Don't read this if you're having your breakfast, even though you may discover something useful about a 17th century Italian who had a way with equalising. Raymond Gallacher is the man with the bloody nose and the inquisitive nature
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Which manoeuvre works for you?
MOST OF MY MENTAL RAMBLINGS BEGIN AT THE WATER'S EDGE. This is when I feel the most need to divert my thoughts.
I was diving with my friend and mentor Jim Gibbon, and he had filled my head with warnings about the currents. There always appears to be something worth worrying about in the water off Argyll.
As a result of worrying about being swept away to Ireland, I had been clearing badly, and I noticed that I had a little blood in my mask. While at 20m, I had felt my nasal passages fill up, and that is not usually a good thing.
When I finally ambled sideways up the shingle, I blew my nose and produced some big lumps of soft tissue. It may have been brain tissue - I didn't investigate.
A core skill in diving is learning to equalise the pressure inside your air-filled spaces with the changes in pressure outside. I admit that I often clear badly. Nose-bleeding is not unknown in divers, and is a result of coping poorly with pressure changes.
The technique that you probably use is to grab your nose and blow gently. If you read the manuals, you'll know that this is called the Valsalva manoeuvre.
Unfortunately I get very little out of this manoeuvre, and instead have to go through a variety of underwater contortions to feel comfortable, but most people have no problem with this little trick, passed on to us from the early anatomists.
"Valsalva," you say, "early anatomist - I knew that." I shall return to Mr Valsalva.
The early anatomists were not doing any of this work for your benefit. It's hard to imagine what they thought they were up to, but they spent a lot of time eviscerating small mammals and, given the chance, people.
Holding your nose while blowing through it - wonder who first thought of that? |
They wanted to see how all the organs and tissues worked and, rather like a small child with a doll, the obvious thing to do was to pull the subject apart. Early anatomy consisted of taking all the stuff inside-out. Just like taking an engine apart, the body never worked again, and none of the stuff fitted back in anyway.
Greek anatomists discovered this while removing bits and bobs from Trojan and Persian prisoners of war. The PoWs gave good service in this until the squirming stopped. Yes, they wanted to see the bits actually work before they took them out.
And so to Antonio Valsalva, born in Imola in Italy in 1666. He grew up being just too damned smart all round. He was educated by the Jesuits, which aroused his interest in human anatomy. I think it might have been the Inquisition that aroused Jesuits' interest in anatomy, butI have few details.
He studied mathematics, philosophy, Greek and Latin and was good at all of it. Not only was he a well-thought-of Renaissance man, but he discovered an enormous amount of biological stuff.
His big show came in 1704, when he published his discoveries on the structure of the ear. He subdivided it into internal, middle and external parts. We still use this classification today when learning the components of the aural system.
Valsalva also demonstrated a method of inflating the middle ear. This is his manoeuvre, and it is still used, not only by divers but for other clinical reasons. It has medical value in controlling the heart rate and the emptying of the bladder.
You may think Antonio was something of an improvement on the bloodsoaked entrail-haulers of classical times, but he too carried on a number of their creepy and dysfunctional habits. Do not eat at this point in your reading.
Valsalva used to lick the stuff that poured out of the bodies. That's right, he actually made a study of gangrene by that very method. He once had his tongue made non-operational for a whole day after tasting the serum from gangrene.
He was trying to classify these liquids by the chemistry of the day - which meant putting your mouth on them. He wrote a lot about these juices, particularly gangrene. It just goes to show that you can get used to the taste of anything.
You may not be surprised to know that Valsalva also had a great interest in insanity, and was all for the humane treatment of the insane. Perhaps he saw this as a kind of insurance policy.
Sadly, his lust for discovery damaged his health, and he died in Bologna in 1723. There is no evidence that this might have been connected with fooling around with leaking, diseased corpses.
If you, like me, have difficulty getting any relief from the Valsalva manoeuvre, or simply find its author too disturbing to contemplate, there are other techniques you can try.
There is the Toynbee manoeuvre, in which you hold your nose and then swallow. It isn't bad, but it's hard to do when your mouth is dry.
The Edmonds technique is all about movement. You wiggle your jaw from side to side, and then stick your jaw forward. It's a toffee-chewing kind of action that I find hard to manage.
Lastly, there is the Lowry technique, in which you swallow and blow at the same time. I have no intention of experimenting with this one under water.
The safest advice is to clear before discomfort begins, regularly and gently. Abort the dive if you cannot clear, and are in discomfort or pain. Forcing through the pain barrier is a bad idea. If your body is giving you a safety message - listen.
If you have had a cold, your ability to clear your ears will be impaired. The Navy's advice is that you never dive after an infection until at least 10 days after the last symptoms disappear. You are risking perforations of the eardrum if you can't equalise that pressure.
Make friends with your doctor and take his advice. Finally, never stick your tongue into stuff you don't understand.
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