When a diver ruptures an eardrum, cold water entering the middle ear space on that side often causes dizziness. It also can be quite painful. Upon surfacing, bleeding may be noticeable, as may hearing loss & ringing in the ear/odd sounds. A diver with a ruptured eardrum may experience the sensation of air moving out of the ear upon ascent. On the other hand, a tympanic membrane can rupture without showing any of these features.
However, it seems very unlikely that a diver with a breached eardrum could make repeated dives with such a condition without experiencing any of these signs or symptoms other than a feeling of bubbles coming out of the ear, nor without eventually developing a middle ear infection.
Of course, for such a feeling to arise in both ears as the result of a torn eardrum there would need to be ruptures bilaterally. Not only is it rather improbable that this would have occurred in the absence of a clearly identifiable event, but it is even more improbable that none of the other discussed signs or symptoms would have appeared after continued diving.
Given the sole phenomenon of a sensation of bubbles coming out of the ear upon ascents, it would appear more likely that an inefficiently clearing or congested air space somewhere in the head, such as the middle ear system, is responsible.
This is educational only and does not constitute or imply a doctor-patient relationship. It is not medical advice to you or any other individual, and should not be construed as such. Issues related the ear & diving should be discussed with the diver's personal physician.
Best regards.
DocVikingo
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