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Flashcards in dizziness Deck (41):
1

vertigo
peripheral vs central

Sensation of motion in the absence of actual motion
Exaggerated sense of motion in response to body movement

Peripheral
More common
“Inner ear”

Central
Worse pathology
Brain stem or cerebellar in origin

2

body orientation

visual:
spacial orientation

vestibular system: Indicates the body orientation relative to the gravity

proprioceptive: Relates body movements
Indicates the position of head relative to the body


3

vestibular system: otoliths are in the...

otolith organs

is a structure in the saccule of the inner ear
otholith organs: saccule and utricle

Utricle is sensitive to a change in horizontal movement

Saccule provides information about vertical acceleration

*if get stuck-->vertigo

4

semicircular canals

Sense orientation of movement
Filled with endolymph
Movement of endolymph results in sensory input
Dysfunction results in nystagmus

Abnormalities within the vertical canals (anterior or posterior) result in vertical/torsional nystagmus

Abnormalities within the horizontal canal (lateral) result in horizontal nystagmus

5

visual + vestibular

vestibulo-occular reflex (VOR)
Maintains clear vision with movement
Abnormality caused by aberrant stimulation
Abnormality caused by lesion
Results in vertigo / Nystagmus

6

nystagmus

Rhythmic movement of eyes
Fast and slow component
Direction is named by the fast component
Slow component is generated from the canals
( resulting in eye movement away from canals )


7

caloric reflex test

"COWS" ??
Test of the vestibulo-ocular reflex that involves irrigating cold or warm water external auditory canal.

8

caloric reflex test in pts w. cerebral damage

the fast phase of nystagmus will be absent as this is controlled by the cerebrum. As a result, using cold water irrigation will result in deviation of the eyes toward the ear being irrigated. If both phases are absent, this suggests the patient's brainstem reflexes are also damaged and carries a very poor prognosis

9

COWS

Cold Opposite, Warm Same.Cold water = FAST phase of nystagmus to the side Opposite from the cold water filled earWarm water = FAST phase of nystagmus to the Same side as the warm water filled earIn other words: Contralateral when cold is applied and ipsilateral when warm is applied

10

peripheral vestibular disease



Three common peripheral vestibular disorders

Abrupt onset
Intense sensation of spinning
Worsened by rapid movement
Associated with nausea



Vestibular neuritis
Meniere disease
Benign paroxysmal positional vertigo


11

Meniere disease

Distention of the endolymphatic compartment
Unknown cause
( head trauma, syphilis )
Vertigo ( minutes to hours )
Associated with hearing loss
Tinnitus, fullness in ears

tx with diuretics, low salt
(enolymphatic hydrops)

12

Vestibular neuritis

Unknown cause ( Viral )
Intense vertigo
(several days )
Positional nystagmus
Very debilitating

tx: Supportive care
Diazepam
Meclizine* (nondrowsy dramamine)
(Vestibular suppressant

13

BPPV: benign paroxysmal positional vertigo

Inappropriate activation of semicircular canal
Vertigo ( minutes )
*Provoked by head movement
( latency after movement )
Central lesions have no latency

14

central disease

Gradual onset
More severe and debilitating
Variable nystagmus
Vertical / without latency
*Worsened by rapid movement (with periph as well)

15

central causes

Cerebellar infarct
MS
neoplasm
vert. art. dissection

16

non vestibular dizzines

Imbalance
Syncope
Near syncope

17

syncope

transient loss of consciousness

18

near syncope

light headedness with concern of impending “transient loss of consciousness”

19

disequilibrium

feeling of unsteadiness, imbalance

20

dizzy hpi

Do not bias the patient’s response “leading questions”
Describe the initial response
Identify the onset
Identify a noted trigger (med?)
Describe the duration
Review medication
Review past medial history
Identify the “type” of vertigo......

21

ask pt...

Onset
CNS symptoms
Tympanic membrane
Pattern
Hearing loss
Tinnitus
Increased by position
Nystagmus
Fatigue
Associated with nausea / diaphoresis

22

see chart

slide 18

23

may have an affected, retracted TM in

peripheral
normal in central

24

older dizzy pt, eval. for ??

central disease:
blood thinners (hemorrhage)
HTN, hypotension (not enough CO)
CV-
arrhythmia: afib, vfib (wtws?, shockable rhythm)
bradycardia
SVT

e-lyte abnormalities: hyper/hypo?kalemia (transient paralysis)
hyponatremia
if hyper-dehydrated

hypoglycemia
hyperglycemia

25

PE: ear

OM
cholesteotoma

26

cholesteatoma

Destructive and expanding growth consisting of keratinizing squamous epithelium in the middle ear
two types: congenital and acquired.
Acquired cholesteatomas: more common, can be caused by pathological alteration of the ear drum leading to accumulation of keratin within the middle ear
-keratin should not be in middle ear, just EAC
tx. with microsurgery

27

PE: hearing

webber, rinne

28

webber

Identify
unilateral conductive hearing loss
(middle ear hearing loss)
unilateral sensorineural hearing loss
(inner ear hearing loss)

29

PE: neuro

Facial paresis
Truncal ataxia
cerebellar exam
optic
dix halpike

30

romberg: proprioception problem

The Romberg test is used to investigate the cause of loss of motor coordination (ataxia). A positive Romberg test suggests that the ataxia is sensory in nature, that is, depending on loss of proprioception. If a patient is ataxic and Romberg's test is not positive, it suggests that ataxia is cerebellar in nature, that is, depending on localized cerebellar dysfunction instead.

31

dix-hallpike

The Dix–Hallpike test is performed with the patient sitting upright with the legs extended. The patient's head is then rotated by approximately 45 degrees. The clinician helps the patient to lie down backwards quickly with the head held in approximately 20 degrees of extension. This extension may either be achieved by having the clinician supporting the head as it hangs off the table or by placing a pillow under their upper back. The patient's eyes are then observed for about 45 seconds as there is a characteristic 5–10 second period of latency prior to the onset of nystagmus.

32

optho 1

nystagmus

33

goals of meds

Elimination of vertigo
Enhancement of vestibular compensation
Reduction of associated symptoms

34

antiemetics (peripheral)

hydroxyzine (reglan)
metoclopramide

35

benzos

diazepam
clonazepam

36

antihistamines

diphenhydramine

37

Ca2+ antags

nimodipine

38

anticholinergics

scopolamine
-motion sickness, chemo nausea, dementia pts: mild sedative

39

ancillary test for classic inducible peripheral vertigoGradual onset
More severe and debilitating
Variable nystagmus
Vertical / without latency
Worsened by rapid movement

Most patients do no require emergent laboratory work up, typ. don't need lab testing
-exp: on diuretic
*do EKG

Detailed testing for ENT

CT/ MRI ( central disease )
PT

40

peripheral

Abrupt onset
Intense sensation of spinning
*Worsened by rapid movement
Associated with nausea

41

central

Gradual onset
More severe and debilitating
Variable nystagmus
Vertical / without latency
*Worsened by rapid movement