Decompression sickness is an illness caused when pressure changes allow inert gas absorbed during a dive to form bubbles in the body. The effects can range from pain and skin symptoms to serious neurological or breathing problems. Understanding the process helps divers recognise potential illness and clinicians assess the need for urgent care.
How do inert gas bubbles form?
At depth, the pressure of the surrounding water raises the pressure of the breathing gases. Inert gas—principally nitrogen in ordinary air—then dissolves into blood and tissues. The amount taken up depends on the pressure exposure and the time spent breathing the gas.
During ascent, pressure falls and the body must eliminate this inert gas through the lungs. If pressure decreases faster than gas can be transported and exhaled, dissolved gas may come out of solution as bubbles. Bubble formation and the body’s response to bubbles are central concerns in decompression physiology.
Decompression sickness is not simply a matter of a bubble blocking a large blood vessel. Bubbles can affect circulation and tissues, and may provoke inflammatory and vascular responses. The location and extent of these effects help explain why symptoms can differ substantially between divers.
Who may be at risk?
Risk is shaped by the whole pressure exposure, not by depth alone. Dive duration, ascent profile, repetitive dives, breathing gas and the time available for inert gas to leave the body all matter. Individual physiology and circumstances can also influence how a given exposure is tolerated.
- Dive profile: depth, duration, ascent and surface intervals affect inert-gas uptake and elimination.
- Gas and pressure exposure: the breathing mixture and the pressure changes involved shape the decompression burden.
- Individual condition: health, exertion, temperature and other circumstances may affect risk and symptom interpretation.
- Symptoms after diving: timing and pattern can inform clinical assessment, but symptoms should not be self-diagnosed.
Decompression procedures are designed to manage gas uptake and release, but no profile can guarantee that illness will never occur. A diver’s symptoms and medical history need to be considered alongside the dive record. Suspected decompression sickness calls for prompt contact with qualified medical services, not a decision based solely on a checklist.
What symptoms can decompression sickness cause?
Possible symptoms include joint or limb pain, unusual skin sensations or changes, weakness, numbness, problems with balance or coordination, and difficulty breathing. Some cases are subtle at first; others involve rapidly apparent or severe problems. Symptoms may arise after surfacing rather than during the dive.
These signs are not unique to decompression sickness. Other conditions can resemble it, and a diver may not have a clear or complete symptom pattern. After a dive, new or unexplained symptoms warrant urgent medical assessment, especially when neurological or breathing problems are present.
Clinical evaluation brings together the exposure history, symptom course and examination. Divers can help by recording the dive profile, breathing gas, ascent and symptom timeline, while avoiding delay in seeking care. A diving-medicine physician should be consulted for medical assessment.
How is decompression sickness treated?
Care begins with recognising a possible diving-related injury and arranging appropriate medical evaluation. Clinicians assess the diver’s condition and decide on management according to the symptoms and circumstances. Suspected serious illness is an emergency; contacting emergency services and specialist diving-medicine support is more important than attempting to manage it independently.
Recompression in a hyperbaric chamber is an established treatment approach for decompression sickness. Increased pressure can reduce bubble volume, while breathing oxygen under controlled conditions supports inert-gas elimination and oxygen delivery. The treatment plan and any additional supportive care are determined by qualified clinicians.
Improvement during treatment does not replace medical follow-up. The illness, its treatment and the diver’s recovery all matter when considering future diving. Return-to-diving decisions should be individualised with a physician experienced in diving medicine.
Why does this subject matter to diving medicine?
Decompression sickness connects basic gas physics with clinical medicine: pressure changes govern inert-gas exchange, while bubble behaviour and tissue responses shape illness. Research in this area contributes to understanding decompression procedures, recognising injury and evaluating treatment. It sits alongside related work on gas kinetics, dive planning, neurological effects and hyperbaric care.
For divers and scientific teams, the practical importance is both prevention and response. Careful planning helps manage exposure, but knowing how to recognise a possible problem and obtain specialist help remains essential. The subject also requires clinicians to interpret symptoms in the context of an underwater pressure history.
Frequently asked questions
Is decompression sickness the same as an arterial gas embolism?
Can symptoms begin after surfacing?
Should a diver wait to see whether symptoms pass?
Citation details
- Repository record: Rubicon Research Repository, handle 123456789/4499
This page is an original summary written by the Rubicon editors from the publication’s bibliographic record. It does not reproduce the paper, its abstract or its data; consult the publication itself for its methods and findings.
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