Volume 194 - Issue 1
Inferior vena cava filters in trauma patients: who is responsible for their removal?
Authors: Lachlan M Batty, Jim Koukounaras and Stuart M Lyon
Med J Aust 2011; 194 (1): 49. || doi: 10.5694/j.1326-5377.2011.tb04151.x
Published online: 3 January 2011
Published online: 3 January 2011
To the Editor: We read with interest the letter by Baschera et al1 regarding the retrieval of non-permanent inferior vena cava filters (IVCFs) in trauma patients.
With the advent of retrievable devices, there has been a renewed interest in the use of prophylactic IVCFs after trauma. Retrievable IVCFs are a particularly attractive option for trauma patients, who are often young, with only a transient predisposition to develop venous thromboembolism (VTE). They theoretically provide prophylaxis against pulmonary embolism (PE) in high-risk patients for whom chemoprophylaxis is contraindicated, while avoiding long-term complications associated with permanent IVCFs.
However, we share the authors’ concern about low retrieval rates of IVCFs due to loss of patients to follow-up.2,3 The decision to place an IVCF in a patient who has undergone trauma is based on a risk–benefit ratio. If such decisions are made on the presumption that IVCFs will be retrieved, while in practice many IVCFs are not retrieved, the increasing popularisation of retrievable filters may be under false pretences.
At our institution, a level 1 trauma centre, all IVCFs are inserted by interventional radiologists under fluoroscopic guidance. At the time of insertion, patient and device details are entered into a purpose-built IVCF database that is run and maintained by the Department of Radiology. At this time, a follow-up appointment is also booked for the patient to attend the IVCF outpatient clinic run by the interventional radiologists. Here, ongoing VTE risk factors are evaluated and the timing of IVCF retrieval is determined.
The timing of IVCF retrieval after trauma is controversial, and the occurrence of PE after retrieval is well documented. The risk period for PE after trauma is difficult to quantify, but likely to extend beyond the discharge date for many patients, especially if ongoing surgery is scheduled. For this reason, our practice is to retrieve IVCFs in the outpatient setting 3–4 months after injury.
Prolonged IVCF dwell times must be balanced against the increasing difficulty of retrieval because of IVCF endothelialisation, but we feel that a timeframe of 3–4 months does not compromise retrieval rates. Successful retrieval of filters has been reported up to 317 days after insertion.4 As in the case described by Baschera et al,1 it is not uncommon to find a clot in the filter at the time of attempted retrieval, for which multiple causes have been proposed.5 In this situation, it is our practice to rebook patients for a repeat cavogram and second retrieval attempt after therapeutic anticoagulation for 1–2 months.
Competing interests
Stuart Lyon has a consultant agreement with Cook Medical, which manufactures vena cava filters.
References
- Baschera D, Sebunya JK, Zellweger R. Inferior vena cava filters in trauma patients: who is responsible for their removal? Med J Aust 2010; 193: 245.
- Karmy-Jones R, Jurkovich GJ, Velmahos GC, et al. Practice patterns and outcomes of retrievable vena cava filters in trauma patients: an AAST multicenter study. J Trauma 2007; 62: 17-24. 0_i1095412
- Smoot RL, Koch CA, Heller SF, et al. Inferior vena cava filters in trauma patients: efficacy, morbidity, and retrievability. J Trauma 2010; 68: 899-903. 0_i1095414
- Binkert CA, Bansal A, Gates JD. Inferior vena cava filter removal after 317-day implantation. J Vasc Interv Radiol 2005; 16: 395-398. 0_i1095416
- Simon M. Vena cava filters: prevalent misconceptions. J Vasc Interv Radiol 1999; 10: 1021-1024. 0_CBBFHDJE