L9 - Syncope Flashcards
What is pre-syncope?
Gradual onset of dizziness/light headedness where somebody almost blacks out. They have memory of the event and if they fell they were able to help themselves down
Can have pre-syncope which leads to syncope
What is syncope?
Complete loss of consciousness and fall (loss of postural tone) usually resutls in some type of injury
No memory of event (lost time)
Transient, self limited & unknown cause
Why is a syncope work up difficult?
Work up is usually negative for everything, because whatever caused the problem is no longer present
Lots of stuff looks like syncope
Thorough history & physical is necessary as there aren’t any easy lab tests for diagnosis
What happens when you determine the cause of syncope?
The diagnosis ceases to be syncope as syncope by definition must be of unknown origin
“Syncope” that isn’t self limited or transient would really be what?
Coma
Dizziness is another word for what? What are the 3 main types?
= Pre-syncope
Vertigo
Disequilibirum
Lightheadedness
What is vertigo?
Type of dizziness/pre-syncope
Sense that the room is spinning, nausea/vomiting, worse with head movement, vestibular origin
What is disequilibirum?
Type of dizziness/pre-syncope
Imbalance –> fall while walking. Dont feel like are going to pass out.
What is lightheadedness?
True pre-syncope
Suggests lack of perfusion to the brain
What is the pathophysiology of syncope?
Cerebral hypoperfusion for 3-5 seconds
Does not include other explainable events like stroke
What assumptions can be made about an episode of syncope with twitching? What can be ruled out if there is no twitching?
You can see mild twitching just due to hypoperfusion so can’t just focus on seizure. Severe twitching points towards seizure
If no twitching is present, seizure still a possibility cuz can have non-convulsive seizure
What is suspected for syncope with urinary/fecal incontinence?
Seizure
What is suspected for syncope with tongue/mouth lesions?
Seizure
Bite tongue
What are risk factors for seizures?
Tumor Mass Stroke Trauma Infection/fever Alcohol or drugs (mainly withdrawal) Electrolyte imbalance
What is suspected when an episode of syncope results in a person falling a sleep?
Narcolepsy
What is suspected if an episode of syncope ends with transient confusion (dazed)?
Seizure presents like this, but other more serious neurological conditions can’t be ruled out
Called post-ictal state
How can stroke/TIA cause syncope?
Rare, but if isolate problem just at reticular activating system (consciousness center)
Usually would have many more signs/symptoms pointing towards
How can TIA incorrectly be explained by a witness as being very similar to syncope?
Weakness –> fall
Aphasia makes patient look unconscious
How can a tumor cause syncope?
Mass in reticular activating system
How can arrhythmias cause syncope?
Ventricular fib or tach (abrupt, no prodrome)
Supraventricular fib or tach (palpatations, chest pain or dyspnea)
Bradycardia/AV block (pre-syncope, dyspnea, exertional)
How do MI, PE and Aortic dissection present as syncope?
These abrupt events rarely cause syncope because these generally all present with way more symptoms than just syncope
What is the correlation between ejection fraction and arrhythmia?
If EF t had an episode arrhythmia yet
What area of cranial circulation is related to syncope? Related to stroke/TIA?
Posterior (brainstem)
Anterior (cortex)
What test is used to diagnose syncope related to vascular occlusion?
CT or MR angiogram
Not Ultrasound which is used for stroke/TIA
How are carotid disease or bruits related to syncope?
They aren’t (anterior vs. posterior circulation)
How does subclavian steal cause syncope?
L/R Subclavian –> L/R vertebral art –> “common” basillar art
One of the subclavian arteries has severe stenosis. This side “steals” blood from the other side via retrograde flow from common carotid.
It usually isn’t a problem but when have exertion on side with stenosis (like using a hammer) –> steals more blood –> no enough to brain –> syncope
What is suspected for a case of syncope brought on by shaving, head turning or a tight collar?
Carotid Sinus Syncope
What is carotid sinus syncope?
Have baroreceptors that are hypersensitive to manual stimulation –> changes in BP & HR –> syncope
What is another name for neurocardiogenic syncope?
Vasovagal Syncope
What is the most common cause of syncope?
Vasovagal syncope
What is the pathophysiology of vasovagal syncope?
