An intravenous filter, also known as a Greenfield filter, is placed to prevent blood clots from spreading from other parts of your body into your lungs. If there are clots (known as thrombi) in the more proximal parts of your legs (your thighs, for example), these have a certain rate of breaking free and floating downstream, where they can become lodged in your lungs, which is then known as a pulmonary embolus. Thrombi in the deep veins of your legs are especially prone to doing this, and can be life threatening.
Most people will have some form of anticoagulation
to prevent clots from forming, but some people with known clots are not candidates for either clot preventing drugs or clot dissolving drugs, and these people are then considered for placement of a filter. To place the filter, your doctor
will use a needle to access the major veins of your body. Usually, the entry point will be through the groin. The filter itself will then be positioned and deployed relatively simply.
The major issue with regards to recover time is that small entry point of the needle, and then any medical conditions that might have necessitated the filter placement, of course. Please talk to your doctor about this before your procedure.