All about the small device (Vena Cava Filter) that stops blood clots from reaching the lungs

Do you know how dangerous it is if a blood clot forms in the veins of your body, especially in your legs, and gets stuck in your lungs? In medicine, we call this a 'pulmonary embolism'. This can even be life-threatening. So today we are going to talk about a small but very important device that is used to prevent such a dangerous situation.

Simply put, what is this Vena Cava Filter?

A Vena Cava Filter is a small metal device. More precisely, it's like a small mesh, or filter. Its main function is to catch blood clots traveling through the veins of the body and stop them from traveling to your lungs.

There are two main types of blood vessels in our body.

• Inferior Vena Cava (IVC): This carries blood from the lower parts of the body (such as the legs and abdomen) to the heart.
• Superior Vena Cava (SVC): This carries blood from the upper part of the body (such as the head and arms) to the heart.

This filter is mostly placed in the Inferior Vena Cava (IVC) , a large vein that carries blood from the lower body. That is why these are also called `(IVC filters)`. To put it in the simplest example, think of it like we put a filter in a water pipe. We allow the water to flow through without any obstruction, but the dirt in the water remains in that filter. This filter does the same thing. While it allows the blood to flow to the heart without any obstruction, it catches the dangerous blood clots that come with it.

What kind of people need this filter?

Not everyone needs this. A doctor may recommend this filter for a few specific reasons. You may be considered for this if you have a blood clot in your veins (Venous Thromboembolism or VTE) and one or more of the following conditions:

Are there types of these filters?

Yes, there are mainly two types.

1. Permanent Filters: Once inserted, these types of filters are not removed. They last a lifetime. These are usually placed in people who cannot take any blood-thinning medications and who are at high risk for long-term complications.

2. Temporary/Retrievable Filters: These are placed in people who are at temporary risk. For example, after major surgery. Once the risk is gone and blood thinners can be started again, these filters are surgically removed.

What happens before surgery?

Okay, now let's say the doctor decides to put this filter on you. There are a few things you need to prepare before that.

• Your doctor will ask about your complete health history. You will need to give a full description of all medications you take (even vitamins).
• Some medications may need to be stopped a few days before surgery. For example:
• Anticoagulants
• Aspirin
• Painkillers (NSAIDs)
• The doctor will tell you exactly how many hours before surgery you should stop eating and drinking. Usually, you will be asked to stop eating 8 hours before and drinking 2 hours before.
• You may also have several tests done to check your health, such as blood tests, an `Echocardiogram (echo)`, and an `Electrocardiogram (EKG)`.

How is the surgery performed?

This is not a major surgery to be afraid of. It is called a 'minimally invasive' procedure. That means there are no major incisions. It can usually be completed in about an hour.

Here's how it happens:

1. First, a saline tube (IV) will be connected to a vein in your arm.

2. You will be given a sedative to keep you calm and relaxed.

3. Next, the area where the filter will be inserted (in the neck or groin) is cleaned and only that area is numbed .

4. The doctor makes a small incision in the numb area and inserts a thin tube called a catheter into the vein.

5. Then, using a type of X-ray called ``Fluoroscopy,'' this tube is guided exactly to the IVC vein. Sometimes, a special liquid called ``contrast material'' may be injected through this tube to make the vein more clearly visible.

6. Once in the correct location, the filter is inserted into the vein through the catheter. It opens up inside the vein and attaches to the walls of the vein.

7. When the work is finished, the catheter is taken out and a small bandage is placed over the incision to close it.

What happens after surgery?

After the surgery, you will need to stay in the hospital for a few hours. The medical team will monitor your heart rate and breathing, and will give you painkillers if you are in pain.

In most cases , you can go home the same day as your surgery . However, you cannot drive yourself, you must be accompanied by a friend or family member. There may be some bruising and discomfort at the incision site for a few days.

Can you recover soon?

Yes. The filter starts working as soon as you put it in.

• If the filter is placed through a vein in your neck , you can usually resume your normal activities within 24 hours.
• If the filter was inserted through a vein in the groin , you will need to avoid certain things for about two days.

However, your doctor will give you the exact instructions that are relevant to you.

Are there any risks involved?

This is generally considered a very safe surgery. However, as with any medical procedure, there are some very small risks. The chances of these happening are very low, but it's good to be aware of them.

• An allergy to the contrast material used for the test.
• Bleeding or infection at the catheter insertion site.
• Damage to blood vessels.
• Filter fracture.
• The blood may have broken away from the filter and traveled to the heart or lungs.
• Blood clot in the IVC vein (IVC thrombosis).

These things happen very rarely. Your doctor will do everything possible to minimize these risks.

When should you see a doctor?

It's very important to take care of your body when you go home after surgery. If you experience any of the following symptoms, you should call your doctor right away .