6 - Syncope Flashcards
Syncope definition?
Syncope or “fainting”
Is a symptom complex consisting of a brief loss of consciousness associated with an ability to maintain postural tone that
spontaneously resolves without medical intervention
Near syncope?
Same thing but you dont loose consciousness
Pathophys of fainting?
Inciting event causing drop in CO -> decreased O2
- 10 sec of complete disruption of blood flow
- or reduction of cerebral perfusion by 35-50%
Pathophys causes of syncope?
- UKN - 37%
- Vasovagal (reflex mediated) - 21%
- cardiac - 10%
- Orthostatic
- meds
- neurologic
Its just fainting, why do we care?
Each diagnosis classification carries with it progostic risk
- cardiac double risk of death
- neurologic, increased death by 50%
- UKN - death by 30%
(Compared to gen pop)
Death risk of vasovagal?
No increased death risk over “normals”
Most deadly type of syncope?
Cardiac
Common cardiac causes of syncope?
HCM PE Acute MI - if myocardial dyskinesia reduces CO Brady and tachy dysrhythmias -> transient hypoperfusion
Ho do dysrhythmia induced syncope’s present?
Sudden and without prodromal symptoms
What is the largest determination of how cardiac syncope presents?
The autonomic nervous system’s ability to compensate for decreased CO
Degree of underlying CVD
___ is a form of reflex-mediated or neurally mediated syncope, is associated with inappropriate vasodilation, bradycardia or both
Vasovagal syncope
Prodrome for vasovagal syncope?
- Lightheadedness
- w/ or w/out nausea,
- pallor
- sweating
- feeling of warmth
Slow progressive onset with associated prodrome suggests?
Vasovagal syncope
Common triggers for vasovagal syncope?
Aka neurally/reflux-mediated
Exposure to:
- sight/sound
- smell
- fear
- pain
- emotional distress
- instrumentation
Prolonged standing in heat
Situations
- coughing
- micturition
- defecation
- swallowing
Carotid sinus hypersensitivity, another reflex-mediated syncope is characterized by?
Bradycardia or hypotension
MC: abnormal vagal response -> brady and asytole >3 sec
Patient population for carotid sinus hypersensitivity
Older patients with recurrent syncope and negative cardiac evaluations
Why do postural changes effect syncope?
What is this called?
The bodies compensation methods cannot keep blood where it needs to be against gravity (volume loss, tone lass etc)
Orthostatic hypotension or postural hypotension
Psych and syncope?
Up to 40% of vasovagal
Up to 62% of unexplained
Are associated with psych problems
Neurologic syncope is?
A zebra, this condition is rare
What conditions must be met for syncope to be considered neurologic?
The pt will have neurologic deficits that are transient.
They must have NO persistent neuro deficits
What is a rare cause of brainstem ischemia caused by exercise?
Subclavian steal syndrome
What happens with subclavian steel syndrome?
Exercise of the ipsilateral arm causes blood to shunt or be “stolen” from the vertebrobasilar system to the subclavian artery supplying the arm muscles
PE for subclavian steal syndrome?
MC narrowing on L
Decreased pulse volume and diminished blood pressure in the affected arm.
Why are seizures and syncope often confused?
Brief tonic-clonic movements are often associated with syncope
- confusion (postictal)
- tongue biting
- incontinence
- epileptic aura
Subarachnoid hemorrhage and syncope?
Fall and head injury from syncope can be a cause of subarachnoid hemorrhage
Common med classes that cause syncope?
- ED meds
- Anti-hypertensives
- B-blocker
- cardiac glycosides (digoxin)
- anti-dysrhythmics
- anti-psychotics
- anti-depressants
- anti-Parkinson’s
- phenothiazines
- nitrates
- ETOH
- Cocaine
Goals of evaluation for syncope pts in the ED?
ID death risk pts
If diagnosis is made treat that
If no diagnosis
- risk stratification
- through PE
- EEG
- any other tests needed
Red flag symptoms for syncope?
Chest pain
Palpitations
HA
Abdominal pain
So the same shit as everything else
Sudden syncope event without warning and events associated with exertion raise suspicion for?
Cardia dysrhythmia
Structural cardiopulmonary lesion
More than 5 syncopal episodes in 1 year is most likely?
More likely
- Vasovagal syncope for psych
Less likely dysrhythmia
History questions?
Drugs Etoh Aggressive wt loss attempts Fam hx (prolong QT, SCD etc) Single car crashes (elderly) - dont get hung up on the trauma and miss the cause
Convulsive syncope?
Mild, brief, tonic-clonic activity (remember seizures are often misdiagnosed as syncope)
Urinary incontinence?
Dont care, not useful in distinction
What is the most important tool for diagnosis of syncope?
The history
- diagnostic tests have low diagnostic yields
ECG and syncope?
Rarely leads to diagnosis but its simple and non-invasive so get one
Lab test for syncope?
Based on hx
But some common ones
- heme stool test (orthostatic)
- CBC (orthostatic)
- Hcg
- look for acidosis
- b-type natiuretic peptide or pro-b type naturietic peptide levels are predictive for morbidity
Hyperventilation maneuver?
Open-mouthed, slow, deep breaths at rate of 20-30 breaths/min for 2-3 min
- may help reproduce psychiatric syncope or prodromes
Clinical yield for CT, EEG, or LP with syncope?
Low
Which syncope pts get admitted?
Admit:
Cardiac and neurologic
Send home:
Vasovagal, orthostatic, med induced
- just fix the problem
Decision making and risk management, consider admission in pts with?
- hx of CHF
- abnormal ECG
- hematocrit <30
- dypsnea
- SBP <90 in ED
- syncope while supine
- syncope during exercise
- syncope w/out prodrome
- palpitations prior to syncope
- age >60
So all the cardiac shit
Syncope flow chart?
Slide 35
What tx do all the cardiac syncope pts need?
External defibrillators
Considerations for elderly pts with syncope?
- increased risk for bad outcomes
- risk increases w age
- L ventricle is less compliant
- decreased vascular tone
- decreased adrenergic response
- increased pathophysiologic issues (HTN, atherosclerosis)
Big concerns for preggo syncope?
Ectopic pregnancy
PE
Not so worried about cardiac
Joker: How can you shoot women and children?!
Door Gunner: Easy! You just don’t lead ‘em so much! [laughs cunningly] Ain’t war Hell?! [laughs]
