**Recommendations**

Pathophysiology and Clinical Aspects of 58 Venous Thromboembolism in Neonates, Renal Disease and Cancer Patients

Remark: Dosing of IV UFH should prolong the aPTT to a range that corresponds to an anti-FXa level of 0.35 to 0.7 U/mL, whereas LMWH should achieve an anti-FXa level of 0.5 to 1.0

We recommend initial treatment with UFH or LMWH for at least 5 to 10 days (Grade 1B). For patients in whom clinicians will subsequently prescribe VKAs, we recommend beginning oral therapy as early as day 1 and discontinuing UFH/LMWH on day 6 or later than day 6 if the INR has not exceeded 2.0 (Grade 1B). After the initial 5- to 10-day treatment period, we suggest LMWH rather than VKA therapy if therapeutic levels are difficult to maintain on VKA

We suggest children with idiopathic TE receive anticoagulant therapy for at least 6 months, using VKAs to achieve a target INR of (INR range, 2.0 to 3.0) or alternatively usingLMWH

For children with recurrent idiopathic thrombosis, we recommend indefinite treatment with

Remark: For some patients, long-term LMWH may be preferable; however, there are little or

For children with recurrent secondary TE with an existing reversible risk factor for thrombosis, we suggest anticoagulation until the removal of the precipitating factor but for a minimum of 3 months (Grade 2C). In addition, with specific respect to the managementof CVL-related thrombosis: 1.2.8. If a CVL is no longer required, or is nonfunctioning, we recommend it be removed (Grade 1B). We suggest at least 3 to 5 days of anticoagulation therapy prior to its removal (Grade 2C). If CVL access is required and the CVL is still functioning, we suggest that the CVL remain *in situ* and the patient be anticoagulated

For children with a first CVL-related DVT, we suggest initial management as for secondary TE as previously described. We suggest, after the initial 3 months of therapy, that prophylactic doses of VKAs (INR range, 1.5–1.9) or LMWH (anti-FXa level range, 0.1 to 0.3) be given until the CVL is removed (Grade 2C). If recurrent thrombosis occurs while the patient is receiving prophylactic therapy, we suggest continuing therapeutic doses until the

In children with DVT, we suggest that thrombolysis therapy not be used routinely (Grade 2C). If thrombolysis is used, in the presence of physiologic or pathologic deficiencies of

therapy or if VKA therapy is challenging for the child and family (Grade 2C).

to maintain an anti-FXa level of 0.5 to 1.0 U/mL (Grade 2C).

no data about the safety of long-term LMWH in children.

VKAs to achieve a target INR of 2.5 (INR range, 2.0 –3.0) [Grade 1A].

CVL is removed but at least for a minimum of 3 months (Grade 2C).

plasminogen, we suggest supplementation with plasminogen (Grade 2C).

Thrombectomy and IVC Filter Use in Pediatric Patients With DVT.

Use of Thrombolysis in Pediatric Patients With DVT.

Recurrent Idiopathic TE for Children

Recurrent Secondary TE for Children

**Recommendations** 

**Recommendations** 

(Grade 2C).

**Recommendations** 

U/mL 4 h after an injection for twice-daily dosing.

If life-threatening VTE is present, we suggest thrombectomy (Grade 2C).

We suggest, following thrombectomy, anticoagulant therapy be initiated to prevent thrombus reaccumulation (Grade 2C).

In children \_ 10 kg body weight with lower-extremity DVT and a contraindication to anticoagulation, we suggest placement of a temporary IVC filter (Grade 2C).

We suggest temporary IVC filters should be removed as soon as possible if thrombosis is not present in the basket of the filter and when the risk of anticoagulation decreases (Grade 2C).

In children who receive an IVC filter, we recommend appropriate anticoagulation for DVT (see 1.2) as soon as the contraindication to anticoagulation is resolved (Grade 1B).

Pediatric Cancer Patients With DVT

Use of Anticoagulants as Therapeutic Agents

#### **Recommendations**

In children with cancer, we suggest management of VTE follow the general recommendations for management of DVT in children.

We suggest the use of LMWH in the treatment of VTE for a minimum of 3 months until the precipitating factor has resolved (eg, use of asparaginase) [Grade 2C].

Remark: The presence of cancer, and the need for surgery, chemotherapy or other treatments may modify the risk/benefit ratio for treatment of DVT, and clinicians should consider these factors on an individual basis.

Use of Anticoagulant as Thromboprophylaxis

#### **Recommendations**

We suggest clinicians not use primary antithrombotic prophylaxis in children with cancer and central VADs (Grade 2C).
