To describe the indication for a vena cava filter (VCF), the most common and important associated complications, and the practical management of patients who have a VCF placed.Appropriately placed VCFs are designed to reduce the frequency of significant pulmonary embolism (PE) by trapping thromboemboli arising in the deep veins of the lower extremities before they reach the lungs.Use of a VCF should be considered judiciously given the lack of high-quality evidence that they prevent clinically important PE.# 
VCFs are indicated in patients with a recently diagnosed (usually within 4 weeks) acute proximal DVT or acute PE in whom there is a contraindication to anticoagulation. If acute proximal DVT is not present, then a decision on the need for VCF should be taken on a case-by-case basis in consultation with a physician with thrombosis medicine expertise.
VCF placement can also be considered in select hemodynamically unstable patients with acute DVT (in shock or ventilatory support) in addition to other advanced therapies (thrombolysis, thrombectomy, embolectomy) particularly where there is a concern that endovenous intervention may lead to iatrogenic PE. 

# WE DO NOT SUPPORT PLACING

# POST-VCF INSERTION MANAGEMENT:
1) Anticoagulation should be initiated to prevent extension of the DVT as soon as it is safe to do so.
2) Virtually all VCFs should be removed shortly after the patient is able to tolerate appropriate anticoagulation. The longer a filter is left in situ, the lower the success of retrieval and the higher the risk of long-term complications. 3) Retrieval may be most successful if attempted within 9-12 weeks post insertion. More recent filters can be retrieved six or more months after placement.
4) A documented plan for retrieval of the VCF should be made at the time of filter insertion. If a VCF is not removed, the patient requires regular, long-term monitoring of clinical status and filter integrity, in addition to possibly long-term anticoagulation (see below). 5) Maintenance of patients on therapeutic anticoagulation should be considered at the time of retrieval and at experienced centers this has not been associated with increased risk of retrieval complications.

# SPECIAL CONSIDERATIONS:
- Very limited evidence supports the use of VCFs and there is no evidence that filters prevent fatal PE. They are also associated with an increased risk of DVT. - The duration of anticoagulation is generally not affected by the presence of a VCF. Patients require anticoagulation for the appropriate duration for the DVT and not just because they have a filter in place. However, this area is controversial and there is no consensus -some clinicians continue anticoagulation long-term in patients with a VCF while others stop anticoagulants once the patients have completed the appropriate duration of anticoagulation for the DVT. - There are few studies of VCFs in children.  

# Date of Version: 06July2021
Please note that the information contained herein is not to be interpreted as an alternative to medical advice from your doctor or other professional healthcare provider. If you have any specific questions about any medical matter, you should consult your doctor or other professional healthcare providers, and as such you should never delay seeking medical advice, disregard medical advice or discontinue medical treatment because of the information contained herein.