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Vertigo
We have all experienced sometimes the feeling of dizziness,
giddiness, unsteadiness, lightheadedness, we understand that all
these symptoms means some kind of body balance disturbance. The
causes are diverse ranging from simple and well known causes to most
of us like low blood pressure, low blood glucose level, fever, sea
sickness, electrolyte imbalance, gastro- intestinal problems, or
(simply tired and did not sleep enough) to a diverse and serious
number of central and peripheral nervous system illnesses.
So What is Vertigo?
Vertigo is simply hallucination of movement leading to the feeling
that either the objects are moving in a certain direction around the
patient ( objective vertigo ) or the patient himself ( herself ) is
moving in a certain direction. It is always associated with
Nystagmus ( continuous involuntary oscillatory side to side movement
of the patient's eye pupils). I think most of us have never
experienced that feeling except sometimes if you visited your ENT (
ear, nose and throat) specialist for an ear wash. or unfortunate ear
drum perforation due to inability to equalize the pressure on your
ear drums while diving.
Disturbance in the vestibular pathway (semicircular canals in the
inner ear and their connections to the brain) lead to this feeling.
Causes of Vertigo in diving
1. Unequal stimulation of both inner ears (vestibular system)
a.This happens if external ear canal is obstructed (partially or
totally) by cerumen (wax), inflammation in the external ear canal (
swimming pool fungal or bacterial infections ) tight fitting hood,
preventing the flow of water freely in both ears.
b. Tympanic membrane (ear drum) perforation, due to unequal pressure
on both sides of ear drum in case of
middle ear barotrauma of descent.
middle ear barotraumas of ascent.
External ear barotrauma.
Shock wave.
2. Inner ear barotraumas
This happens as serious complication of middle ear barotraumas when
the membranes separating middle and inner ear also rupture (round
and oval windows) with damage and hemorrhage in the inner ear. ***
serious inner ear barotraumas can happen by forceful valsalva
maneuver ( pressure equalization on the ear drums during diving)
3. Decompression Sickness
Inner ear decompression sickness explanations are diverse, but the
definite outcome is pathology in the inner ear ( hemorrhage, edema(
tissue swelling and tissue fluid accumulation) caused by nitrogen or
helium bubbles ( in technical divers) formation in the inner ear
space. This space is limited by the surrounding bones, so the
manifestations of the pathology are rapid and dramatic.
Case Report
A 42 years experienced diver ( Air) in a vacation to the red sea ,
in the month of April , has been diving for 3 days every day 2
dives, the depths ranging from 25 meters 12 meters, dive times were
relatively long ( 60-70 minutes) due to his excellent air
consumption, on the fourth day and about 10 minutes after his first
dive ( 28 meters, 72 minutes), he experienced a sense of dizziness,
he started vomiting, the best position for him is laying down,
closing his eyes and with the slightest movement, he again feels
dizzy and vomits.
This diver was very experienced, but he thought that he might have
eaten something bad especially; he had some diarrhea from the day
before.
His wife as a nurse was not convinced especially when the boat
docked and her husband can not stand up or walk steadily, but still
he insisted he is OK.OK.
Any how, I saw this patient 4 hours later, when he started to think
may be there is something and under pressure from his wife.
He was dizzy? No he had vertigo. So a simple question? Do you feel
the surrounding moving around with your eyes opened or you are
moving yourself around? If the answer is YES, give him oxygen and
transfer to the nearest recompression chamber.
So this was a case of straight forward Inner ear decompression
sickness
During the chamber treatment and afterwards this diver kept
repeating the same question? Why me? I did not make any thing wrong
check my computer !
The answer is you are dehydrated by :
1. You are coming from home ( Europe ) in April already dehydrated .
How much do you drink ( Water ) at home in April ?
2. Repetitive long dives.
3. Travelers' diarrhea.
And also physiological variation as you are now 42 years old (of
course he did not like this one).
This is a scenario that can happen to any of us especially on diving
safaris.
To end the discussion about vertigo, there are other causes less
important to divers,
But for us the expression dizzy, giddy, lightheaded, not feeling ok
after any dive is not ok and should be well interpreted by the dive
guide and not mislead by the experienced diver.
Dr. Hanaa Nessim
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