An embolism happens when an object or substance travels through the bloodstream and becomes lodged in a blood vessel. The trapped material is called an embolus.
An air embolism is an air bubble trapped in a blood vessel.
When an air bubble travels along an artery, it moves through a system of blood vessels that gradually become narrower. At some point, the embolus will block a small artery and cut off the blood supply to a particular area of the body.
How serious is it?
The seriousness of the blockage depends on which part of the body the artery supplies blood to. If the embolism stops blood getting to the brain, tissue in the brain will be starved of oxygen and die. This can cause permanent brain damage.
The symptoms of an air embolism depend on where the blockage occurs. An air embolism in an artery to the brain, for example, causes symptoms similar to those of a stroke, including confusion, partial paralysis, seizures or loss of consciousness. See Symptoms, above, for more information.
How does an air embolism happen?
An air embolism can happen when a scuba diver runs out of air and holds their breath while they come up to the surface. It can also happen if a diver surfaces too quickly. It is the leading cause of death among divers.
Air embolism from other causes, such as surgery or a chest injury, is rare (see Causes, above).
How is it treated?
The only effective treatment for air embolism is immediate recompression treatment in a hyperbaric chamber (see Treatment, above). This reduces the size of the air bubbles inside the body and restores normal bloodflow and oxygen to the tissues.
