Trauma patients have a high risk of developing fatal blood clots, but a recent IVC filter study illustrates that the medical device is not an effective way to improve survival.
IVC filters are cage-like medical devices designed to capture and prevent blood clots from reaching the heart and lungs. The controversial implant is regularly used as a preventative, or prophylactic, method in trauma care. IVC filters work to prevent DVT, PE and VTE, defined by the Global Thrombosis Day Movement as:
- Deep vein thrombosis (DVT): A blood clot that forms in a deep vein (usually in the leg).
- Pulmonary embolism (PE): A blood clot in the lungs. PE occurs when a DVT breaks free from a vein wall, travels to the lungs, and blocks some or all of the blood supply to the lungs. PE can often be fatal.
- DVT + PE = Venous thromboembolism (VTE): DVT and PE are collectively referred to as VTE.
IVC Filter Study: DVT
Published in Oct. 2015, the study titled "Prophylactic Inferior Vena Cava Filter Placement Does Not Result in a Survival Benefit for Trauma Patients," examined the benefit of implanting an IVC filter after traumatic injury. This research comes at a time when preventative IVC implantation has risen without clear data confirming safety and effectiveness of the treatment.
It was a joint effort between the University of Michigan Department of Surgery, Michigan State University College of Human Medicine and the Covenant Healthcare Department of Surgery. The researchers adjusted the risk factors and compared mortality rates from 2010 to 2014.
Researchers found that preventative IVC filter placement increased the risk of DVT, concluding that "High rates of prophylactic IVC filter placement have no effect on reducing trauma patient mortality and are associated with an increase in DVT events."
Though a large number of trauma patients only require a short-term IVC filter, the device can be extremely difficult or impossible to remove. The FDA recommends retrieving IVC filters as soon as the risk of PE has subsided to limit complications.
In addition to an increased risk of DVT, IVC filters can also migrate and pierce essential organs. Despite the dangers, thousands will be implanted with an IVC filter each year.