Course:PostgradFamilyPractice/ExamPrep/99 Priority Topics/Dizziness

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Dizziness - Key Features

1. In patients complaining of dizziness, rule out serious cardiovascular, cerebrovascular, and other neurologic disease (e.g., arrhythmia, myocardial infarction [MI], stroke, multiple sclerosis).

2. In patients complaining of dizziness, take a careful history to distinguish vertigo, presyncope, and syncope.

3. In patients complaining of dizziness, measure postural vital signs.

4. Examine patients with dizziness closely for neurologic signs.

5. In hypotensive dizzy patients, exclude serious conditions (e.g., MI, abdominal aortic aneurysm, sepsis, gastrointestinal bleeding) as the cause.

6. In patients with chronic dizziness, who present with a change in baseline symptoms, reassess to rule out serious causes.

7. In a dizzy patient, review medications (including prescription and over-the-counter medications) for possible reversible causes of the dizziness.

8. Investigate further those patients complaining of dizziness who have:
- signs or symptoms of central vertigo.
- a history of trauma.
- signs, symptoms, or other reasons (e.g., anticoagulation) to suspect a possible serious underlying cause.

Population: 3rd most common complaint among all outpatients and the single most common complaint among patients older than 75 years (in the US)
Incidence: 20 % of patients >60 yrs have dizziness severe enough to affect daily activities
Risk factors: In the elderly, 7 characteristics associated with dizziness:

- Anxiety trait
- Depressive symptoms
- Impaired balance (path deviation and time to turn circle greater than four seconds)
- Past myocardial infarction
- Postural hypotension (mean decrease in blood pressure 20 %)
- 5 or more medications
- Impaired hearing


History: – Ask open-ended questions

Clarify description of dizziness, i.e.: vertigo → out sensation of spinning - “whirling”, "tilting," or "moving." Vague dizziness, imbalance, or disorientation; presyncope → feeling faint like they’re going to pass out; disequilibrium → feeling of imbalance when standing/walking
Cardiac Sxs: chest pain, palpitations, dyspnea
History of cardiac disease, including cardiac dysrhythmias (tachycardias or bradyarrhythmias), coronary heart disease, congestive heart failure
Ask about psychiatric symptoms, often they don’t volunteer these symptoms
Time course – vertigo is usually not continuous even when caused by central lesion (vertigo that is continuous is often psychogenic); chronic dizziness needs re-evaluation to detect changes or need for further investigations
Provoking factors – i.e.: positional or postural changes
Aggravating factors – vertigo is almost always made worse with head movement
Associated Sx – nausea, vomiting, hearing loss, headache, photophobia, diplopia, dysarthria, dysphagia, weakness, or numbness (vertigo due to stroke almost always associated with these)
Drugs – i.e. antidepressants, calcium channel or beta-blockers


Cause of Dizziness varies with age - in elderly, higher incidence of central vestibular causes of vertigo (approx 20 %) most often stroke; psychiatric conditions and presyncope more so in young people
Common cause of presyncope/syncope: Orthostatic hypotension, cardiac arrhythmias, and vasovagal attacks (lack of spinning sensation cannot be used to exclude vestibular disease); disequilibrium – a musculoskeletal disorder interfering with gait, vestibular disorder, and/or cervical spondylosis; visual impairment can make the problem worse

Signs of Peripheral Cause of Vertigo Signs of Central Cause of Vertigo
Nystagmus Unidirectional, fast toward the normal ear, never reverses direction

Horizontal with a torsional component, never purely torsional or vertical
Suppressed effect of visual fixation

Sometimes reverses direction when patient looks in the direction of the slow phase

Can be any direction (vertical, horizontal or torsional)
No suppression of visual fixation

Neuro signs? No other neurologic signs Severe instability, patient often falls when walking
Hearing/tinnitus Deafness or tinnitus may be present No deafness or tinnitus


Periperhal causes of Vertigo Central Causes of Vertigo
Benign paroxysmal positional vertigo

Vestibular neuritis
Herpes zoster oticus (Ramsay Hunt syndrome)
Meniere's disease
Labyrinthine concussion
Perilymphatic fistula
Semicircular canal dehiscence syndrome
Cogan's syndrome
Recurrent vestibulopathy
Acoustic neuroma
Aminoglycoside toxicity
Otitis media

