Reviewed and revised 11th November 2013
- filter placed in the inferior vena cava (IVC) to prevent clot passage
- first introduced in the 1960s
- aka vena cava filters (VCF); they can sometimes be placed in the superior vena cava (SVC)
PE prophylaxis in the following settings:
- recurrent PE despite anticoagulation
- life-threatening clot (e.g. hanging iliofemoral DVT or proximal DVT in a patient with limited cardiorespiratory reserve) despite anticoagulation
- anticoagulation contra-indicated
- high risk trauma patients (definitions vary), such as:
— severe TBI
— spinal injury
— pelvic and/or lower limb long bone fractures
- Different types exist
- previously permanent now temporary, reversible devices are preferred
- ‘umbrella’ like device with expandable net-like struts that expand once placed inside the IVC
- new devices are MRI compatible
- modern temporary devices have retrieval mechanisms (e.g. Cook CelectTM has a hook on the tip and can be collapsed into a sheath)
METHOD OF USE
- Placed endovascularly by an interventional radiologist
- access via the femoral or internal jugular vein (rarely an upper limb vein)
- venogram is performed to define the anatomy
- guidewire is inserted under fluoroscopy
- the compressed filter is passed over the wire and sited in the desired location
- usually sited below the renal veins in the IVC (can occasionally be placed elsewhere such as the SVC)
- deployed once position confirmed
- remove as soon as the risk of PE is sufficiently low
- If acute DVT or PE is present, at least 2-3 weeks of anticoagulation should be given prior to IVC filter removal
- do not interrupt anticoagulation prior to IVC filter removal
- for prophylactic IVC filters (no known DVT) get an ultrasound to confirm no DVT is present before IVC filter removal – if DVT is present (including in the filter itself, if considered significant), and the patient is not already on anticoagulation, anticoagulate for at least 2-3 weeks before removal.
- hematoma and/or vessel perforation
- air embolism
- vena caval occlusion with clot (~20% at 5 years) with impaired lower limb venous return and DVT formation
- dislodgement and migration
- device fracture and embolisation (cardiac tamponade and dysrhythmias have been reported)
- vessel erosion
- may paradoxically seed recurrent PEs if high clot burden
- failure to remove (inability or loss to follow up)
- only 1/3 retrievable IVC filters are ever removed!
Different complication rates with different models of IVC filter
- the evidence for IVC filters is very limited, it’s use is largely based on physiological rationale
- The PREPIC (Prevention du Risque d’Embolie Pulmonaire par Interruption Cave) trial (1998), was an open RCT of 400 participants with documented proximal DVT or PE who received concurrent anticoagulation. Eight year follow up was published in 2005.
— Permanent IVC filters prevented symptomatic PE at eight years (15% versus 6% in no filter group)
— No reduction in mortality was seen (this was an older study population with most deaths due to cancer or cardiovascular causes)
— markedly increased incidence of DVT in the filter group (36% versus 28% in the filter group)
— no difference in post-phlebitic syndrome
- Haut et al’s 2013 meta-analysis of 8 controlled studies in trauma patients found a consistent reduction in rates of PE (but with an NNT between 109 and 962!) and fatal PE, but no difference in rates of DVT or overall mortality
- Prassad et al (2013) argue that the history of the IVC filter provides valuable insight into the shortcomings of medical device approval in the United States
References and Links
- Decousus H, Leizorovicz A, Parent F, Page Y, Tardy B, Girard P, Laporte S, Faivre R, Charbonnier B, Barral FG, Huet Y, Simonneau G. A clinical trial of vena caval filters in the prevention of pulmonary embolism in patients with proximal deep-vein thrombosis. Prévention du Risque d’Embolie Pulmonaire par Interruption Cave Study Group. N Engl J Med. 1998 Feb 12;338(7):409-15. PMID: 9459643.
- Haut ER et al. The Effectiveness of Prophylactic Inferior Vena Cava Filters in Trauma Patients: A Systematic Review and Meta-analysis. JAMA Surg 2013 ;epublished November 6th
- Prasad V, Rho J, Cifu A. The inferior vena cava filter: how could a medical device be so well accepted without any evidence of efficacy? JAMA Intern Med. 2013 Apr 8;173(7):493-5; discussion 495. PMID: 23552611.
- PREPIC Study Group. Eight-year follow-up of patients with permanent vena cava filters in the prevention of pulmonary embolism: the PREPIC (Prevention du Risque d’Embolie Pulmonaire par Interruption Cave) randomized study. Circulation. 2005 Jul 19;112(3):416-22. PMID: 16009794.
- Young T, Tang H, Hughes R. Vena caval filters for the prevention of pulmonary embolism. Cochrane Database Syst Rev. 2010 Feb 17;(2):CD006212. PMID: 20166079.
FOAM and web resources
- Doctor Skeptic — Clot filters (2013)
- Medscape — Inferior Vena Cava Filters
- PulmCCM.org — Inferior vena cava filters: debatable benefit; rarely removed (JAMA) (2013)
- PulmCCM.org — Inferior vena cava filters for acute PE and DVT (ACCP Guidelines) (2013)
- Radiopedia — Vena cava filter
Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also the Innovation Lead for the Australian Centre for Health Innovation at Alfred Health, a Clinical Adjunct Associate Professor at Monash University, and the Chair of the Australian and New Zealand Intensive Care Society (ANZICS) Education Committee. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.
After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.
He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE. He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of LITFL.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.
His one great achievement is being the father of two amazing children.
On Twitter, he is @precordialthump.