difficulty "re-equalizing" after ascent

[adjuster-jd]

I have noticed that I have difficulty equalizing if I have either ascended to the surface or even near the surface and then try to descend again. Initially I an equalize on the initial dive and have no problem equalizing on subsequent dives followed by a surface interval.
Where my problems arise is when I ascend from a dive and immediately try to re-descend or even if I ascend to a shallow depth and then re-descend. I then have trouble equalizing.

An example was this past weekend when I went down to approx 40 feet to set a descent line and affix a hang bottle to the line. When I came back to the surface and tried to go back down to the bottom with the group, I couldnt equalize. After repeatedly trying to equalize unsuccessfully, I removed and replaced my mask at the surface and ultimately was able to equalize.

On later dives of the day, all of which had surface intervals between them, I had no problems equalizing.

Since I am a divemaster candidate, one of my duties is going down and setting up lines, etc and then still being able to dive with the group. Obviously, difficulties equalizing when I have try to re-descend can cause problems in these circumstances.

Anyone have any ideas as to cause of my problems and possible solutions?

Thanks.

 

[Laurence Stein DDS]

I have noticed that I have difficulty equalizing if I have either ascended to the surface or even near the surface and then try to descend again. Initially I an equalize on the initial dive and have no problem equalizing on subsequent dives followed by a surface interval.
Where my problems arise is when I ascend from a dive and immediately try to re-descend or even if I ascend to a shallow depth and then re-descend. I then have trouble equalizing.

An example was this past weekend when I went down to approx 40 feet to set a descent line and affix a hang bottle to the line. When I came back to the surface and tried to go back down to the bottom with the group, I couldnt equalize. After repeatedly trying to equalize unsuccessfully, I removed and replaced my mask at the surface and ultimately was able to equalize.

On later dives of the day, all of which had surface intervals between them, I had no problems equalizing.

Since I am a divemaster candidate, one of my duties is going down and setting up lines, etc and then still being able to dive with the group. Obviously, difficulties equalizing when I have try to re-descend can cause problems in these circumstances.

Anyone have any ideas as to cause of my problems and possible solutions?

Thanks.

The cause is actually fairly simple. The solution will vary from individual to individual.

What usually happens is that the tissues surrounding the eustatian tubes can become ingorged with blood and block the free flow of air between the nasal cavity and the middle ear. This is the reason divers are advised to descend feet first rather than head first...in the head first position, you have a column of blood above your years that is nearly as long as your height...and that has some weight which is manifest as increased pressure on the blood vessels in the most dependent part of the body at the time...your head. Descending feet first reverses this tendency.

Next, you may know that it is best to clear early and often. Personally, I actually "pressurize" my ears just before hitting the water and in fact I usually will make sure the ear canals are open by practice clearing long before the dive.

Equalize before you feel you need to.

Go up slightly (ascend) if you experience any difficulty...this both reduces the pressure needed to push the air into the ears AND it reduces the pressure transmitted through the fluids within your system that tend to restrict air movement.

Once you get to your desired depth, the truth of the matter is that you will probably vary your depth through out your dive and you may not be aware that you may not be making adjustments in your equalization. This congests the ear.

It's not so noticable at depth because the percent change in air pressure is slight form most of the dive but once you surface or get within about 10-15 feet of the surface, you may have difficulty descending again.

Some solutions would be as mentioned, extra care in initial equalization, proper attitude during descent, awareness of minor pressure changes that may go without an attempt at equalization. For others, there may be an overlay of allergies, nasal congestion. For this, decongestants and long acting nasal sprays may help (used properly).

My personal experience is that when this happens to me, when I finally get out of the water for my surface interval...even a few minutes for shallower dives, is enough to let me clear successfully again. As the day wears on however, if the congestions persists or gets worse, then you might have to wait extra long or suspend diving for the day.

I'm sure there are other opinions as to cause, effect and treatment so hopefully others will pipe in.

Right now, I'm gettin ready for Katrina!
:06:

Laurence Stein DDS