Fat Embolism Syndrome

What is fat embolism syndrome?

Fat embolism syndrome is a condition where particles of fat get into your bloodstream and block blood flow. Blockages can affect your brain, lungs, skin and other areas. This condition is rare and usually isn’t serious, but it can be dangerous when it's severe.

What's the difference between a fat embolism and a pulmonary embolism?

Breaking down the differences between a pulmonary embolism and a fat embolism starts with defining some key terms.

• Embolism: A blockage in a blood vessel. These can happen because of blood clots, air bubbles or bits of fat circulating in your blood.
• Fat embolism: A blockage in a blood vessel made up of one or more particles of fat.
• Pulmonary embolism. A blockage in a blood vessel in your lungs.

While blood clots are far more likely to cause pulmonary embolism, fat embolisms can still cause pulmonary embolisms, too (which are life-threatening medical emergencies). Fat embolism syndrome also causes problems with breathing even when it doesn’t cause a pulmonary embolism.

Who does it affect?

A fat embolism can happen to anyone, but they are extremely rare in children. This condition is most likely to happen when you fracture your pelvis (the bone that forms your hips) or the long bones in your body.

In rare cases, other conditions or circumstances can also cause this condition. Some examples include:

• Knee or hip replacement.
• Severe burns.
• Receiving CPR.
• Bone marrow biopsy or transplant.
• Acute pancreatitis.
• Fatty liver.
• Liposuction.
• Sickle cell anemia.

How common is this condition?

While a fat embolism can happen every time you fracture a bone, it’s usually not enough to cause a problem.

In people with an isolated break of a long bone like the femur, fat embolism syndrome happens in between 0.5% and 2% of all cases. When it involves multiple broken bones, especially fractures in your pelvis, this condition happens in between 5% and 10% of cases.

How does this condition affect my body?

Fat embolism syndrome can be a dangerous condition at more serious levels because it can make it hard for you to breathe. At more severe levels, this disease is sometimes deadly because of how it affects your lungs, or because the impact on your lungs puts so much strain on your heart that your heart fails.

What causes the condition?

A fat embolism is when one or more droplet-like particles of fat enter your bloodstream and block circulation through some of your blood vessels. Fat emboli (the term for more than one) form anytime you break a bone, but they’re usually too small to cause any blockages. That means it’s rare for fat emboli (pronounced EM-bo-lye) to cause problems.

Fat emboli are much more likely to cause a problem when they happen after you break certain bones. About 95% of cases involve fractures of the pelvis or long bones in the body, especially the femur (thighbone), tibia (shinbone) and fibula (which runs behind the tibia) bones in the legs.

Most of the time, the particles of fat in your bloodstream can get stuck near the surface of your skin in smaller blood vessels called capillaries, causing a rash and other mild symptoms. Fat emboli can also affect small vessels in critical areas like your heart, brain, eyes or lungs, causing severe and life-threatening problems.

Three specific effects are usually enough for a doctor to diagnose this condition (though a diagnosis is also possible without all three). Those include a distinctive rash on your skin and effects on your brain and lungs.

What are the symptoms?

Fat embolism syndrome usually happens within 2 to 3 days after a major bone break or other types of trauma. But it can happen as soon as 12 hours after an injury. The main symptoms include the following:

• Trouble breathing. Struggling to breathe or breathing fast are common with fat embolism syndrome. These symptoms usually develop before others.
• Mental state changes. Fat embolism syndrome can affect how your brain works, causing headaches, confusion, personality changes, or making you unresponsive or slow to respond. It can also involve seizures or going into a coma.
• Petechial rash. Petechiae (pet-ee-key-ay) are small bruise-like spots on your skin. They happen when blood vessels called capillaries burst or break just underneath your skin’s surface. These spots usually appear on your head, neck, chest and arms. They can also happen on the inner side of your eyelids and the inside of your mouth.

Other possible symptoms include:

• Fast heartbeat.
• Fever.
• Jaundice (a liver condition that causes yellowing of your skin or the whites of your eyes).
• Vision changes.

Doctors may also test for the following clinical signs. These are changes that diagnostic and lab tests can find but that you can’t feel as symptoms:

• Low blood oxygen saturation.
• Anemia.
• Kidney problems.
• Vision problems.
• Low platelet count and other changes in your blood chemistry.

Is it contagious?

Fat embolism syndrome isn't contagious.

How is it diagnosed?

At this time, there’s no universally accepted standard for diagnosing this condition. Because of that, doctors make this diagnosis based on your symptoms, a physical exam, diagnostic and lab testing.

The physical exam involves a doctor looking at your body for signs and symptoms of potential medical problems. They may also listen to your heart and breathing with a stethoscope.

The three main symptoms of this condition, trouble breathing, mental status changes and petechial rash, are signs and symptoms that are usually visible. That means in many cases, especially those that are more severe, a physical examination is enough to diagnose this condition.

What tests will be done to diagnose this condition?

Testing for this condition can include any of the following.

• Imaging studies: Doctors may take X-rays, computed tomography (CT) scans, or magnetic resonance imaging (MRI) scans of your head or chest. These are likely because doctors will want to rule out life-threatening problems like stroke or pulmonary embolism. The scans can help rule out those conditions and help confirm a diagnosis of fat embolism syndrome.
• Diagnostic tests: Diagnostic tests may happen when symptoms of fat embolism syndrome affect your heart. Examples include an electrocardiogram, a test that measures electrical activity in your heart or a skin biopsy to look for signs of fat particles blocking capillaries in your skin.
• Lab tests: These tests will look for key changes in your blood chemistry and look for traces of fat particles in your blood, urine or sputum (mucus you cough up).

