What is a Greenfield filter used for in clinical settings?

A Greenfield filter, also known as an inferior vena cava (IVC) filter, is utilized primarily to manage recurrent pulmonary embolisms, especially in patients who have a heightened risk but are unable to tolerate anticoagulation therapy. The primary purpose of this filter is to capture and immobilize thrombi (blood clots) that may dislodge and travel to the pulmonary arteries, thereby preventing potentially life-threatening embolisms.

The insertion of a Greenfield filter is particularly beneficial in patients with a history of venous thrombosis or pulmonary emboli when conventional anticoagulant treatments are ineffective or contraindicated, such as in cases of severe coagulopathy or recent surgery. The device is placed in the inferior vena cava, where it can catch clots before they reach the lungs.

While other options may relate to vascular or circulatory health, they do not accurately describe the specific function of a Greenfield filter in preventing pulmonary complications due to thromboembolic events.