SYNCOPE Flashcards
Pathophysiology
10 seconds of complete disruption of blood flow or nutrient delivery to both cerebral cortex or to the brainstem RAS
OR
Reduction of cerebral perfusion by 35 - 50%
Etiology / Epidemiology
REFLEX MEDIATED:
Vasovagal (21%)
Situational:
-cough
-micturition
-defecation
-swallow
-neuralgia
Carotid Sinus Syndrome
CARDIAC (10%):
-Structural cardiopulmonary
-Dysrhythmias
VOLUME:
-Orthostatic Hypotension (9%)
NEUROLOGIC:
-TIA
-sublclavian steal
MEDICATION
NO ETIOLOGY ESTABLISHED (40%)
DDx Cardiac-Related Syncope
Structural Disease
-valvular heart disease
-aortic stenosis
-mycardial ischemia / infarction
-massive pulmonary embolism
-hypertrophic cardiomyopathy
-aortic dissection
Dysrhythmias
-tachydysrhythmias
-bradydysrhythmias
-long or short QT syndromes
Clinical features of aortic stenosis
Elderly
Chest Pain
Dyspnea on exertion
Syncope
Clinical Features of dysrhythmias
Typically sudden and usually without prodromal symptoms
DDX of Neural / Reflex Mediated Syncope
Vasovagal
Situational
Carotid Sinus Syndrome
Pathophysiology of Neural / Reflex Mediated Syncope
Inappropriate Vagal stimulation -> bradycardia AND/OR vasodilation
Clinical Features of Vasovagal Syncope
Prodrome or lightheadedness, +/- nausea, pallor, and/or sweating and associated feeling of warmth
a/w
unexpected / unpleasant sight, sound or smell, fear, severe pain, emotional distress
Clinical Features of Situational Syncope
Prodrome or lightheadedness, +/- nausea, pallor, and/or sweating and associated feeling of warmth
a/w
coughing, micturition, defecation, swallowing
Clinical Features of carotid sinus hypersensitivity
Prodrome or lightheadedness, +/- nausea, pallor, and/or sweating and associated feeling of warmth
a/w
carotid manipulation, shaving, head turning
Clinical Features of Orthostatic Syncope
Syncope within 3 min assuming upright position
Risk Factors for Orthostatic Syncope
Elderly
Intravascular Volume depletion (diarrhea, vomiting, decreased PO intake)
Neurologic disorders: parkinsons, MS
a / b blocking Medications
Pathophysiology of Orthostatic Syncope
Pooling of intravascular volume in lower extremities followed by inadequate cerebral perfusion after assuming upright position due to inappropriate intravascular volume or impaired sympathetic response
Elements of the HPI
Events preceding the loss of consciousness:
patient position
environmental stimuli
strenous activity
arm exercise
aura
Duration of LOC
Tonic Clonic Activity
Foaming at mouth
Tongue trauma
Post ictal state
Witnesses
Red Flags: Associated Symptoms
Chest pain
Palpitations / Sudden Event without prodrome
Shortness of breath
Back Pain
headache
diplopia
vertigo
focal weakness
Risk Factors
Recent Illnesses / vomiting / diarrhea
Alcohol Ingestion
Dieting / weight loss
Previous episodes
PMHx: underlying structural heart disease, arrythmias
FHx: prolonged QT, dysrythmias, sudden cardiac death
Medications: beta blocker / alpha blockers / CCB / Nitrites / Diuretics / Erection medications
Elements of physical exam
BP in both arms
Orthostatic Blood Pressure
Cardiac Exam
Neurologic Exam WITH cerebellar signs
Tests
Electrolytes
Extended Electrolytes
Glucose
Creatinine
CBC
ECG
BHCG
+/- CT Head if Neurological Findings
Risk factors for admission or expidited follow up
Syncope while supine
Syncope during exercise
Syncope without prodromal symptoms
Palpitations preceding syncope
Age > 60 or 65
Disposition: Criteria for discharge
Vasovagal
Carotid hypersensitivity
Situational
Orthostatic
medication-related
Disposition: Criteria for admission
Cardiac or Neurologic Syncope
Clinical Decision Making Tool
San Francisco Syncopy Rule
