Vertigo/Dizziness Flashcards
Lightheadedness
- presyncopal feeling: prodromal symptoms of fainting or near faint
Vertigo
- Illusion of movement
- ACUTE
- due to assymmetry of of neural activity between the left and right vestibular nuclei
Peripheral Vertigo
- More common
- Inner ear etiology (e.g., semicricular canal debris, veistbular nerve infection, Meniere’s Disease)
- Positional testing: DELAYED HORIZONTAL NYSTAGMUS, away from affected ear
- Falls toward the affected ear
Central Vertigo
- Brainstem or cerebellar lesion (e.g., stroke affecting vestibular nuclei or posterior fossa tumor)
- Positional testing: IMMEDIATE NYSTAGMUS in ANY DIRECTION
Symptoms: (usually a combination of symptoms)
- directional change of nystagmus
- skew deviation
- Diplopia
- Dysmetria
- Usually the vertigo itself is less severe than peripheral vertigo
Cerebellar ataxia
lack of coordination of movement originating from the cerebellum
Sensory ataxia
- due to loss of sensory input into the control of movement (ataxia when eyes are shut)
Amitryptyline
- tricyclic antidepressant (TCA)
- well known for having lightheadedness due to large drop in BP, syncope
- avoid in elderly
Orthostatic Hypotension
Definition- a drop in Systolic BP of 20 mm Hg, or a drop in Diastolic BP of 10 mm Hg, within 3 mins of standing.
- Common symptoms- lightheadedness, visual gray out, generalized weakness, fatigue and falls
- Systemic OH: will have > 10bpm increase in pulse rate
- Neurogenic OH: will have fixed pulse rate
Normal response to standing
Upright posture results in the pooling of 500-1000mLof blood in the lower extremities and splanchnic circulation which initiates the following sequence:
- A rapid decrease in venous return to the heart
- diminished cardiac output and BP
- increases sympathetic outflow
- peripheral vasoconstriciton
Reflex/Vasovagal Syncope
- Neurocardiogenic: Response to a TRIGGER
- occurs acutely and transiently, due to episodic failure of sympathetic efferent vasoconstrictor action, in response to a trigger.
- pts are usually young and have a prodrome of diaphoresis, nausea, fatigue and pallor
Cortical Inputs for Balance
- visual confirmation of position,
2. non-visual confirmation of position (including proprioceptive/dorsal column and vestibular input/inner ear)
3. a normally functioning cerebellum
Romberg Sign
- If close eyes, will fall
- positive sign indicates either inner ear/propioceptive problem
Cold Calorics Test
- Used to determine if your brainstem is intact (brainstem is responsible for fast phase of nystagmus)
Remember COWS
- Cold water: Fast phase of nystagmus toward OPPOSITE ear
- Warm water: Slow phase of nystagmus toward SAME ear
Hallpike Maneuver Test
- Positive test: nystagmus will be seen going AWAY from affected ear
- Positive test indicates benign positional vertigo (more of inner ear problem then central)
Vestibular Neurontis / Acute Labyrinthitis
- Acute onset of severe vertigo that is PERSISTENT
- Peripheral characteristics
- Test: depressed caloric test on affected side