk of clinical decompensation

  3. Stratify your patient’s risk of bleeding on anticoagulation

  4. Select and start an appropriate anticoagulant

  5. Ensure your patient has access to medications with timely follow-up and discussion of appropriate return precautions

 

General inclusion and exclusion criteria

Inclusion criteria:

  • Age 18 to 80

  • BMI < 40*

  • Able to follow-up with PCP within 7 days

  • Able to comply with home medication regimen

  • Adequate home support

Exclusion criteria:

  • Known coagulopathy or currently on anticoagulation

  • New or active* malignancy

  • Renal dysfunction (CrCl < 30)

  • Currently on dual antiplatelet therapy

  • Active use of strong CYP450 3A4 agents

*relative contraindication

 

Step 1: Diagnosis of DVT or PE

Diagnosis of DVT

  • Venous duplex ultrasound

 

Diagnosis of PE

  • CT pulmonary angiography (CT-PA or CTPE)

  • VQ scan

  • Although not necessary, point-of-care or comprehensive echocardiography can be useful to identify other high-risk features discussed below

     

Step 2: Stratify your patient’s risk of clinical decompensation

Hemodynamic instability

  • SBP < 100

  • HR > 100 to 110

  • Tachypnea or hypoxia

  • During prehospital or ED course

  • INCLUDES pre-syncope and syncope (indicative of transient period of hypotension)

 

Clinical decision rules

  • Apply simplified PESI or Hestia clinical decision rule

  • Hestia clinical decision rule is more specific for identifying patients appropriate for outpatient management, and includes not only physiologic considerations, but social considerations as well (7)

  • When compared to simplified PESI, Hestia criteria has similar rates of home treatment and adverse effects, but requires less frequent over-ruling by clinician judgment (7)

 

High-risk imaging findings

  • Radiographic evidence of right heart strain on CT-PA or bedside echocardiogram

  • Thrombus located in the main pulmonary artery branches or “saddle” physiology

  • Clot in transit (visualized within the right heart) on CT or echocardiogram

 

High-risk lab findings

  • Troponin level elevation

  • BNP elevation

 

Associated high-risk DVT

  • Includes iliofemoral clots, extensive clot burden, and clots with associated skin changes (further discussed below)

 

High-risk EKG findings

  • New right heart strain pattern

  • New RBBB

  • Deep T-wave inversions

  • S1Q3T3 pattern

  • New-onset arrythmia (e.g. atrial fibrillation or atrial flutter)

 

Risk stratification of DVT

In the absence of associated PE, risk stratification of DVT is relatively simple, and involves assessing for only a few high-risk features.

 

Iliofemoral DVT or extensive clot burden

  • Associated with greater morbidity and mortality (8)

  • Includes those patients appropriate for mechanical thrombolysis

 

Phlegmasia cerulea dolens or phlegmasia alba dolens

  • Reddish or milky-white discoloration of the affected extremity indicative of severe venous outflow obstruction and congestion

  • Often associated with severe pain and extensive clot burden 

Step 3: Stratify your patient’s risk of bleeding on anticoagulation

Stratifying bleeding involves consideration of multiple risk factors listed below. Although frequently used, scores such as VTE-BLEED or HAS-BLED have limited utility in the emergency department, as they are designed to quantify the risk of continued long-term anticoagulation, and not to direct the initiation of anticoagulation in acute VTE.

 

Risk factors:

  • Active bleeding or recent (< 1 month) major bleeding*

  • Thrombocytopenia (< 100×10^3 / µL)

  • Recent major surgery, trauma, or stroke

  • Recent epidural, neurosurgical, or cerebrospinal procedure

  • Active malignancy of critical site intolerant of bleeding

    • Intracranial, spinal, ocular, oropharyngeal, or retroperitoneal

  • Cirrhosis or severe liver dysfunction

  • Severe renal dysfunction (CrCl < 30) or ESRD on dialysis

*clinician judgment

 

Step 4: Select and start an appropriate anticoagulant

DOACs are the preferred agent for most patients seen in the emergency department. Pregnant patients should be started on low-molecular-weight heparin after discussion with OB/GYN or maternal-fetal medicine. Patients requiring anticoagulation with warfarin due to co-morbid conditions are not appropriate for discharge from the emergency department, as they are considered high-risk due to their co-morbidities. These patients should be started on heparin and admitted for observation and bridge to warfarin.

