MEDICAL FAQs

QUESTION

ANSWER

Forget that new winged BCD and twinset. The $500 wetsuit that gives you an hourglass figure and keeps you warm. Even the shiny titanium regulator that delivers only what you need.

Forget them all. You aren't even going to get to 7 metres if you can't equalise. And this depends on a little tube only a few centimetres long. The Eustachian tube.

It's one of the most frequent reasons to consult. A novice diver has "taken to the sport". Buys the neatest gear their credit card will let them, and ends up in a surgery a week after doing the 4 open water dives needed for their initial cert.

"Doc" they say. " I just can't seem to equalise properly and now my ears hurt like hell."

Well the point of this article is to look at the real basics of equalising, why it goes wrong and what we can all do to have clear ears after a dive.

Some basics first. Ear anatomy. The bit that gets bitten by Tyson is of course the outer ear. That's made of 2 parts. The floppy "tragus" where normal folk get an ear piercing, and the harder "pinna", where masochists do. This is connected to the middle ear by the tube you can stick your finger or a pen in when bored at work. This is the external auditory canal. This will fill with water in a dive and doesn't need to be equalised. This canal ends at the ear drum, the dividing line between the outer and middle ear. And it's in this middle ear that things can go so wrong for a diver. The middle ear is air filled. This helps the 3 bones: malleus, incus and stapes transmit sound across the middle ear to the window of the inner ear. Here the bone movement is transmitted into sound by some complex nerve stuff we wont go into now. So we have an air filled cavity in a species that's not supposed to be living underwater any more. As we descend every 10 metres the volume of the air will halve. Thank goodness for the Eustachian tube. It allows us to blow in more air to counter the volume halving as we dive deeper. By pinching the tip of the nose and blowing against that we can push more air up into the tube and into the middle ear. Simple really. But as we all know it doesn't to work out all the time.

If we look at what happens if we didn't equalise we can see the dangers of diving. You wont notice anything for the first few metres. By the 4th metre the volume decrease is managed by the ear drum moving in to the space. Getting deeper the pain sets in from the drums concaving even more and the lining of the middle ear being swollen by the vacuum. Deeper still to 10 metres and the windows between middle and inner ear may begin to be badly affected causing dizziness as the balance centres are given confusing signals.

And deeper still to 20 metres and you may be overwhelmed by pain and then a sudden gushing of water into one or both ears as the drums implode, perforate and the water gushes through. This will equalise you at last, but deafness, dizziness and infection may become a permanent feature.

So why does it seem to go wrong for new divers?

In the pool all is easy. The depths you are at are shallow enough to not cause any discernable pain if you don't equalise properly. Besides that, the sheer novelty of breathing underwater seems to make all else insignificant.

But it's oh so different on the first 4 proper open water dives.

We all know what to do, have had it drummed into us at the pool.

Gear on, buddy check. Giant stride. OK sign in the water. Then the group goes down together with consummate ease.

Yeah, right.

What classically can happen is the new experience has become tinged with a bit of natural anxiety. Thumbs down, you're off. Equalize little and often you have been told. But guess what goes straight out of the window as you realise your weight belt is slipping off, spin to find your buddy, gaze at a barracuda and keep checking depth and your air gauge? Yup, you've forgotten to pop your ears. And with a little bit of overweighting down you go. If by 7 metres you haven't gotten any air up the Eustachian tube, forget it because you wont. The pressure has forced it shut already. That's why you need to ascend a bit and start all over again. Well that's what they tell you to do in training anyway.

However the reality that a first time diver is going to hold up the group, bob on their own with perfect buoyancy at about 4 to 5 metres to clear the ears and then masterfully join the group in a few minutes to do all the skills is remote.

They plummet down frantically contorting as they fail to put any air in the ear, and kneel down to do the regulator retrieval wishing they'd gone paragliding instead.

Next week they are in the surgery trying to sort it out before the small ad goes into the papers offering $1000 worth of kit for half the price.

So let's get it right.

Before you even go near the water, practise equalising. Unless you are a miner or a pilot, the Eustachian tube is a rarely used organ. Exercise it a little. I suggest you pop those ears up to 10 times a day gently for a week before you go.

