Alternobaric Vertigo with associated panic?

[Ed]

Hi,

I am just getting back into diving as a complement to cruising my sailboat.

I quit SCUBA diving years ago, due to what I think I have just deduced from this board, as chronic "Alternobaric Vertigo with associated panic".

Does anyone know why I never get this when free diving? I can easily descend to 20 ft free to check my anchor and return without incident, but when I do it with SCUBA I get AV on ascent. It seems to be worse very near the surface on ascent. In the range of 2-4 feet deep. It feels like a "surfacing rush" and that I am about to black out. Very scary. Particularly since I will usually be doing this alone.

Are the physics the same? Namely, uneven pressure differentials in the middle ear. I do Valsalva equalization during descent both when free diving and SCUBA diving. But never feel the need to do so on ascent whether free diving or with SCUBA. Yet I get AV when ascending with SCUBA.

Is a possible that continous, "proactive" ear equalization (whether I feel the need to equalize or not) on ascent when SCUBA diving will keep AV at bay?

Thank you,
Ed

 

[TSandM]

I wonder if it has to do with the speed of ascent? I've never free-dived, but I would assume you come up through that shallow region fairly quickly, whereas on scuba, you ascend slowly to avoid decompression problems. That allows you to stay where the ear pressure is unequal long enough to develop symptoms.

 

[shakeybrainsurgeon]

What exactly are you feeling? I can't tell...is it true vertigo (spinning or moving sensation), anxiety, pre-syncope (the feeling before losing consciousness)? A combination of all of these? How long does it last? Do you have residual vertigo, ear pain, lightheadedness or ear ringing after surfacing?

 

[Kevrumbo]

Actually that's quite true in both cases --I've had Alternobaric Vertigo in Free Diving and Scuba. In Free Diving, I just return to the surface and deal with "the spinning Universe" up there until it passes.

At depth on Scuba (and switching gas trying to hold level on a Deco Stop), that's an entirely different and dangerous experience all together. . .

 

[knotical]

Is a possible that continous, "proactive" ear equalization (whether I feel the need to equalize or not) on ascent when SCUBA diving will keep AV at bay?

Yes. If it is alternobaric vertigo, and not something else, your suggested proactive equalizing should help. Avoid techniques that increase pressure in your middle ears, such as Valsalva, etc. Instead either use passive techniques such as yawning, swallowing, jaw thrust, etc. or use an active technique like pinching your nose and inhaling gently.

As you suggest, equalize early and often, even as early as the start of your ascent.

You might not experience it on 20 foot free dives because the pressure change is not as great as on deeper scuba dives.

 

[DocVikingo]

Hi Ed,

The answers to shakeybrainsurgeon's questions should prove informative, although we still may not come up with a definitive answer.

In the meantime, one hypothesis is the number of times the Valsalva maneuver is conducted during a SCUBA dive relative to a 20' free dive. On such a free dive the individual may clear a few times on descent; over the course of even a modest SCUBA dive, say to a max depth of 70' with a total bottom time of 50 minutes, equalization is performed many times.

Repeated pressurizations can cause fluid production within the middle ear space. Given differential drainage of this fluid, perhaps as a result of differential Eustachian tube anatomy or function, unequal pressures across the two ears would develop. The outcome could be alternobaric vertigo to which the diver responds with marked anxiety.

If this is the case, it may be helpful to equalize very gently using a technique other than a pressurization maneuver like the Valsalva, for example the Toynbee (pinching the nostrils, closing the mouth and swallowing).

As regards "proactive" ear equalization on ascent, this may prove beneficial. However, rather than using a pressurization technique, it might be best simply to swallow frequently.

In any event, as it now stands this is a very risky situation, made even more so given that the person usually will be diving solo. The prudent diver will not expose himself to such peril until the problem is resolved.

Regards,

DocVikingo

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.

 

[Ed]

What exactly are you feeling? I can't tell...is it true vertigo (spinning or moving sensation), anxiety, pre-syncope (the feeling before losing consciousness)? A combination of all of these? How long does it last? Do you have residual vertigo, ear pain, lightheadedness or ear ringing after surfacing?

Hello all,

Bascially a combination (I have no experience with pre-syncope). I recently tested myself at Catalina Island playing around in only 10-15 of water off the beach. I stayed along the bottom for about 20 mins and then ascended and experienced this AV sensation at about 4 feet from the surface. It is transient, about 10 seconds of so. I relaxed and let it pass. There is no residual effect. Maybe a little lightheadness after surfacing. It is not associated with any ear pain. Or even any sensation of middle ear pressure. I wonder if I have built an unfortunate link between this feeling of vertigo and the feeling of panic. Sort of feeding off each other. If I knew that the vertigo would not really result in unconsiousness, that would probably go a long way towards learning to live with it. Sounds like no one is in favor of Valsalva equalization, so I will knock that off and try the other techniques.

Forewarned that this is a risky situation now, I will try to get to the bottom of this until diving again. Any recommendations for "solving" the problem?

Thanks to everyone.

 

[TSandM]

I'm still a little unclear as to what the symptoms are. You use the term vertigo, but say you feel like you are going to pass out, and those are two different things. Vertigo is a very clear sense of spinning or motion. (I ask patients, does it feel like when the vertical hold on a TV set goes out?) Presyncope is a lightheaded feeling, as though one is going to lose consciousness.

Vertigo is most often related to some inner ear issue, or in diving, sometimes to loss of visual references. Presyncope is a much more difficult symptom to sort out. The conditions which cause vertigo almost never put one at risk for a loss of consciousness, but presyncope can precede blacking out. Vertigo underwater, however, can result in disorientation and loss of buoyancy control, as I know all too well from personal experience, and is definitely not something I'd want to have happen when solo diving (although if it only happens around four feet underwater, you're unlikely to come to great harm).

 

[Ed]

More lightheadedness than spinning or motion. So Presynscope? Bummer. What is it about someone's physiology that might predispose them to this by breathing compressed air even at shallow depths? Is Presynscope triggered by the same middle ear pressure imbalance that causes vertigo? BTW when younger I used to freedive alot spearing fish and would hyperventilate to try and increase bottom time. All without incident. I have never fainted or blackedout in my life.

 

[TSandM]

Presyncope generally doesn't have anything to do with the inner ear. It can be caused by things that range as widely as low blood sugar, low blood pressure, heart rhythm disturbances, dehydration, low oxygen levels, anemia . . . Anything that interferes with the supply of oxygen to the brain can do it. Sometimes people FEEL like they're going to pass out when there is nothing we can find wrong with them.

I wonder if, in your case, you're retaining a lot of CO2 on ascent. Do you tend to slow your breathing coming up near the surface? It's really strange that this only happens at the very end, close to the surface.