Blackouts and Collapse Flashcards
What is a blackout?
Loss of consciousness.
Patient usually lie still but jerking and twitching movements can occur. They are sometimes mistaken for a convulsion.
Their appearance is pale.
Incontinence of urine or faeces can occur.
The recovery is usually rapid followed by a general fatigue as opposed to post-ictal drowsiness and confusion following a seizure.
How to take a good blackout history.
Did the patient lose awareness?
Did the patient injury themselves?
Does the patient move? Are they stiff or floppy?
Is there any incontinence?
Does their complexion change?
Does the patient bite the side of their tongue?
Are there associated symptoms like palpitations, sweats, pallor, chest pain and dyspnoea?
How long does the attack last?
Any prodromal symptoms?
How much does the patient remember about the attack? Muscle aches after?
Confused or sleepy after?
When did the blackouts start?
More than one?
Increasing in frequence?
Family history
General causes of blackout.
Vasovagal syncope
Situation syncope
Carotid sinus syncope
Epilepsy
Stokes-Adams attacks
Hypoglycaemia
Postural hypotension
Anxiety
Drop attacks
Factitious blackouts
Explain vasovagal syncope.
Due to reflex bradycardia +/- peripheral vasodilation provoked by emotion, pain, or standing for too long.
Explain a vasovagal episode.
The onset is over seconds and is often preceded by pre-syncopal symptoms like nausea, pallor, sweating and narrowing of visual fields.
Brief clonic jerking of the limbs may occur.
No tonic/clonic sequence.
Urinary incontinence is uncommon, and no tongue biting.
Unconsciousness usually lasts for 2 min and recovery is rapid.
Explain situation syncope.
Symptoms are similar to vasovagal syncope but there is a clear precipitant.
Such as;
Cough syncope
Effort syncope
Micturition syncope
etc…
Explain carotid sinus syncope.
Hypersensitive baroreceptors cause excessive reflex bradycardia +/- vasodilation on minimal stimulation like head turning, shaving or wearing a tight collar.
Explain Stokes-Adams attacks.
Transient arrhythmias causing decrease in CO and LOC.
The patient falls to the ground often without no warning, and is pale with a slow or absent pulse.
The recovery is in seconds, the patient flushes, the pulse speeds up and consciousness is regained.
Attacks may happen several times a day and in any posture.
What are drop-attacks?
Sudden fall to the ground without LOC.
They are mostly benign and due to leg weakness but may also be caused by hydrocpehalus, cataplexy or narcolepsy.
What are factitious blackouts?
Pseudoseizures
Münchausen’s
Examinations of blackouts.
CVS
Neurological
Measure BP lying and standing
Investigations of blackouts.
All with recurrent syncope or falls need cardiac assessment.
ECG
Bloods - FBC, U&Es, Mg2+, Ca2+, glucose, K+
Tilt-table test
EEG
Sleep EEG
Echocardiogram
CT/MRI
ABG if practical and indicated