How is it treated, and is there a cure?

There’s no cure for fat embolism syndrome, and there’s no standard treatment plan for cases of the condition. Treatments for fat embolism syndrome can include medications, life-supporting devices and treatments to prevent further complications.

The main goal with this condition is providing supportive care. That means healthcare providers focus on treating the symptoms and effects of the underlying disease rather than the disease itself.

What medications/treatments are used?

Possible treatments used with fat embolism syndrome include:

• Corticosteroids. These medications reduce inflammation in your body. Healthcare providers often prescribe them to reduce inflammation, help your lungs and make it easier for you to breathe. However, more research is necessary to verify if this should be a standard treatment for this condition.
• Blood-thinning medications. These can prevent potential blood clots that might happen along with fat embolism syndrome. However, there isn't enough evidence that supports using these in every case of fat embolism syndrome.
• Vena cava filters. These are devices healthcare providers can insert into your veins and guide into place. Once inside your vena cava (the largest vein in your body, which directs blood into your heart), these filters catch clots that might get stuck in your lungs. This prevents a pulmonary embolism or the respiratory effects of fat embolism syndrome.
• Oxygen. This is one of the fastest, easiest treatments that can happen with any kind of respiratory problem. Increasing oxygen supply means your lungs and heart don’t have to work as hard to provide plenty of oxygen to your body.
• Extracorporeal membrane oxygenation (ECMO). Extracorporeal membrane oxygenation (ECMO) is a process that takes blood out of your body and through a special sequence of devices that remove carbon dioxide and add oxygen. The blood then travels back into your body. This therapy can help give your lungs a break so they can recover when you have severe breathing problems from fat embolism syndrome.
• Ventilation. A ventilator is a device that does the work of breathing so you don't have to. It's a common part of treatment for people who have serious and life-threatening breathing problems. This process starts with intubation, which is inserting a tube down the windpipe, and attaching that tube to a ventilator. You are usually sedated during this process to help keep you comfortable.

Complications/side effects of the treatment

Fat embolism syndrome typically doesn’t have any direct complications. However, severe cases can result in long-term effects in your brain, eyes or lungs. However, most people will go on to recover fully. You should ask your healthcare provider about the possible and likely side effects or complications in your case. They are the best source of information because they can tailor that information to your specific circumstances and needs.

Some evidence suggests fat embolism syndrome can put you at a greater risk for problems like deep vein thrombosis or long-term effects on your brain. However, that evidence isn't confirmed, and it will take more research to determine if this is the case.

How to take care of myself/manage symptoms?

Because fat embolism syndrome can cause problems with your breathing and disrupt your brain's normal functions, you shouldn't try to care for it independently. The best thing to do is to go to the hospital and seek medical attention.

How can I reduce my risk for — or prevent — this condition?

Because fat embolism syndrome often follows broken bones, it's very common for people to have broken bones stabilized. This usually involves realigning and immobilizing broken bones, but it can also involve surgery with more severe fractures.

Healthcare providers may also prescribe corticosteroids after a severe fracture to try and prevent this condition from developing. However, more research is necessary to confirm if the benefits from this approach are greater than the potential risks.

What’s the outlook for this condition?

Fat embolism syndrome is deadly in between 5% and 20% of cases, with the death rate trending downward for several years now. The drop in the death rate is largely due to preventive measures and better in-hospital monitoring for those at greatest risk.

Fat embolism syndrome is most dangerous when it causes severe breathing problems or heart failure. The risk for developing either of those problems is highest when this condition is severe or when there are delays in treatment.

In moderate and mild cases, fat embolism syndrome usually resolves on its own and rarely causes long-term effects.

How soon after treatment will I feel better, and how long does it take to recover?

In most cases, fat embolism syndrome isn't a severe condition, and it goes away on its own within a few days. It can take days or weeks for any skin or neurological (brain-related) problems to go away in severe cases. Respiratory problems will usually go away on their own within a year. Respiratory problems that don't get better on their own usually aren't severe enough to need ongoing medical care.

How do I take care of myself?

In general, most people won’t need to take special precautions after fat embolism syndrome. However, it’s important to be careful with any broken bones that led to developing the condition. Re-breaking a bone may cause this condition (if you didn’t have it before) or cause it to happen again.

If you have specific questions about your circumstances and case, your healthcare provider is the best person to guide you on what you can to help yourself as you recover from this condition.

When should I see my healthcare provider?

Your provider will likely recommend follow-up visits and care to monitor any long-term effects related to fat embolism syndrome, but these are rare. Your provider can also tell you the signs and symptoms to watch for that indicate you need medical attention.

When should I go to ER?

You should go to the hospital anytime you have a broken arm or leg. Hospital facilities can best treat these kinds of fractures and help you avoid complications or other problems.

You should also go to the hospital if you have fat embolism syndrome and start having changes in your mental state or any symptoms related to pulmonary embolism.

Mental health change symptoms include:

• Confusion or irritability.
• Feeling lethargic or slow to respond.
• Seizures.

Pulmonary embolism symptoms include:

• Chest pain.
• Trouble breathing, especially if it happens quickly or suddenly.
• Coughing or wheezing (especially if you cough up blood).

A note from Cleveland Clinic

Fat embolism syndrome is a rare condition that usually goes away on its own without long-term impacts. However, it can be dangerous or even deadly in some cases — especially severe cases or those that don't get quick treatment. Fortunately, advances in medical care have greatly reduced the risks from this condition, especially with fast diagnosis and treatment.