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Blackouts and Funny do’s Condition

Presentation

Notes Episodes with collapse

Before

Tonic-clonic seizure

* Any time, any position * Aura - smell, taste, strange feeling (a few seconds) * Goes blank or lip smacking before losing consciousness During * Goes stiff and lets out a grunt * Arms and legs go stiff for a period and the jaw is clenched tight — followed by jerking of the limbs (2-3 mins) * + tongue biting & pass urine After * Deep sleep after * On coming round, the patient is muddled Before * Fall in BP leading to cerebral hypo perfusion * Preceded by a feeling of lightheadedness, dimming of vision, a sweaty feeling, and a feeling of becoming distant (some get no

Syncope

warning - can be brief, but usually lasts minutes) * Pale and sweaty and slumps to ground, sometimes falling more stiffly During * Lies still (or sometimes small twitching movements) * Unconsciousness usually brief ( 40 years old For a period of 2 - 6 hours Almost total failure to acquire new information Patient appears confused - they characteristically ask the same question again and again, ignoring any answers * Otherwise, they can do quite complicated things such as driving

* * * *

Associated with migraines, but not epilepsy or cerebrovascular disease

* Focal neurological symptoms * Gradual onset over about 15-30 minutes * Usually visual symptoms (though numbness, tingling or speech disturbance can occur) * The typical headache usually follows, but may not (think of Ddx) Investigations * ECG (excluded rare arrhythmias like long QT syndrome) * Syncopal attack: fasting glucose, 24h ECG, echocardiogram, tilt table test * Seizure: MRI or CT brain scan, EEG, 24h EEG, calcium

Management * Driving regulations * Lifestyle: avoid any situation that could put them or anyone else at risk (swimming, shower instead of taking a bath)

Examination - to exclude * Pulse irregularity * Evidence of cardiac failure * Murmurs * Extra cranial bruits * Erect and supine blood pressures * Any focal neurological signs

Giddiness Condition

Presentation

Notes History

Key features * Timing: Intermittent or sustained? Duration? * Head movements: Signifies a peripheral lesion - BPPV * Auditory dysfunction: Deafness or tinnitus? - disturbance of the labyrinth or vestibulocochlear nerve. Once in the brain stem, auditory and vestibular function are separate

* Medication: Anticonvulsant toxicity causes vertigo. Aminoglycosides cause irreversible vestibular damage. * Eye movements: Nystagmus without vertigo generally points to a CNS cause * Signs of CNS involvement: Ataxia, dysarthria, sensory or motor signs in the limbs - points to an intracranial cause

Intermittent vertigo

Positional

Non-positional

Benign Paroxysmal Positional Vertigo (BPPV) * May follow a viral infection or head trauma * Often a period of a few days when patients are bed bound, because rising triggers disabling attacks of vertigo and vomiting

Treatment of BPPV * Positioning manoeuvres (e.g. Epley manoeuvre, Brandt-Daroff exercises) - remove debris within semicircular canals

* Brief attacks (60s) of vertigo each time their head is in a particular position (usually lying down) * Usually settles over a period of weeks * Diagnositc: Hallpike’s test

Other causes of positional vertigo: * Alcohol and anticonvulsant intoxication * Perilymph fistula (often post-traumatic and usually with a hearing deficit) * Central oculomotor disorders with failure of vestibulo-ocular reflexes

Meniere’s disease

Treatment for Meniere’s is symptomatic only as it is an episodic condition. Acetazolamide can be used as prophylaxis. Refer to ENT.

* Most common cause of intermittent peripheral, non-positional vertigo (but is overdiagnosed) * Middle-aged patients; episodes lasting hours * Assoc. tinnitus and a hearing deficit * During the episode, there is spontaneous nystagmus and between episodes there is a decline in hearing Other peripheral causes: Otosclerosis, hyperviscosity syndromes, syphilitic labyrinthitis, Cogan’s syndrome (autoimmune)

Other CNS causes: * Brain stem dysfunction symptoms: diploplia, ataxia, cranial nerve or limb deficits * Vertebrobasilar migraine (VBM) - mainly in children, episodeoes lasting minutes to hours with headache + (visual) aura * Multiple sclerosis - adults (lasting hours to weeks) * Vertebrobasilar ischamiea (VBI) - older adults, common cause of brief episodes + other transient neurological symptoms

Condition

Rarer causes

Presentation

Notes

* Vestibular epilepsy of the temporal lobes (there may be other epileptic features such as oroalimentary automatisms, or convulsions) Sustained vertigo Other acute vestibular lesions painting this picture (canal paresis): * trauma * infarction (hyperviscosity syndromes) * tumours (esp. acoustic nerve tumours, Schwannomas) * infections (esp. syphilis, TB, Lyme disease, Herpes zoster - causes acute vertigo, unilateral hearing loss, ipsilateral facial paresis, severe pain, malaise and characteristic herpetic vesicles around the external auditory meatus: ‘Ramsay Hunt syndrome’ Mx: aciclovir)

Idiopathic vestibular neuritis

Peripheral cause

Central causes

* Acute onset of vertigo, which persists for several weeks and then gradually subsides * Gaze-evoked nystagmus, with a rotatory component * Canal paresis on caloric testing * Believed to be due to infection * Mx - symptomatic (this resolves spontaneously) Brainstem lesions - look for other associated brainstem signs * Multiple sclerosis * Infarction * Tumours

Others Phobic vertigo * More vague sensation of unsteadiness that often fluctuates rather than being continuous * May be assoc. hyperventilation (difficulty catching the breath and Phobic vertigo

paraesthesia) - symptoms may be reproducible on hyperventilation * Sometimes due to failure of compensation following previous vestibular disturbance or may be a primary psychogenic disturbance

Management of phobic postural vertigo * Detailed explanation of the presumed basis of the syndrome, a misinterpretation of mismatched vestibular syndrome * This may be a form of cognitive therapy resulting from a reattribution of the causation of the dizziness

Condition

Presentation Investigations 1. Caloric testing * Water is introduced into one external auditory canal at 32 and 41 deg. Celcius. This normally causes nystagmus with specific latency and duration that can be measured * Cold causes the fast phase of the nystagmus to the Opposite side and Warm to the Same side (COWS) 2. Auditory evoked potentials * Measures delay in central auditory pathyways, esp. in MS 3. Audiometry * Tests of hearing threshold provide evidence of function of the auditory component of the 8th cranial nerve 4. MRI scan * Investigation of choice in central vestibular disturbance * CT brain may miss posterior fossa lesions, esp. small acoustic Schwannomas, and will miss demyelination

Vertigo * Causes nausea and sometimes vomiting * There may be associated fear, sweating and pallor * Vertigo is due to a mismatch between sensory inputs involved in maintaining posture - visual, proprioceptive and vestibular systems * In practice, vertigo is usually due to dysfunction of peripheral vestibular apparatus or its central pathways * 70% of vertigo is caused by four syndromes: 1. Benign paroxysmal positioning vertigo (BPPV) 2. Vestibular neuritis 3. Meniere’s disease 4. Phobic vertigo

Notes

Management Symptomatic * Antihistamines e.g. betahistine and cinnarizine - these are sedative and patients should not operate machinery or drink alcohol * Dopaminergic antagonists e.g. prochlorperazine and metaclopramide - mildly sedative but think of extrapyramidal side effects long term (>6 months) * Anticholinergics e.g. hyoscine - can cause dry mouth, constipation and sometimes urinary retention or confusion...