Vasovagal syncope is a condition characterised by loss of consciousness typically when there
isn't enough blood flow to your brain. So, when the brain doesn't get enough blood it
doesn't get enough oxygen and nutrients and the brain shuts down and we pass out, that
is vasovagal syncope. Now, the most common reasons for vasovagal syncope are that you
have a susceptibility and you add on to that triggers, and I often think about vasovagal
syncope like a person who is susceptible which are then confronted with ducts all lining
up in a row before you trigger the attack. Some of these factors that come up to line
in a row can be things like dehydration, feeling fatigued and tired, lack of sleep, standing
for prolonged periods, being in a hot crowded environment which is very stuffy, or in a
crowded restaurant where you've just had some alcohol or a large meal. These are all trigger
factors for vasovagal syncope. Now, there's a form of syncope called situational syncope
and oftentimes these are in particular medical conditions. So for example, when you're having
your blood taken or when you watch a movie that makes you queasy because of some surgery
that you see in the movie or some gory scene, you might start to feel light-headed and the
mechanism for the lightheadedness is typically when you have a situation that shocks the
brain into adopting a protective stance. Although it's not very protective. It drops your blood
pressure and your heart rate and causes you to lose consciousness. So that's what vasovagal
syncope is.
Now, the top tips to prevent syncope will be to understand what your triggers for syncope
are. Now, if you know that you always have a tendency to feel light-headed or fainting
when you're standing for a long time at a school assembly or in church or in a hot warm
environment, then you avoid that situation. If you faint whenever you have blood taken,
then once again avoid that situation for example by asking to lie down when you have your blood
taken. It makes it much less likely that you will faint. The standard conservative advice
or what we would say to all patients coming through our vasovagal syncope clinic would
be to hydrate more, would be potentially to have more salt but only do this on the doctor’s
advice, only if your blood pressure is low or low/normal. You should learn to exercise
your muscles in particular your lower limb muscles. So there is a manoeuvre called an
isometric counter-pressure exercise and I'm going to demonstrate this to you. Put both
hands together and pull apart, grit your teeth, clench your gluteal muscles which are essentially
the buttocks, tense your quadriceps in your calves. So all your lower leg muscles. And
doing this tensing exercise like this is called an isometric counter-pressure exercise, and
what this does is it squeezes blood which is starting to pull in all your lower limbs
and your hands, arms and it squeezes the blood and pushes it back into your heart and improves
your blood pressure. This can be a very effective manoeuvre when you start to feel the onset
of syncope. For example, if you're sitting on a train on a commute to work and you know
that you have a tendency to feel light-headed when you stand up, you can already start this
clenching exercises and whilst you're seated and continue to clench or tense your muscles
as you stand up to get out of the train when you reach your platform or station. This is
a very helpful exercise that you should learn. The other thing to really understand is that
if you know you're going to faint, then for goodness sake get yourself to a safe place.
The most important thing is to sit down on the floor. You can either sit down or lie
down which is even better and elevate your feet, and when you're down, try and stay down
until you feel well. One of the things we commonly see especially on public transport
is when a patient faints and is horizontal, which is effectively very helpful to return
the blood back into your heart because you're not fighting gravity anymore. A good Samaritan
comes by and lifts you right up again supporting you by your arms and your shoulders, and oftentimes
your blood drains away again. You look pale and then you have another vasovagal syncope
episode. So oftentimes getting down to the floor, elevating your feet, having some fluids,
and making sure you feel better before you stand up is also a very good strategy to prevent
ongoing vasovagal syncope.