Blackouts Flashcards
Describe vasovagal (neurocardiogenic) syncope
Occurs due to reflex bradycardia and peripheral vasodilation provoked by emotion, pain or standing too long
Onset is over seconds
Often preceded by pre-syncopal symptoms eg. nausea, pallor, sweating and narrowing of the visual fields
Brief clonic jerking of the limbs may occur due to cerebral hypoperfusion but there is no tonic/clonic sequence
Urinary incontinence is uncommon and there is no tongue biting
Recovery is fast - unconsciousness only lasts 2 mins
Name 3 types of situation syncope
Cough syncope - occurs after a paroxysm of coughing
Effort syncope - bought on by exercise, usually a cardiac cause such as aortic stenosis or HCM
Micturition syncope - happens after or during urination mostly to men at night
Describe carotid sinus syncope
Hypersensitive baroreceptors cause excessive bradycardia +/- vasodilation on minimal stimulation - head turning and shaving
Describe epilepsy
Attacks when asleep or lying down Aura Identifiable triggers Altered breathing Cyanosis (pale) Typical tonic clonic movements (stiff before jerking movement) Incontinence of urine Tongue biting (side of the tongue) Prolonged post ictal state Confusion Drowsiness Amnesia Transient focal paralysis (Todds palsy)
Describe stokes Adams attacks
Transient arrhythmias cause decreased cardiac output and loss of consciousness
The patient falls to the ground (often with no warning and injuries are common) and is pale with a slow or absent pulse
Recovery is in seconds, the patient flushes, the pulse speeds up and consciousness is regained
Anoxic clonic jerks may occur if prolonged LOC
Attacks may happen several times a day and in any posture
Describe the presentation of a blackout caused by hypoglycaemia
Tremor
Hunger
Perspiration herald light headedness or LOC
Rare in non-diabetics
Describe orthostatic hypotension
Unsteadiness or LOC on standing from lying in those with inadequate vasomotor reflexes
List some causes orthostatic hypotension
Autonomic neuropathy
Antihypertensive medication
Over diuresis
Multisystem atrophy
Describe the presentation of a blackout due to anxiety
Hyperventilation Tremor Sweating Tachycardia Parasthesiae Light headedness No LOC
Describe drop attacks
No LOC
Sudden fall to the ground
What causes drop attacks
Benign
Leg weakness
May be sue to hydrocephalus, cataplexy (loss of muscle tone in response to emotions) or narcolepsy (suddenly falling asleep throughout the day)
What 2 conditions present with factitious blackouts?
Pseudo seizures
Munchausen’s
What investigations would you do for someone presenting with a blackout
Cardiovascular and neurological examination Measure BP lying and standing ECG +/- 24hr ECG Echocardiogram CT/MRI brain ABG if practical
What should be advised in regard to driving when someone is being investigated for blackouts?
Advise against driving
