Ear Barotrauma
Authors: Unknown
DOI / Source: http://www.divingmedicine.info
Date: Unknown
Reading level: Beginner
Why This Matters for Freedivers
Ear injuries are one of the fastest ways to end a season—and some inner ear injuries can be permanent—so this is “must-know” safety knowledge, not trivia. The big practical takeaway is simple: equalise early, equalise often, and abort the dive at the first sign your ears aren’t clearing easily, rather than trying to push through or “yo-yo” your way down.
Synopsis
This chapter is a very practical guide to ear barotrauma—the most common diving injury—and why it happens. It starts by mapping the ear in a way divers can actually use: the outer ear canal, the middle ear space (an air pocket behind the eardrum), and the inner ear (hearing + balance, filled with fluid). The key problem is simple physics: as you descend, pressure rises and the air in the middle ear compresses. If you don’t replace that air through the Eustachian tube (equalising), the eardrum gets pushed inward, pain builds, and the middle ear lining swells and can bleed. The chapter notes this can start at very shallow depths—around 1–2 metres—which is why “I’ll equalise later” doesn’t work. 
It also covers a mistake freedivers still make: external ear squeeze. If the ear canal is blocked (tight hood, wax, exostoses, ear plugs), the trapped air space compresses and can bruise the canal and distort the eardrum—sometimes from as little as 2 metres—and it clearly warns not to wear ear plugs for diving (page 3). 
The best part is the prevention section because it’s actionable. The author hammers “equalise ahead of the dive”: equalise on the surface before descending, then equalise frequently (especially near the surface where volume changes are biggest), and never push through pressure because swelling makes the Eustachian tube lock up and can make equalising impossible (pages 7–9). It compares techniques: Valsalva is effective but should be gentle; Toynbee (pinch + swallow) can help but is often weaker; BTV (voluntary tube opening) is ideal if you can learn it. It warns about the “yo-yo” habit (descending/ascending repeatedly): it can let the middle ear fill with fluid and blood and seem to reduce pain while you’re actually injuring yourself (page 10). 
Finally, it explains why some ear problems are not just painful but dangerous: reverse squeeze on ascent (air can’t escape, causing pressure, pain, and vertigo), and inner ear barotrauma (tinnitus, hearing loss, vertigo) including round window rupture/fistula, which can cause permanent hearing damage and needs urgent medical assessment (pages 11–13).
Abstract
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