Dysbarisms

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What are dysbarisms?

A collection of illnesses resulting from changes in ambient air pressure, to which an individual cannot readily adapt. Dysbarisms include barotrauma, decompression sickness (DCS), arterial gas embolism (AGE), nitrogen narcosis, and oxygen toxicity.

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Who is at risk of developing dysbarisms?

Astronauts, aviators, compressed air workers (e.g., caisson workers, tunnel workers, hyperbaric chamber observers), and scuba divers.

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What is barotrauma?

Trauma due to a failure to equalize pressure between an air-containing space and the environment. Barotrauma that occurs during descent is known as a “squeeze.” A “reverse squeeze” or “reverse block” is experienced upon ascent. Anatomic structures frequently involved include the ear, sinuses, teeth (barodontalgia; air in dental caries or beneath fillings), lungs, and intestines. Facial injury (mask squeeze) results from a faulty mask seal, which does not allow for pressure equalization between the mask and the surrounding environment during exhalation. Although rare, cutaneous injury (suit squeeze) may appear if folds develop in a diver’s wet/dry suit. During descent, these folds create pressure against the skin, which cannot be mitigated.

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