Taylor-Syncope Flashcards
why I don’t passout when I stand up
my baroreceptor reflex acts instantly to make sure brain is still perfused; sympathetics fire
besides sympathetics, what other way can we ensure we don’t pass out when standing up
muscle compression that compresses veins and pushes venous return to heart
acute response to standing up maintains what
maintains arterial pressure
has transient corrections of BP (when there is a change in pressure or blood volume)
baroreceptor reflex
has sustained management of BP and blood volume
kidneys
4 main variables in the normal orthostatic response
- total blood volume
- drugs/alcohol
- temperature
- recent meal
ways that a patient can lose blood volume and make orthostatic response slow
dehydration
hemorrhage
laying down too long
drugs that can cause orthostatic response to be sluggish
diuretics, B blockers and vasodilators, SSRI’s
what makes orthostatic response sluggish in regards to temp.
heat–vasodilates blood vessels
main thing to check first if someone experiences syncope
make sure it is not cardiac related (order ecg and labs)
transient loss of consciousness (fainting) w/ spontaneous recovery (20 sec)
Syncope
most common cause of syncope
inadequate perfusion of brain
labs to order to see if syncope is due to a metabolic issue
glucose levels (hypoglycemia)
CBC (anemia)
blowing off too much CO2 and blood vessels constrict causing what
loss of consciousness
most important cause of syncope to recognize even though it is only 10% of all cases
cardiac
if you identified patient did not pass out due to cardiac pathology, then what do you check for
Dysautonomia
autonomic dysfunction due to essential failure or delay of sympathetic activation +/or response
Dysautonomia
2 main types of cardiac causes of syncope
Arrhythmia
Long QT syndrome
hypotension when standing; dizziness or fainting when standing
Orthostatic Intolerance
how to measure Orthostatic or Postural Hypotension
a decrease in systolic BP by 20 mmHg or a decrease in diastolic BP of 10 mmHg w/in 3 minutes of standing
4 main types of Dysautonomia
- Vasovagal syncope
- Carotid sinus hypersensitivity
- pure autonomic failure
- PoTS
common faint reflex (multiple triggers); 70-80% of syncope cases
Vasovagal syncope
enhanced baroreflex in response to neck pressure
Carotid sinus hypersensitivity
entire autonomic system and cardiovascular system damaged; due to brain neurodegenerative disease
Primary autonomic failure
sustained rapid heart rate when standing
PoTS (postural tachycardia syndrome)
characterized by rapid bradycardia and hypotension (withdrawal of sympathetic tone and increased vagal firing)
Vasovagal syncope
specific degeneration of autonomic functions; inability to maintain bp when standing
Pure Autonomic Failure (PAF)
increased HR within first 10 minutes of standing due to unstable BP and low cerebral perfusion
PoTS (postural tachycardia syndrome)
seen recently after someone who has had COVID
PoTS
how to assess for dysautonomia
Head Upright Tilt test (HUT)
HUT test
check HR and BP of patient on tilted table w/out involvement of m. contraction
after HUT test, both BP and HR fall
Vasovagal response
after HUT test, only BP falls
Pure autonomic failure
after HUT test, HR increases and remains elevated; BP unstable
PoTS
top, middle, bottom represent what
top-normal
middle-PAF
bottom- PoTS
to treat and manage syncope
ecg and labs and FH
non-pharmacologic ways to treat syncope
- avoid triggers
- hydrate
- exercise (volume expansion)
pharmacologic ways to treat syncope:
basically drugs that will increase sympathetics
a1 receptor agonist used to treat syncope
Midodrine
drug that increases Na+ and fluid retention (volume expansion) used to treat syncope
Fludrocortisone
anticholinergic drugs that oppose parasympathetic effects and used to treat syncope
Atropine
Disopyramide
drugs that act like accessory catecholamines to treat syncope
Ephedrine/Pseuodophedrine
reduces serotonin reuptake drug used to treat syncope
SSRI’s
drug that will keep NE and Epi in synapse longer; used to treat syncope
Ritalin
a way to assess autonomic response and assess valve issues in heart
Valsalva maneuver
triggered by immersing face in water (CN V)
dive reflex
Involves parasympathetic mediated bradycardia; w/ sympathetic vasoconstriction in vasculature
dive reflex
2 ways to quickly lower HR on your own
splash your face with water
rub one carotid
