We often hear the terms DCS and DCI, and DAN AP predominantly uses DCI when we discuss diving incidents, but do you know why we use this term instead of DCS?
Decompression Sickness (DCS)
DCS is a disease caused by freed gas (bubbles) in a diver’s tissues and circulation that occurs when the amount of at-depth dissolved gas in a diver’s tissue exceeds the capacity of the tissues to hold gas at the new, lower ambient pressure. Symptoms may include itching, rash, joint pain, muscle aches or sensory changes such as numbness and tingling. More serious symptoms include vertigo, muscle weakness, paralysis or disorders of higher cerebral function, including memory and personality changes.
Decompression Illness (DCI)
DCI encompasses both decompression sickness (DCS) and arterial gas embolism (AGE). The term DCI is used because the signs and symptoms of DCS and AGE can be similar and because recompression is the treatment for both.
Arterial Gas Embolism (AGE)
AGE is a condition caused by gas in the arterial circulatory system originating from lungs. In divers, this may result from a rapid ascent without exhalation, which causes overexpansion of the lungs and pulmonary barotrauma. The organ most often affected by gas emboli is the brain; usual signs and symptoms include rapid onset of stroke-like symptoms immediately or within minutes upon reaching the surface. An AGE may occur in water as shallow as 1.5m after taking one breath of compressed gas followed by a breath-hold ascent.
You can find more information about DCI, and a range of other medical issues, at DAN Doc.