 

DOACs (e.g. apixaban and rivaroxaban)

  • Preferred agent for most patients

  • Ask about timing of other medications and ease of taking medications

    • Apixaban is twice daily dosing, but has lowest rate of adverse bleeding

    • Rivaroxaban is once daily dosing, but has higher rates of bleeding, especially GI bleeds (9)

 

Low molecular weight heparin (e.g. lovenox)

  • Preferred in pregnancy (10)

  • Consult OB or MFM prior to discharging a patient with VTE

 

Warfarin (coumadin)

  • Preferred in patients with severe liver dysfunction, prosthetic valves, antiphospholipid syndrome, or high-risk of bleeding requiring reversal (7, 11)

  • These patients should be admitted for initiation of anticoagulation with heparin bridge therapy

 

Step 5: Ensure your patient has access to medications with timely follow-up and discussion of appropriate return precautions

  • Give the first dose of anticoagulant in the emergency department, and instruct patients to return to the emergency department if they are unable to fill their prescription

  • Ensure patients have short-term follow-up with primary care, ideally within 7 to 10 days

  • Discuss signs of adverse bleeding and worsening thromboembolic disease requiring prompt return to the emergency department


AUTHORED BY : BEJAN KANGA, MD

FACULTY EDITING BY: NIK SEKOULOPOULOS, MD


References

  1. Data and Statistics on Venous Thromboembolism. Centers for Disease Control and Prevention. Updated May 15, 2024. Retrieved from: https://www.cdc.gov/blood-clots/data-research/facts-stats/index.html.

  2. Cushman M. Epidemiology and risk factors for venous thrombosis. Semin Hematol. 2007 Apr; 44(2):62-9.

  3. Lutsey PL, Zakai NA. Epidemiology and prevention of venous thromboembolism. Nat Rev Cardiol. 2023 Apr; 20(4):248-262.

  4. Singer AJ, Thode HC Jr, Peacock WF 4th. Admission rates for emergency department patients with venous thromboembolism and estimation of the proportion of low risk pulmonary embolism patients: a US perspective. Clin Exp Emerg Med. 2016 Sep; 3(3):126-131.

  5. Bledsoe JR, Woller SC, Stevens SM, et al. Management of Low-Risk Pulmonary Embolism Patients Without Hospitalization: The Low-Risk Pulmonary Embolism Prospective Management Study. Chest. 2018 Aug; 154(2):249-256.

  6. Kabrhel C, Vinson DR, Mitchell AM, et al. A clinical decision framework to guide the outpatient treatment of emergency department patients diagnosed with acute pulmonary embolism or deep vein thrombosis: Results from a multidisciplinary consensus panel. J Am Coll Emerg Physicians Open. 2021 Dec; 2(6):e12588.

  7. Roy PM, Penaloza A, Hugli O, et al. Triaging acute pulmonary embolism for home treatment by Hestia or simplified PESI criteria: the HOME-PE randomized trial. Eur Heart J. 2021 Aug; 42(33):3146-3157.

  8. Jiménez D, Aujesky D, Díaz G, et al. Prognostic significance of deep vein thrombosis in patients presenting with acute symptomatic pulmonary embolism. Am J Respir Crit Care Med. 2010 May; 181(9):983-91.

  9. Adeboyeje G, Sylwestrzak G, Barron JJ, ET AL. Major Bleeding Risk During Anticoagulation with Warfarin, Dabigatran, Apixaban, or Rivaroxaban in Patients with Nonvalvular Atrial Fibrillation. J Manag Care Spec Pharm. 2017 Sep; 23(9):968-978.

  10. Bates SM, Rajasekhar A, Middeldorp S, et al. American Society of Hematology 2018 guidelines for management of venous thromboembolism: venous thromboembolism in the context of pregnancy. Blood Adv. 2018 Nov 27; 2(22):3317-3359.

  11. Pengo V, Denas G, Zoppellaro G, et al. Rivaroxaban vs warfarin in high-risk patients with antiphospholipid syndrome. Blood. 2018 Sep; 132(13):1365-1371.