When you take the first plunge, remember it's little and often. Don't wait to 6 metres and try to blast the air up the tube. Do it in small amounts every few seconds and all will be fine. Always drop feet first as the raised pressure in your thorax and lungs makes equalising a whole lot easier. If it's not working then stop, fin a little up and try gently again. Don't hyperinflate your BCD and rocket up. It's a gentle process as I said. Then slowly go down and join the others.

Easy really.

But if it really isn't your day, what to do?

Well you're just going to have to say no, do the hand signal and go up. Dive over but live for another day.

The reasons for failure are many fold. At the worst case scenario you have a completely dysfunctional Eustachian tube [ETD]. As a rough rule of thumb from experience, if you have a history of glue ear as a kid, problems every time you fly you may well have ETD. This can be linked to a history of allergy or gastric reflux as well. Get that sorted by the doc before trying diving. However if it's not that bad and on the whole you can pop on the plane then there are other reasons for equalizing cock ups. More commonly it's poor technique that is corrected by observing the above procedures. There are some divers I suggest try a medication to see if it will open up the tube before giving it all up. Otrivine and Beconase nasal sprays have been tried to good effect. Sudafed tablets too. These basically shrink the lining of the Eustachian tube, consequently widening it's bore so making it easier to get air up the thing. Some dive manuals say never use these meds. I say try them about an hour or two before a dive if you are having difficulties. I would rather you did that than tried to get down without them if you are going to dive anyway. The chances of them suddenly cutting out on your ascent are remote as they have a reasonably long half life.

But, never use them when you dive on Nitrox or are going to use a high ppO2 on deco stops, as they can increase your sensitivity to oxygen, and thus a fit.

If you do finally manage to get down deep for the first time using one of these meds, then does that mean you always have to use them every time you dive?

Not necessarily. It could be something undiagnosed and fixable by a good dive doc. Nasal polpys. Nasal septum displacement. An allergic reaction to the ships cat, that has caused a bit of over-mucous production. All correctable.

And whilst on the subject of mucous. The commonest reason to get equalisation problems is diving with a cold. I know the manuals all say don't dive with this annoying viral infection.

But I'm a realist. You've just payed out a months wages for the liveaboard to the Burma Banks. Then the sniffing and sneezing starts. "Oh I'd better not dive the whale shark cos the book says I can't." No, 110% of divers go for it. So if you do, do take something to pop open the Eustachian tube or it will be the cotton wool hearing for the next 6 weeks for you.

This has been all about the way down so far. What about the other direction?

If you are unfortunate enough to just about equalise on descent but then find the expanding air wont come out on ascent, then an ear perforation in on the cards. You will know this when you feel a pop and a gush. Cold water will tinkle through into the middle ear and then the back of your throat. See the doc asap. Cover it with antibiotic drops and leave diving well alone for about a month. Always get a check before you dive to see whether it has healed properly. If not, stay dry and even consider skin grafting the drum if it hasn't healed after 6 months. If the hole's closed properly you are fine to dive.

There is some fine quirky ear stuff that's worth knowing too.

A tight hood in one field of medicine may lead to circumcision. In diving medicine it causes an unequalisable pain where the drum is pulled the other way and though you feel your ears pop, it still hurts. Pull the hood off the ears and all will be fine.

Ear wax or cerumen as old docs still call it can create problems. If it is a big thick wedge of wax, the air space between this and the drum can make things feel weird on descent. So if you find you are a tad deaf even before diving get your doctor to have a look inside the canal and syringe as necessary.

Finally there are some innovations to help those who can't equalise.

The makers of Swim-Ear have a nasally inhaled lubricant that promises to make it easier to equalise. Its called Equal-eze and can be worth a try.

But the medal for new inventions must go to the Pro-Ear mask made by Oceanic. 2 tight fitting headphone like contraptions sit over your ears. They create an air space in the outer ear canal as the water can't get in. These spaces are equalised by 2 tubes that run from the face-piece of the mask and equalise the outer canals as you do the middle ear. I know a lot of Instructors that swear by them, so that is your penultimate resort.

The last resort?

Well, here's a new acronym for you..LETP.

Laser Eustachian tuboplasty. I first saw reference to this a few years ago. A means by which laser is used to widen the Eustachian tube. It's been trialled mostly in people with chronic recurrent middle ear infection with loads of liquid there as well. And results have been good. After a futuristic style zapping these people are problem free on the whole. So could it be used for divers who are chronically bad equalizers?

I think it could.