Migrainous vertigo

Brainstem ischemia
Cerebellar infarction and hemorrhage
Chiari malformation
Multiple sclerosis
Episodic ataxia type 2


Differentiating possible central causes of vertigo
Migrainous vertigo Recurrent episodes, last several minutes to hours History of migraine Central or peripheral characteristics Migraine headache accompanying or following vertigo, positive visual phenomena Usually none All tests are normal
Vertebrobasilar TIA Single or recurrent episodes lasting several minutes to hours Older patient, vascular risk factors, and or cervical trauma Central characteristics Usually other brainstem symptoms None MRI + DWI may demonstrate vascular lesion.
Brainstem infarction Sudden onset, persistent symptoms over days to weeks As above Central characteristics Usually other brainstem symptoms, especially lateral medullary signs None MRI will demonstrate lesion
Cerebellar infarction or hemorrhage Sudden onset, persistent symptoms over days to weeks Older patient, vascular risk factors, especially hypertension Central characteristics Gait impairment is prominent. Headache, limb dysmetria, dysphagia may occur None Urgent MRI, CT will demonstrate lesion


Treatment of Vertigo of peripheral cause (3 categories):

1. Specific to the underlying vestibular disease
2. Alleviating the acute symptoms of vertigo
anticholinergics (scopolamine patch behind ear q3days),
antihistamines (meclizine, dimenhydrinate, diphenhydramine)
Phenothiazine antiemetics (prochlorperazine, promethazine, metoclopramide, domperidone, ondansetron)
Benzodiazepines
3. Promoting recovery, i.e.: vestibular rehab – exercises such as moving head up and down, then side to side daily for several mins daily.


Cause SX Treatment
Meniere’s disease Vertigo lasting hours-days, hearing loss, tinnitus, aural fullness Avoidance of caffeine/alcohol

Low-dose HCTZ, anti-emetics
Serc

Acute labyrinthitis Vertigo lasting days, associated hearing loss, usually after URTI in which there is a middle ear effusion Rest, antiemetics, antibiotics if middle ear fluid is infected
Vestibular neuritis Vertigo lasting days

No hearing loss, no ear pain
Maybe after URTI
No other Sx

Rest, reassurance, antiemetics
Benign Positional Vertigo Vertigo lasting seconds

Associated with rolling head left or right or looking up || Reassurance, exercises – Dix Hallpike

Non – cardiovascular Cardiovascular
Reflex mechanisms

Vasovagal and vasodepressor syncope (neurocardiogenic syncope)
Micturition
Deglutition
Cough
Orthostatic hypotension
Dysautonomias
Fluid depletion
Illness, bed rest, reconditioning
Drugs - antidepressants, sympathetic blockers
Psychogenic
Hysterical
Panic disorder
Anxiety disorder
Undiagnosed seizures
Improperly diagnosed syncope - confusional states, e.g., due to hypoglycemia, stroke
Drug-induced loss of consciousness (consider alcohol, illicit drugs)

Cardiovascular disease

Arrhythmic causes
AV block with bradycardia (structural changes, drugs)
Sinus pauses/bradycardia (vagal causes, sick sinus syndrome, negative chronotropic drugs such as beta blockers and calcium channel blockers)
Ventricular tachycardia due to structural heart disease
Nonarrhythmic causes
Hypertrophic cardiomyopathy
Aortic stenosis
Syncope of unknown origin
About 50 percent of patients presenting to the hospital


Look for common causes of syncope if indicated by History

Major uncommon causes of syncope
Arrhythmic causes - SVT, Long QT, Idiopathic VTach, MI causing bradycardias and tachycardias, Right ventricular dysplasia
Nonarrhythmic causes - PE, Pulmonary hypertension, Dissecting aortic aneurysm, Subclavian steal, Atrial myxoma, Cardiac tamponade, Noncardiovascular disease,
Reflexes - Defecation, Glossopharyngeal, Postprandial, Carotid sinus hypersensitivity, Hyperventilation
Other - Migraine, Carcinoid syndrome, Systemic mastocytosis, Metabolic, Hypoglycemia, Hypoxia, Multivessel obstructive cerebrovascular disease

Study Guide

Dizziness

Resources

Uptodate (dizziness, vertigo)
Swanson's Family Medicine Review