Dr Peter Wilmshurst has been a qualified doctor for over 25 years. He has served on the BSAC Medical Committee since 1977 and also advises the HSE on diving.
WHAT'S AGE GOT TO DO WITH IT?
I am 58 and regularly dive in cold Finnish waters. What health factors should a fit and healthy older diver take into account compared with younger divers? How does ageing affect one's fitness to dive? And how can one best prolong a diving career?
Generally, as people get older they tend to become less fit, fatter and prone to degenerative diseases.
A decreased level of fitness at any age means that a diver should avoid strenuously demanding conditions.
There is a line of thought that older, fatter individuals are at a greater risk of decompression sickness because of increased bubble formation after dives. However, this view originated from observations made on caisson workers (commercial divers), whose exposure to high levels of nitrogen is very different to that of amateur divers.
It is a fact that the prevalence and size of patent foramen ovale (PFO or hole in the heart) decreases with age, which should mean that older divers have less risk of decompression sickness as a result of that condition.
In short, there is no conclusive evidence that older divers are at increased risk of decompression sickness.
However, there is evidence that older divers who smoke are at increased risk of pulmonary barotrauma. Smoking causes changes in the lungs which lead to gas getting trapped, which increases the chances of a burst lung. The longer you have smoked, the greater the changes in lung function and the greater risk you run.
The main danger that an elderly diver faces compared with his younger counterparts is the risk of sudden incapacity in the water.
Heart attacks, acute heart failure and strokes occur suddenly. If they do so under water, they are likely to prove fatal for the diver, and his buddy could get injured or die attempting a rescue.
Older divers can minimise all risks by keeping themselves as fit as possible, eating a sensible diet and not smoking.
The advantage of being an older diver is the experience behind you - the ability to realise your limitations and to dive accordingly.
Is it possible to suffer serious ear barotrauma without having had problems during a dive? As I surfaced from a correctly profiled 33m-dive I realised that my left ear had tinnitus, partial deafness and a "full" sensation. During the dive I had had no ear-clearing problems. It has been six months now and I still have the same symptoms. An additional point is that I am blind. Luca
Serious ear barotrauma can occur without the diver experiencing pain in the ear during the dive, nor having any difficulty with ear clearing. It sounds very much as if that is what happened here. A rupture of the round or oval window can produce permanent tinnitus and impaired hearing. When this has happened once there is an increased possibility of it happening again in the same ear, and possibly in the other ear too. To have tinnitus and deafness in both ears is quite disabling.
I advise anyone who has such symptoms in one ear to think very carefully about the consequences of suffering the same symptoms in both ears before resuming diving. For someone who is blind it is even more disabling. I would strongly recommend that you stop diving.
A deafening no
I am due to have a stapedectomy on my right ear to correct increasing deafness. My doctor, who is not a diving medical specialist, recommends that I never dive again. Is this really necessary? Would diving permanently damage the ear or is it just a case of the operation having to be repeated? Are there safe limits? Penny
The stapes is a tiny bone in the middle ear which transmits sound waves from the eardrum to the inner ear. If the stapes becomes diseased and thickened and unable to transmit sound, it causes deafness. The stapes can be removed and replaced by a tiny prosthesis. The operation is called a stapedectomy.
The middle ear has to be opened and its structures are never normal afterwards. As a result there is an increased risk of middle-ear barotrauma when the ears are exposed to large pressure changes. The stapes prosthesis could be driven inwards, destroying the hearing entirely.
Even shallow scuba diving produces sufficient pressure changes to endanger hearing after a stapedectomy.
I went diving in Costa Rica. I did two dives per day, each between 18m and 27m. On the fifth day, 10 minutes after the first dive, I got cramp in my mid-back and during the next 10 minutes both my legs started to tingle. I was given oxygen and the symptoms entirely disappeared over the next hour. I was not recompressed. Was this a bend? When can I dive again? Martin
This sounds like a spinal bend and you are very lucky to have completely recovered. Oxygen undoubtedly helps in this situation but recompression is required.
Before diving again you must see a diving medical specialist to determine why you had the bend. Possible causes include a cardiac shunt, lung disease causing barotrauma and arterial gas embolism, or a rigorous series of dives.
What are skin bends? Phillip
Skin bends are a form of decompression sickness. They affect a diver's torso more frequently than limbs. The diver usually becomes aware of skin bends because of an itching. Sometimes, however, there is no itching but a rash is noticed when the diver gets changed. So in many cases it is difficult to be sure when the bend first started.
With amateur divers the rash is usually noticed between 30 minutes and 2 hours after surfacing. It often starts as an even pink rash which becomes a mottled pink and purple. It can be improved by oxygen and recompression. Untreated, it goes in a day or two.
The rash does no harm in itself, but it is important to seek help for two reasons.
Firstly, it can be associated with otherwise unnoticed neurological decompression sickness, which would be picked up in a doctor's examination and requires treatment.
Secondly, skin bends are associated with a high probability of the affected diver having had a cardiac shunt (often a PFO). Divers who have had a skin bend should have tests to see whether they have had a cardiac shunt.
If they have, there is a greatly increased risk of neurological decompression sickness on future dives, even ones well inside the tables.
Facing the symptoms
After a dive to only 7m, during which I had pain in my right ear, I found that the right side of my face was paralysed. I was put onto oxygen and was recompressed in a chamber. The weakness recovered under recompression. I was told it was caused by a bubble but was not a bend. What was it? Tony
This is a rare condition called facial nerve baroparesis and it is often mistaken for decompression sickness. The usual causes of paralysis after a dive are the bends or arterial gas embolism. In both these cases bubbles block blood vessels supplying blood to the brain or spinal cord. This damages or kills nerves in those areas. If the area of the brain affected controls movement of an arm, for example, that arm will be paralysed.
One can get an effect like a stroke, with weakness affecting the arm, leg and face on one side of the body while the other side has normal power.
There are many other effects besides weakness. Sometimes power is normal but balance is affected or there is tingling due to the involvement of sensory nerve supply.
Weakness can be very localised. If only the small area of the brain which controls the face is damaged, the only effect is that one side of the face droops.
However, another reason for paralysis of one side of the face could be related to the facial nerve fibres which control facial movement. The facial nerve passes through the middle ear and through a bony canal. Pressure on a nerve can cause it to be temporarily paralysed. So pressure on the facial nerve causes the whole of that side of the face to droop.
Occasionally divers fail to equalise pressure in an ear when diving. It's not enough to cause the eardrum to burst, but it is enough to exert pressure on the delicate facial nerve in its canal and cause it to be paralysed.
The treatment of this condition is the same as for decompression illness. Oxygen should be given to re-absorb nitrogen from the middle ear and reduce pressure on the nerve, and the casualty should be taken to a recompression chamber.
The weakness of the nerve often recovers immediately following treatment, but sometimes recovery is delayed or incomplete. It is important to remember that this condition can occur without there having been any pain in the ear or difficulty in ear clearing during the dive.
The casualty should always be taken to a recompression chamber.
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