#192: Live! The Clot Thickens: DVT and DOACs in Children

September 23, 2026 | By Sam Masur

Audio

Don’t let a clot catch you off guard! Recorded live at the University of Alabama at Birmingham’s Pediatric Grand Rounds, we’re joined by Dr. Hope Wilson (UAB) to untangle deep vein thrombosis. Dr. Wilson teaches us which veins actually count as “deep,” prescribing DOACs to kids, and how anticoagulation duration has changed. Plus a rapid fire round on upper extremity clots, Lemierre’s, and what to do when anticoagulation is off the table. Your enthusiasm for VTE is about to propagate.

DVT and DOAC Pearls

1. Don’t memorize the deep veins — memorize the superficial ones. Great and small saphenous in the leg, basilic and cephalic in the arm. Everything else is deep, including the deceptively named superficial femoral vein.
2. Anticoagulate deep venous thromboses, not superficial ones. The exception: a superficial thrombus within 5cm of the deep vein junction, where 6 weeks of anticoagulation can be offered to prevent propagation.
3. Per Kids-DOTT, a first-time provoked clot without malignancy or PE can be treated for as little as 6 weeks, with re-imaging at 6 weeks to confirm the thrombus is no longer occlusive. 
4. All three FDA-approved pediatric DOACs were studied with a 5-day parenteral lead-in, which is why the labeling calls for it — a quirk of trial design rather than a biologic requirement.
5. Warfarin is still the gold standard in antiphospholipid antibody syndrome. Skip DOACs for APS, gut malabsorption, or a significant drug-drug interaction.
6. Counseling matters as much as the prescription. When on anticoagulation, no aspirin or NSAIDs (unless it’s aspirin for a complex cardiac condition), no contact sports, and expect heavier menses in teenage females.

DVT and DOAC Notes 

Deep Vein Thrombosis

Presentation

The classical presentation of deep vein thrombosis (DVT) in children is unilateral erythema/bruising/discoloration, pain, and edema in an extremity.

When it comes to distinguishing deep from superficial veins, Dr. Wilson recommends simply remembering the superficial veins—everything else is considered deep.

• Superficial Veins of the Leg: Great Saphenous and Small Saphenous Veins
  • Don’t get confused, the superficial femoral vein is a deep vein!
• Superficial Veins of the Arm: Basilic Vein and Cephalic Veins

Workup

Venous duplex ultrasound is the standard of care for DVT diagnosis.

Treatment

The initial goals of anticoagulation are not to remove the clot. The body will dissolve the clot itself. The goal of anticoagulation is to stabilize the clot and prevent propagation and/or embolization.

Indications

For the majority of cases, Dr. Wilson recommends anticoagulation for all deep vein thromboses, but not superficial thromboses. 

Contraindications to anticoagulation are active bleeding, recent recovery from GI or intracranial bleed, or plan for surgery. Thrombocytopenia is only a contraindication if the patient is bleeding as well.

Determine if Provoked or Unprovoked

Identify any risk factors that led to the clot. Common risk factors include hypercoagulable states, malignancy, central lines, combined oral contraceptives, long flights, and surgery. For estrogen containing medications, it’s more common to clot during the early introduction of the medication (most common within 2 months and risk decreases substantially after 12 months)

Expert opinion: for any thrombus without an obvious explanation, Dr. Wilson will send initial antiphospholipid antibody syndrome testing (lupus anticoagulant, anti-cardiolipin, and b2 glycoprotein antibodies). Although not diagnostic without subsequent testing, this may guide her initial treatment regimen pending confirmatory testing. 

Duration

For a clot due to a transient risk factor (provoked), children can be treated for as little as 6 weeks according to the Kids-DOTT trial (Goldenberg et al, 2022). The recommendation is to re-image occlusive thrombi after 6 weeks of anticoagulation. If no longer occlusive (can still be present), anticoagulation can be stopped. Most importantly, the Kids-DOTT trial only studied children with a first-time provoked clot without malignancy or pulmonary emboli. 

For all children with persistent occlusive thrombi, recurrent thromboembolism, pulmonary embolism, or malignancy, the recommendation is to treat for a minimum of 3 months. If clot is unprovoked, the recommendation is a minimum of 6 months. Of note, there is no standard of care on how to manage cancer associated thrombosis in children.