Increase in parasymp & decrease in symp –> decreased contractility/HR & increase vasodialtion (decreased BP) –> hypoperfusion
What is it called when a vasovagal event is brought on by coughing, gagging, vomiting or going to the bathroom?
Situational Syncope
Caused by vagal nerve stimulation
How do dehydration or blood loss cause syncope?
Hypovolemia
What is suggested by syncope right after standing up?
Orthostatic syncope
How is orthostatic syncope caused?
Blunted baroreceptor or cardiac response related to age or medication
Hypovolemia can cause orthostatic syncope, but not all orthostatic syncope involved hypovolemia
What is the test for orthostatic syncope? How do you interpret the results?
Have patient lie down (not sit) for at least 5 min & measure BP & pulse while they lay down–> measure BP & pulse right after they stand up
If BP & Pulse go down = vasovagal
If systolic goes down 20, diastolic goes down 10 or the pulse goes up 10 = orthostatic hypotension
If BP nl or decreased, pulse is increased to > 120 and have pre-syncope symptoms = Postural Orthostatic Tachycardia Syndrome
How to interpret tilt table results?
nl = systolic increases a bit & diastolic decreases a bit
Orthostatic = systolic increases a ton & diastolic decreases a ton
Vasovagal = both decrease a ton while tilted, but immediately return to normal when tilt back to starting position
POTS = Systolic increases and ton & diastolic decreases a ton, but don’t return to normal quickly after return to starting position
What is suggested by syncope after prolonged standing?
Vasovagal
What is suggested by syncope that lasts seconds?
Cardiac cause
What is suggested by syncope that lasts minutes?
Seizure or reflexive cause
What is suggested by syncope with postdromal symptoms (signs right after syncope episode)?
Vasovagal
What is suggested by syncope with immediate recovery?
Cardiac cause
What are red flags for syncope?
Cardiac related signs (palpatations, syncope or chest pain)
Focal neurological symptoms (headache, diploplia or ataxia)
Exertional onset
What is a holter monitor?
Sort of like mobile telemetry the patient wears (EKG)
If don’t see what caused the syncope while in the hospital send them home with this on
What is an EP (electrophysiology) Study?
Measure electrical conduction system of the heart with multiple catheters
Use this to induce arrhythmia if haven’t been able to see it while just monitoring
Once find problem, ablate the area
What type of syncope is the most deadly & requires the most thorough work up?
Cardiac –> admission and monitoring
What is HOCM?
Unexplained cardiac hypertrophy –> sudden cardiac death in young atheletes
What is the order of tests done is looking for arrhythmia?
Telemotry
If that don’t work use halter monitor
If that don’t work use EP study
What is learned by a post syncope EEG?
Not much, because would only have results if do EEG during the actual seizure
What imaging is best to look for small stroke?
MRI
How can a history of stroke cause syncope?
Old lesions become seizure foci
What should you do first after a patient has syncope in front of you?
Do quick set of vitals
What is syncope if the patient has memory of the event?
Pre-syncope
What type of dizziness involves falling without any feelings that they are going to black out?
Disequilibrium
What type of dizziness involves a sense that the room is spinning?
Vertigo
What type of dizziness is worse with head movement?
Vertigo
Anatomical origin of vertigo?
Vestibular system
Cause of lightheadedness?
Inadequate perfusion
What is a post-ictal state?
After seizure are dazed/confused
Patient is fine until they swing a hammer with one arm. Diagnosis?
Subclavian steal
What type of dizziness presents with a nstagmus?
Vertigo
What are systemic causes of syncope?
Hypoglycemic Hypoxemia Hypovolumetric Hyponatremia Infection Drugs
What cause of syncope can present with pro & post-dromal neurological symptoms?
Stroke/TIA
What does HOCM stand for?
Hypertrophic Obstructive Cardiomyopathy
What causes of syncope which obstruct ouflow?
HOCM
Mass
Effusion/temponade
Valvular problem
What type of syncope can present with vision (fuzzy, tunnel, bright or gray-out), nausea/vomiting, sweating or tinnitus prodromal symptoms?
= Heavy prodrome
–> Vasovagal
Prodromal symptoms mainly point to what?
Vasovagal
