Pediatric Thromboembolism Treatment & Management

Updated: Jun 24, 2021
  • Author: Scott C Howard, MD; Chief Editor: Hassan M Yaish, MD  more...
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Approach Considerations

Initial care and evaluation for thromboembolism should occur in a pediatric inpatient ward or the ICU if severe respiratory distress or neurologic deterioration occurs. Management includes assessment of the extent of the thrombosis and clinical consequences, a search for thrombophilic risk factors, and anticoagulation therapy.

The duration of anticoagulation depends on the extent and location of the thrombosis, whether the thrombophilic risk factors have resolved, and, in some cases, the degree of thrombotic resolution after the initial therapy. [5, 6, 20, 21, 22, 23]

Neonatal care

Developmental differences in the hemostatic systems of newborns create difficulties in the management of thromboembolism. In addition, neonates have low levels of antithrombin and plasminogen, which cause relative resistance to heparin and thrombolytic agents, respectively.

Moreover, newborns need 11 times the usual concentration of urokinase given to adults and 5 times the usual concentration of tissue plasminogen activator (t-PA) in order to achieve the same rate of plasminogen activation.


On occasion, surgical thrombectomy may be necessary, especially after major cardiac surgery or if thrombolytic agents fail or are contraindicated, or if a limb or organ are threatened.

Supportive care and symptom management

Pain management should include nonpharmacologic therapy (heating pad, elevation of the affected body part). When analgesics are needed, the selection depends on pain severity; mild pain can be treated with acetaminophen, while severe pain can be addressed with acetaminophen plus a narcotic analgesic.

Nonsteroidal anti-inflammatory drugs are generally safe in anticoagulated patients but should be avoided in patients with thrombocytopenia. These agents can be added to therapy for mild, moderate, or severe pain and may reduce the need for narcotics.


A pediatric hematologist should be involved in the care of all neonates, infants, and children with thromboembolism, and a pediatric neurologist should be involved in the care of children with suspected or proven CNS thrombosis.


Inpatient Care

Admit patients with thromboembolisms to a pediatric or adolescent ward or ICU, depending on their respiratory and neurologic status.

Anticoagulation is begun with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH), followed by oral anticoagulation with warfarin. Children require daily follow-up until their international normalized ratio (INR) is more than 2 on 2 successive days. Monitor the patient's INR more closely than usual if changes occur in the patient’s medications or diet. 

In June 2021, the US Food and Drug Administration (FDA) approved the oral thrombin inhibitor dabigatran (previously approved for adults) for the treatment of venous thromboembolic events (VTEs) in pediatric patients aged 3 months to under 18 years who have undergone at least 5 days of treatment with a parenteral anticoagulant. Another indication is reduction in the risk of recurrent VTEs in this population.

Approval for VTE treatment was based on an open-label, non-inferiority study (DIVERSITY), in which 45.8% of the patients who underwent dabigatran treatment met the composite endpoint (complete resolution of the thrombus and absence of recurrent venous thromboembolism and venous thromboembolism–related death), versus 42.2% of those who received standard-of-care therapy. [24]

In addition, an extension of the study was carried out to assess prevention, the primary endpoints being recurrence of blood clots, major and minor bleeding events, and death (both overall and related to blood clots). Blood clots recurred in 3 patients (1.4%), a rate comparable to that of prior standard-of-care treatments. [25]

Obtain daily CBC, prothrombin time (PT), and activated partial thromboplastin time (aPTT) values while children are inpatients. If LMWH is used, obtain an anti–activated factor X (anti-Xa) level and adjust the dose to achieve a level of 0.5-1 U/mL.

A patient's medication may include heparin or LMWH, [26] oral anticoagulants, thrombolytic agents, and, occasionally, antiplatelet agents (for arterial thrombosis). Avoid giving antiplatelet agents to children receiving anticoagulation unless they are absolutely necessary.


Duration of Therapy

The duration of therapy depends on the underlying problem. Children with mechanical heart valves or recurrent thromboembolism require anticoagulation indefinitely. Children with thromboembolism and persistent risk factors may be treated for 3 months and then switched to low-dose warfarin until the risk factor is no longer present. Uncomplicated DVT can be treated for 3-6 months.

Monitor children who are taking LMWH for more than 4 weeks; obtain a CBC count every 1-4 weeks to look for heparin-induced thrombocytopenia and an anti–activated factor X level (every 2-6 wk once a therapeutic level is achieved). Enoxaparin may accumulate over time, and dosage adjustments may be necessary.

After discontinuation of anticoagulation, reducing subsequent risk factors for thrombosis is an important component of lifelong management. For example, patients with a history of thrombosis should avoid smoking and the use of oral contraceptives that include estrogens (desogestrel, gestodene, or drospirenone). [27]



Vitamin K directly interferes with the effectiveness of warfarin and potentially increases the risk for recurrent thrombosis. Daily intake of foods high in vitamin K, such as green, leafy vegetables, should be kept at a consistent level. For example, patients should eat similar amounts of vitamin-K rich foods each day. The patient or family should inform the physician of any changes in the patient’s diet or medications.

Maternal intake of vitamin K can affect levels in breast milk and cause problems in neonates and infants that are similar to those in other patients who consume vitamin K in food. Supplementation with a consistent amount of formula per day has been recommended. Formula-fed infants should receive formula with the lowest concentration of vitamin K available.

Vitamin K should be removed from parenteral nutrition or a constant, small amount should be used each day. Because regulation of dietary vitamin K intake is very difficult, one study found that daily administration of 1 mg of vitamin K plus a somewhat higher dose of warfarin led to more stable INR values in patients receiving long-term anticoagulation. [28]



Children with thromboembolism are sometimes restricted to bed rest for the first 24-48 hours to decrease the risk of PE. However, this practice has never been shown to reduce the risk of embolization, and adults treated for DVT as outpatients (without bed rest) have been found to have no higher incidence of PE than those treated as inpatients. Children with lower-extremity DVT should be fitted for compression stockings to reduce the risk of postthrombotic syndrome. [29, 30]

Patients should avoid participating in contact sports while they are receiving anticoagulation.

Sexually active female adolescents should use some form of birth control, preferably not oral contraceptives, if they are receiving oral anticoagulants. Warfarin is teratogenic, so women on chronic warfarin therapy must not become pregnant.



For patients receiving oral anticoagulation, monitor the PT and/or INR within 3 days of their discharge from the hospital. Always check the INR 5-7 days after adjusting the dose. After the INR is 2-3 (or 2.5-3.5 in patients with mechanical heart valves) on 2 successive measurements obtained 1 week apart, the monitoring interval can be lengthened to every 2 weeks. In general, the INR is monitored monthly. Children taking warfarin for more than a year should be monitored for decreased bone density.

Point-of-care monitoring of oral anticoagulation may be available for home use or at specialized pediatric anticoagulation clinics. Point-of-care monitoring is especially helpful for children who require indefinite oral anticoagulation as part of treatment for congenital heart disease or inherited hypercoagulable disorders.