Expert Opinion: Dr. Wilson recommends reimaging at the end of treatment, regardless of duration.

Anticipatory Guidance

Dr. Wilson advises children on anticoagulation against the use of aspirin and other NSAIDs, except for those taking aspirin for complex cardiac conditions. She also advises against contact sports. For teenage females, they will likely have heavier bleeding during menses.

For the active toddler, there is little providers can do to prevent them from running, tripping, and falling. However, she recommends parents bring their child in for a medical evaluation after any trauma.

Medications

Direct Oral Anticoagulants (DOAC)

As of 2026, there are 3 FDA-approved direct oral anticoagulants. Dabigatran is a direct thrombin inhibitor. Apixaban and Rivaroxaban are direct factor Xa inhibitors. 

Due to trial design for pediatric FDA approval, all DOACs were studied with a 5 day parenteral lead in. Therefore, FDA recommendation is for 5 days of enoxaparin (or unfractionated heparin) prior to transitioning to the oral form, however Dr. Wilson will consider starting a DOAC earlier depending on logistics and medication availability. Please note, if the child will be treated with adult dosing due to age/size, he/she can use the adult initiation “starter pack” rather than a parenteral lead in.

Dr. Wilson recommends against DOACs when there is concern for either gut malabsorption, antiphospholipid antibody syndrome, or a drug-drug interaction. Currently, DOACs are not recommended in children with renal and hepatic impairment. However, this is due to exclusion criteria in the studies used for FDA approval rather than a true contraindication. This will likely change over time.

As of 2026, the Xa reversal agents were taken off the market due to increased risk of thrombosis. Therefore, Dr. Wilson recommends transfusion of prothrombin complex concentrate (PCC) to provide external clotting factors for any child in need of a reversal agent. 

Rivaroxaban

Approved from birth onwards (at least 37 weeks gestational age) with a minimum weight of 2.6kg. Dosing varies with size. Infants are dosed three times daily, young children are dosed twice daily, and if ≥30kg, dosing becomes once daily. 

Apixaban

Approved from birth onwards (at least 34 weeks gestational age) with a minimum weight of 2.6kg. Dosed twice daily. Data suggests that apixaban has a lower risk of bleeding than rivaroxaban, so Dr. Wilson may recommend it for patients at risk for GI bleed or heavy menstrual bleeding. However, the pediatric data is limited (Gao et al, 2024) and this is mostly corroboration from adult data (Castellucci et all, 2026).

Dabigatran

Approved for children ages ≥ 3 months. Dosing age and weight based.

Low Molecular Weight Heparin

Often chosen as a bridging agent or when DOAC is contraindicated. Typically dosed at 1mg/kg twice daily and then adjusted based on anti-Xa level. Anti-Xa goal is 0.5-1.0 and should be strictly measured 4-6 hours after a dose, ideally the third or fourth. Enoxaparin is cleared via the kidney, so dosing will likely need to be lowered in chronic kidney disease.

Warfarin

Warfarin remains the gold standard for patients with antiphospholipid antibody syndrome (APS). Much of the evidence supporting warfarin over DOACs in APS comes from patients with triple-positive disease (lupus anticoagulant, anticardiolipin antibodies, and anti-β2-glycoprotein antibodies) (Pengo et al, 2018).

Prophylaxis

Indications

Secondary prophylaxis is prophylaxis for patients who have already had their first clot. This is recommended in patients with a new provoking exposure. The most common cause in pediatrics is a central line. Dr. Wilson recommends anticoagulation for those with a central line and secondary risk factor (inflammation, ongoing malignancy, etc) through the duration of the line.

Note: The decision to transition from treatment-dose to prophylactic-dose anticoagulation after completing full treatment in the setting of an ongoing risk factor, such as malignancy, should be made on a case-by-case basis.

Medication

The same considerations used to choose between a DOAC and enoxaparin for treatment also apply when selecting prophylaxis.

Dosing

Rivaroxaban/Apixaban/Dabigatran: same dose as treatment dose in children. For children considered adult size, rivaroxaban is 10mg once daily and apixaban is 2.5mg twice daily

Enoxaparin: dose is decreased to 0.5mg/kg twice daily. For children considered adult size, enoxaparin can be dosed at 40mg once daily

Rapid Fire Questions

How does management change for upper extremity DVT?

