YouDive educational guide · References checked 30 September 2026 · Independent instructor and medical review pending. This library does not provide certification, individual medical clearance or a dive plan.
Understand the risk
DCS involves problems associated with inert gas coming out of solution. AGE can follow lung overexpansion when gas enters arterial circulation. A diver or buddy should not delay emergency help while trying to decide which diagnosis fits.
DCS, AGE and decompression illness: what connects
DCS
Inert gas-related injury
- Needs diving-medical assessment
AGE
Gas in arterial circulation
- Potentially life-threatening
DCI
Term covering both
- Not a diagnosis to make online
Concept relationships from this lesson. These are discussion points, not a dive profile or emergency treatment sequence. Read the cited sources; qualified review is pending.
Put the knowledge into practice
Learn the distinction for understanding, but report the observations: symptoms, timing and the dive history. Sudden weakness, collapse or breathing difficulty after a dive needs emergency assessment. Even symptoms that improve warrant medical advice.
What to notice and discuss
| Consider | Why it matters | Planning or learning response |
|---|---|---|
| DCS | Inert gas-related injury | Needs diving-medical assessment |
| AGE | Gas in arterial circulation | Potentially life-threatening |
| DCI | Term covering both | Not a diagnosis to make online |
PAUSE & THINK
What would you do?
A diver surfaces confused after a rapid ascent.
Reveal the discussion answer
Activate emergency assistance. Give the responders the dive history rather than debating the label.
Frequently asked questions
Can the dive computer rule out DCI?
No. A profile or lack of alarms cannot exclude an injury in a symptomatic diver.
Sources & further reading
DAN: Decompression illness ↗DAN: Back to basics — diving injuries ↗These sources inform this guide; their organisations have not reviewed or endorsed YouDive.
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