Dizzy patient Flashcards
What is dizziness?
Non-specific term which can cover vertigo, pre-syncope, disequilibrium and others
What is vertigo?
Sensation of movement (usually spinning)
What are the end organs of the inner ear?
Saccule, urticle, three ampulla (cupula) of the semicircular canals
What is the structure of the inner ear called?
Labyrinth
Name the two parts of the labyrinth
Bony and membranous labyrinth
What type of movement do the semicircular canals sense?
Rotational
What type of movement do the urticle and saccule sense?
Linear acceleration
What are the components of the balance system?
Inner ear Eyes Joints (proprioception) Brain Heart
List the pathologies affecting the inner ear which may affect the balance system
BPPV
Menieres
Vestibular neuronitis
List the pathologies affecting the eye which may affect the balance system
Any pathology which causes visual loss (e.g diabetic retinopathy, cataracts)
Sight is important as horizontal and verticals will be used by the brain to correct balance. T/F
True buddy
List the pathologies affecting the joints which may affect the balance system
Diabetes neuropathy
Arthritis
Neurological conditions
List the pathologies affecting the heart which may affect the balance system
Arrhythmia
Postural hypotension
(heart causes pre-syncope not vertigo)
List the pathologies affecting the brain which may affect the balance system
Stress
Migraine
Space occupying lesion
Multiple sclerosis
Explain the vestibulo-ocular reflex
Horizontal movement of the head causes excitation at one side of the cupula and inhibition at the other side allowing fixed focus of the eyes despite movement (the image therefore remains in the centre of the visual fields thus stabilising vision)
(head moves to right -> right side of cupula excited ; left side of cupula inhibited)
What, apart from head movement, can stimulate the vestibulo-ocular reflex? This can be used to elicit clinical signs
Cold water/air
Why is the vestibulo-ocular reflex important clinically?
In vestibular, and some central, pathologies nystagmus will be observed (direction dependent on exact site of pathology)
What is important to test with regard to vestibular function?
Test for nystagmus
How common is dizziness?
Extremely common, particularly in the elderly
List possible causes of dizziness
CVS Haematological Metabolic Anxiety Trauma (fracture) Otological Neurological Drug side effects Migraine
Which medications are particularly implicated in dizziness?
Benzodiazapines
Anti-psychotics
Anti-depressants
Which examinations are important to perform on a patient with dizziness?
Otoscope Neurological Sitting and standing blood pressure Balance (Rombergs test) Audiometry
What is Rombergs test?
Standing patient is asked to close their eyes (positive if there is a loss of balance)
What are the most common causes of dizziness?
Postural hypotension
Medication side effect
Psychogenic
What is the typical history of someone with postural hypotension?
Dizziness comes on when rising from sitting/lying down