Tutorial #31: Dizziness Flashcards
Describe the sensation of “Vertigo”, and it’s most common trigger
“The room is spinning”
Triggered by head movement
Describe the senation of “Near Syncope”, and it’s most common trigger
“Feeling like you’re about to faint”
Triggered by standing (orthostatic) or warm environment, prolonged standing, seeing blood, straining (reflex/vasovagal)
Describe the sensation of Disequilibrium (x3)
“Position of your body parts is not precisely known”
“Sensation of falling”
“difficulty walking or standing”
With the HINTS exam, what 3 physical exam results are consistent with a PERIPHERAL cause of vertigo?
- Head impulse test -> the PRESENCE of refixation saccade
- Nystagmus -> unidirectional, horizontal
- Skew deviation -> absent
Therefore, if the patient does not have a refixation saccade OR has vertical / direction changing nystagmus OR has skew deviation, then it is a central cause of vertigo (You only need one of the three)
What 3 kinds of nystagmus suggest a central cause of vertigo?
- bidirectional nystagmus
- Nystagmus that is not inhibited by visual fixation on an object
- Nystagmus that lasts > 1 min OR fails to fatigue with repitition
In assessing vertigo, what are the first 3 steps you should take
Step 1: determine if vertigo is CNS in origin
Step 2: determine timing of vertigo episodes
Step 3: determine if it is triggered by head movement, or made worse by head movement
- CNS: new severe headache, neck pain. Brainstem dysfunction, cerebellar dysfunction, abnormal nystagmus, etc.
- if < 1 min, most likely BPPV, if lasting minutes to hours, might be TIA, vestibular migraine, meniere disease, etc. If Symptoms last for days, consider vestibular neuritis, stroke, or other CNS causes.
- Vertigo triggered by motion, most likely BPPV.
TIP: for vertigo that is persistent, you can use HINTS exam to determine if central or peripheral.
What is the most common cause of peripheral vertigo?
Benign paroxysmal positional vertigo (BPPV)
What is the confirmatory test for BPPV?
Dix-Hallpike test
What is the classical presentation of BPPV?
sudden abrupt onset of severe dizziness that occurs when changing head position, and lasts for < 1 min.
NOTE: Just because someone turns their head and their vertigo is worse, it does not mean its BPPV. Almost all causes of vertigo, whether peripheral or central, will worsen with head movement. BPPV is different because it is short, episodic, and triggered by head movement. It is confirmed with bedisde testing, such as the Dix-Hallpike, or other provocative maneuvers
What is the treatment for BPPV?
The Epley Maneuver or other respositioning techniques are first-line. Medications (i.e. Gravol or Serc) can be used as second line.
What is the classic presentation of acute vestibular neuritis?
can be precipitated by viral infection
Should not have any other focal neuro deficits
persistent vertigo that worsens with head movement, that can cause nausea/vomiting, and gait instability.
A HINTS exam would be helpful here to differentiate from a central cause.
What is the etiology of acute vestibular neuritis?
Inflammation of the vestibular-cochlear nerve
What is the treatment of acute vestibular neuritis?
Self-resolves, symptom management.
Steroids have mixed findings, and should only be used in very severe cases.
include antihistamines, and antiemetics
What are positive predictors of vertigo due to cerebrovascular disease (ie. Central cause of vertigo) (x5)
- Severe gait impairment
- cerebellar abnormalities on exam
- Positive HINTS test
- Facial droop
- motor function abnormalities (spasticity/weakness/etc)
Consider also if the patient has cardiovascular risk factors (HTN, T2DM, Smoking history, DLD)
Central vertigo caused by cerebrovascular disease is often due to inadequate perfusion to what area in the brain?
Inadquate perfusion to the posterior sections of the brain (ie. cerebellum or brainstem)