00:01
So how do we evaluate these patients
who present with syncope?
Well first is we need to check
blood pressure and heart rate.
00:07
Both lying, sitting, and standing.
00:09
Orthostatic blood pressures
are performed
in the line sitting,
and standing position.
00:14
And this helps us to interrogate
potential problems
with postural syncope
or orthostasis.
00:21
And that's done through orthostatic
blood pressure and heart rate.
00:23
Typically, we checked blood pressure
and heart rate lying
after five minutes sitting
and after five minutes standing,
and we're looking for a drop of
20 mmHg in the systolic pressure,
10 mmHg
in the diastolic pressure
without compensatory tachycardia,
without an increase in heart rate
by 10 beats per minute.
00:43
We can also do tilt-table testing.
00:45
This is more provocative
postural testing,
where we look at blood pressure, and
heart rate, and cardiac rate
at a range of lying positions,
the table tilts.
00:56
and we can induce
that postural activation
that can drive some patients
to syncope.
01:02
So this is a
good provocative test
for postural orthostatic
mediated syncope.
01:07
And the neuropathy testing can
be performed in some patients.
01:10
Autonomic neuropathy is a rare cause
of neurally mediated syncope
and neuropathic testing.
01:16
And autonomic nerve testing
can be helpful in those patients.
01:21
What about the treatment?
How do we treat these patients?
Well, what we said
was going on
is either a problem
with venodilation,
vasodilation of
vasodepressor mediated process,
or bradycardia.
01:32
And that's a vaguely
mediated process.
01:34
And so when we think about syncope,
there's vasovagal syncope,
which may be driven by problems
with too little blood pressure
and vagovagal syncope,
which may be mediated by
a reduction in heart rate.
01:47
And the final result is
cerebral hypoperfusion.
01:49
But when we treat patients,
we're looking to address
the vaso problem
and the vagal problem.
01:56
So our treatments can be divided
into both of those two categories.
01:59
Our goal is to
increase blood pressure
and increase heart rate.
02:04
There are several things
that should be avoided.
02:06
When we think about blood pressure,
we want to avoid medications
that reduce blood pressure
like anticholinergics
and antihypertensives.
02:13
When we think about
increasing heart rate,
we want to avoid medications
that reduce heart rate
like beta blockers.
02:20
At the same time,
there are things we can prescribe
to promote increase
in blood pressure
and increase in heart rate.
02:25
Hydration is the
most important thing
that can be done
for these patients
in addition to
compression stockings
to increase venous return
to the heart.
02:33
Midodrin is an agent that stimulates
increase in blood pressure.
02:36
Fludrocortisone is a medication
that increases
water reabsorption
in the kidneys,
and it can increase
blood pressure.
02:43
And both of those medications
can be important
with the need to increase heart rate
for vagovagal interventions.
02:51
And then we also think about
lifestyle adjustments and
lifestyle interventions
to help treat these patients.
02:57
We talk to patients and counsel them
on being slow to rise,
when standing to be
located near something
where they can hold on
or not jumping right up,
and walking,
and waiting time for their
parasympathetic and
sympathetic tone to balance.
03:11
Compression stockings
can also be helpful
for increasing venous return
to the heart.
03:17
And for managing heart rate,
management involves interventions
to avoid situations
that may induce syncope.
03:24
And this can be important
for situational syncope,
we avoid situations
that may drive a reduction
in parasympathetic
and sympathetic balance.