The Dizzy Patient Flashcards
which systems does the balance system rely on inputs from
inner ear
eyes
joints
heart brain
which cardiac problems can cause dizziness
arrhythmias and postural hypotension
how can DM cause dizziness
hypoglycaemia
how can arthritis cause dizziness
in the neck can occlude the vertebral arteries, resulting in dizziness
nystagmus
Eyes make repetitive, uncontrolled movements
These often result in reduced vision and depth perception and can affect balance and coordination.
vestibular nystagmus
VOR: activation of the vestibular system causes eye movement
This reflex functions to stabilise images on the retinas during head movement by producing eye movements in the opposite direction to head movement
impairement can cause vestibular nystagmus
Note: VOR is important for stabilising vision all the time, it may be hard to read small print
what are important things to elicit from the history of a dizzy patient
- Triggers – movement, standing up
- Time course
- Associated symptoms
- Precipitators
- Alleviating factors
- Medication
examination of a dizzy patient
- Otoscopy
- Neurological
- BP - lying and standing
- Balance system
- Audiometry
what can cause postural dizziness
low Sodium, low blood pressure, anaemia (check Hb)
can stress cause dizziness
yes, also through hyperventilation
benign positional paroxysmal vertigo
very common
attacks of sudden rotational vertigo lasting >30 seconds that are provoked by head turning
symptoms of BPPV
usually just vertigo
rare to have other ontological symptoms eg hearing loss, aural fullness or tinnitus
aetiology of BPPV
- Common after head injury
- Ear surgery
- Idiopathic
- Middle ear disease
- Otosclerosis
pathogenesis of BPPV
displacement of otoconias in urticle into semicircular canals
why is BPPV the most common cause of vertigo looking up
otoconia are most commonly displaced into posterior SCC, this causes vertigo on looking up
what may BPPV be confused with
vertebrobasilar insufficiency - poor blood supply in basilar and vertebral arteries due to atherosclerosis
how would BPPV be differentiated from vertebrobasilar insufficiency
diagnosis of vertebrobasilar insufficiency requires symptoms of impaired circulation in the posterior brain due in association with vertigo
eg bilateral visual disturbance, weakness and numbness, nausea and vomiting, slurred speech, loss of coordination etc.
when is vertigo particularly experienced in BPPV
- Looking up
- Turning in bed, often worse on one side
- First lying down in bed at night
- On first getting out of bed in the morning
- Bending forward
- Rising from bending
- Moving head quickly, often only in one direction
what negatives are important to establish in the diagnosis of BPPV
- No persistent vertigo
- No speech, visual, motor or sensory problems
- No tinnitus, headache, facial numbness or dysphagia
- No vertical nystagmus
what test is used in the diagnosis of BPPV
Hallpike’s test: this rotates the posterior semicircular canal in the plane of gravity
The patient’s eyes must be open and they must look straight ahead. While supine, the head is held and turned 40 degrees to one side, then rapidly lowered to below couch level. Ask the patient if they feel dizzy and look for nystagmus.
This lasts for under a minute due to adaption and reoccurs on sitting. If any of these features are absent (or persisting nystagmus), seek a central cause. The test fatigues so can only be performed accurately once.
name 2 important points about the Hallpike test
test fatigues - must be right first time
patient must not close eyes
Epley manoeuvre
BPPV diagnosis - allows displaced otoconia to be relocated back into the urticle using gravity
what exercise can be performed if patient cannot tolerate Epley or Hallpike
Brandt-Daroff Exercise
treatment of BPPV
it is usually self-limiting in months
alcohol intake may help
drugs: vestibular sedatives and histamine analogues
