Air Embolism

An air embolism (gas embolism) happens when air gets into your blood vessels. It can block blood flow and be life-threatening. The air bubbles can also trigger inflammation, leading to tissue damage.

Most air embolisms happen as a complication of medical procedures, like surgeries or vascular interventions. But they’re rare. Deep-sea divers can develop them, as well, when coming up rapidly to the surface. In this case, pressure changes cause lung damage.

There are two main types of gas embolisms:

• Arterial gas embolism: Air gets into your arteries. They’re rare but life-threatening.
• Venous gas embolism: Air gets into your veins. They’re more common than arterial ones, yet still rare. Most small venous air embolisms don’t cause symptoms or health issues. But large ones can.

Symptoms of gas embolisms

The symptoms of an air embolism can vary depending on which part(s) of your body it affects and the cause. But they’re all signs of a medical emergency. Get help as soon as possible.

Symptoms can include:

• Irregular heartbeat
• Sudden drop in blood pressure
• Rapid, shallow breathing
• Chest pain
• Coughing up blood
• Headache
• Confusion or dizziness
• Vision changes
• Paralysis in one area of your body
• Loss of consciousness

Air embolism causes

Air embolisms mainly happen as a complication of medical procedures. But deep-sea diving and blunt and penetrating chest injuries can also cause them.

Some examples of procedures that can cause air embolisms include:

• Central venous catheterization (like PICC lines and ports)
• Arterial catheterization (for constant blood pressure monitoring)
• Lung biopsy or fluid removal from your lungs
• C-section or other gynecologic procedures
• Cardiopulmonary bypass
• Head and neck surgery, including brain surgery
• Hemodialysis
• Injection of contrast dye for CT scans
• Mechanical ventilation

Risk factors

Surgeries that you get in a seated position put you at a greater risk for an air embolism. These are typically head (brain) and neck surgeries. It has to do with pressure differences between your heart and the area of the surgery, which is above your heart.

In some cases, a large venous air bubble can become an arterial air embolism if it passes through your heart. This is more likely to happen if you have atypical blood flow or openings in your heart, like:

• Right-left shunt
• Atrial septal defect
• Patent foramen ovale

Complications of this condition

Air embolisms that affect arteries in your heart or brain are especially dangerous. They can lead to complications like:

• Cardiac arrest
• Heart failure
• Lack of blood flow to your heart muscle (myocardial ischemia)
• Stroke
• Temporary or permanent neurological issues, like vision changes, movement issues and seizures

If the air embolism isn’t treated or is too large, it can become fatal. Experts estimate that an air embolism is lethal when a volume of 3 to 5 mL of air per kg of weight enters your circulation.

How doctors diagnose this condition

If you develop an air embolism, you’ll likely already be in a hospital because you had a procedure. Your healthcare team will assess your symptoms. They’ll check your vital signs and act quickly to start treatment and monitoring.

In some cases, a provider may use imaging tests during high-risk procedures to monitor for air embolisms.

How is it treated?

Your body can typically get rid of a small venous air embolism. It’ll eventually reach your lungs, become trapped and go away when you breathe. But this isn’t the case for arterial air embolisms.

Air embolisms that cause symptoms need emergency treatment. Specific treatment varies depending on the embolism’s location and the cause. Treatment may include:

• 100% high-flow oxygen through a nasal cannula or hyperbaric chamber
• Moving your body into a specific position
• Maintaining your airway and blood pressure

Your healthcare team may need to give you other lifesaving treatments. You may also need care for any complications that develop, like neurological issues.

What can I expect if I have this condition?

The severity of complications from an air embolism depends on many factors, like:

• The size of the air bubble
• The type of gas (room air, carbon dioxide or nitrous oxide)
• The position you were in when it happened
• The body system(s) it affected
• How quickly you get treatment

Your healthcare team can give you a better idea of what to expect.