• Although anticoagulant choice, duration, and diagnostic testing remain the same as lower extremity DVT, the differences come with anatomic malformation. Venous thoracic outlet syndrome requires vascular surgery involvement rather than solely anticoagulation

How does management change for superficial venous thrombosis?

• In general, this does not require anticoagulation. Instead, Dr. Wilson recommends supportive care with warm compresses, NSAIDs, and acetaminophen.
• However, if the location is within 5cm of the deep vein junction, there is concern for propagation to DVT if the clot is not stabilized, and 6 weeks of anticoagulation can be offered

What are the long term consequences of deep venous thromboembolism?

• Although rare, Post Thrombotic Syndrome is a possible complication of DVT. Post Thrombotic Syndrome is chronic venous insufficiency at the site of a prior clot, characterized by pain, swelling, or dilated vasculature. The risk is generally proportional to the clot burden. However, there is no data to support thrombectomy to prevent Post Thrombotic Syndrome
• Treatment for Post Thrombotic Syndrome is strictly supportive, including compression, physical therapy, and pain management

How accessible are DOACs? Will insurance companies pay for DOAC for VTE?

• In the United States, most formularies will cover DOACs for VTE. However, those without insurance cannot afford these medications at full price.
• Dr. Wilson is currently working on research identifying how social determinants of health barriers are affecting VTE outcomes. 

What are the management recommendations when anticoagulation is contraindicated?

• Dr. Wilson recommends supportive care with short interval repeat imaging to evaluate for clot propagation. Then the goal is to restart anticoagulation whenever the risk has subsided. Most children have a temporary contraindication to anticoagulation.
• IVC filters are only recommended when the clot burden is high and the patient is sick, where a new pulmonary embolism would lead to cardiorespiratory collapse. IVC filters are inserted in the IVC by interventional radiology, and should be removed as soon as anticoagulation is safe to give again.

Should a central line be pulled when a clot is attached?

• If the central line is functioning, Dr. Wilson recommends keeping the central line in place and treating with anticoagulation
• If the central line is no longer functioning or ready to be removed, Dr. Wilson recommends removing the line with a minimum of 6 weeks of anticoagulation from initial diagnosis. 

Is anticoagulation contraindicated in patients with cerebral sinus venous thrombosis (CSVT)  with an associated intracerebral hemorrhage?

• If the radiologists are able to characterize the bleed as secondary to venous congestion from the CSVT, Dr. Wilson recommends treating with anticoagulation

Is anticoagulation recommended in Lemierre’s Syndrome?

• Lemierre’s Syndrome is the development of internal jugular (IJ) thrombophlebitis in the setting of oropharyngeal infection. Dr. Wilson recommends anticoagulation (minimum of 6 weeks) because children tend to tolerate it well, and there is little data able to compare antibiotics alone vs antibiotics and anticoagulation together.

Are there any classic mimickers of DVT?

• The classic mimicker of DVT is Post Thrombotic Syndrome. The patient will experience similar symptoms, but repeat imaging is negative.

Goal

Listeners will explain the evaluation, treatment, and duration of anticoagulation for pediatric DVT to improve both acute inpatient management and outpatient counseling

Learning Objectives

After listening to this episode listeners will…  

1. Recall the classic presentation of DVT in children, distinguish deep from superficial veins of the extremities, and identify venous duplex ultrasound as the diagnostic standard.
2. Identify the goals of anticoagulation as well as the indications and contraindications for treating a pediatric venous thrombosis.
3. Distinguish provoked from unprovoked thrombosis and apply that distinction to determining duration of anticoagulation.
4. Compare direct oral anticoagulants, low molecular weight heparin, and warfarin, including situations where each is preferred or avoided.
5. Recognize when secondary prophylaxis is indicated and how prophylactic dosing differs from treatment dosing.
6. Counsel patients and families on bleeding risk, activity restrictions, and medication precautions while on anticoagulation.

Disclosures

Dr Wilson reports no relevant financial disclosures. The Cribsiders report no relevant financial disclosures. 

Citation

Masur S, Wilson H, Chiu C. “#192: Live! The Clot Thickens: DVT and DOACs in Children”. The Cribsiders Podcast. https:/www.thecribsiders.com/ September 23, 2026.