Alternate Names : Decompression Illness, Caisson Disease, The Bends
Decompression sickness takes place when sudden pressure changes in the environment cause gases that are dissolved in the blood and tissues to form bubbles of gas. These bubbles then block the flow of blood and can produce pain and other symptoms, even death.
What is going on in the body?
When a deep-sea or scuba diver moves from deep to shallow water, he or she moves from a high-pressure environment to a low-pressure environment. When people breathe air under high pressure (for example from a scuba tank while deep-sea diving), they take in increased amounts of gases from the compressed air. These gases dissolve in the blood and tissues and slowly build up. The only way some of these gases can leave the body is through the lungs. However, this process takes time. If a diver rises too quickly to the surface of the water, the pressure may not be high enough to keep the built-up gases dissolved. This can cause bubbles to form in the blood and tissues and decompression sickness to develop.
The gas bubbles that form can block blood flow and cause increased pressure inside tissues of the body. This results in pain and other symptoms. If left untreated, this condition can lead to organ damage and even death.
What are the causes and risks of the disease?
Decompression sickness can be seen in:
scuba divers who rise too quickly after diving in deep water
those who go quickly from a lower to a higher altitude
those who exit from a high pressure or hyperbaric chamber
For scuba divers, conditions which increase the risk for decompression sickness include:
dives deeper than 30 feet
multiple dives in a short period of time
flying on an airplane shortly after diving