What is the appropriate emergency department evaluation and management algorithm for a patient presenting with dizziness?

Emergency Department Approach to Dizziness

Categorize dizziness by timing and triggers—not by the patient's subjective description—to identify specific vestibular syndromes that guide targeted examination and determine imaging needs. 1, 2

Initial Triage: Classify by Temporal Pattern

Focus on duration and triggers rather than vague descriptors like "spinning" or "lightheadedness," which are unreliable for diagnosis 1, 3:

• Seconds (<1 minute): Suggests BPPV, especially if triggered by head position changes 1, 2
• Minutes to hours: Suggests vestibular migraine or Ménière's disease 1, 2
• Days to weeks (acute vestibular syndrome): Suggests vestibular neuritis or posterior circulation stroke 1, 2
• Chronic (weeks to months): Consider medication side effects, anxiety/panic disorder, or posttraumatic vertigo 2, 3

Critical Pitfall to Avoid

75-80% of patients with posterior circulation stroke have NO focal neurologic deficits, so a normal neurologic exam does NOT exclude stroke 2, 3. Age >50 with vascular risk factors (hypertension, diabetes, atrial fibrillation, prior stroke) mandates urgent MRI even with normal exam 2, 3.

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Brief Episodic Vertigo (Seconds to <1 Minute)

Diagnosis: BPPV

Perform the Dix-Hallpike maneuver bilaterally as the gold standard diagnostic test 1, 2:

• Positive findings: 5-20 second latency, torsional upbeating nystagmus toward the affected ear, symptoms crescendo then resolve within 60 seconds 1, 2
• If Dix-Hallpike is negative, perform supine roll test to assess for horizontal canal BPPV (10-15% of cases) 2, 3

Management

Perform the Epley maneuver immediately after positive Dix-Hallpike 1, 2:

• 80% success rate after 1-3 treatments 1, 2
• 90-98% success with repeat maneuvers if initial treatment fails 1, 2
• No imaging or laboratory testing needed for typical BPPV with positive Dix-Hallpike and no red flags 1, 2
• Avoid vestibular suppressants (meclizine, dimenhydrinate, benzodiazepines)—they do not correct the mechanical pathology and delay central compensation 2, 4

Disposition

• Reassess within one month to document resolution 2
• Counsel about 10-18% recurrence at 1 year, up to 36% long-term 2
• Dizziness increases fall risk 12-fold in elderly patients; document fall history and provide safety counseling 2, 3

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Acute Vestibular Syndrome (Days to Weeks)

Key Differential: Vestibular Neuritis vs. Posterior Circulation Stroke

Approximately 25% of acute vestibular syndrome presentations are posterior circulation stroke, rising to 75% in high vascular-risk cohorts (age >50 with hypertension, diabetes, atrial fibrillation, prior stroke) 2, 3.

Physical Examination: HINTS

HINTS (Head Impulse, Nystagmus, Test of Skew) has 100% sensitivity for stroke when performed by trained practitioners, superior to early MRI (46% sensitivity) 1, 2:

• Central (stroke) features: Normal head impulse test, direction-changing or vertical nystagmus, skew deviation present 1, 2
• Peripheral features: Abnormal head impulse test (corrective saccade), unidirectional horizontal nystagmus, no skew deviation 1, 2

Critical Limitation

HINTS accuracy drops markedly when performed by non-experts 1, 2. In the ED, do not rely on HINTS alone—obtain urgent MRI for any high-risk patient regardless of HINTS results 2, 3.

Imaging Decisions

MRI brain without contrast (with diffusion-weighted imaging) is the preferred modality 1, 2:

• MRI diagnostic yield: ~4% vs. CT diagnostic yield: <1% for isolated dizziness 1, 2
• CT sensitivity for posterior circulation infarcts: only 10-20%—CT misses most posterior fossa strokes 1, 2

Urgent MRI Indications (Red Flags)

Obtain immediate MRI for any of the following 1, 2, 3:

• Age >50 with vascular risk factors (even with normal neurologic exam) 2, 3
• Focal neurologic deficits (dysarthria, limb weakness, diplopia, dysphagia, Horner's syndrome) 1, 2
• Abnormal HINTS examination (normal head impulse, direction-changing nystagmus, skew deviation) 1, 2
• Inability to stand or walk 1, 2
• Downbeating or purely vertical nystagmus 1, 2
• Direction-changing nystagmus 1, 2
• New severe headache accompanying dizziness 1, 2
• Sudden unilateral hearing loss 1, 2
• Unilateral or pulsatile tinnitus 2, 3
• Asymmetric hearing loss 2, 3

When Imaging Is NOT Needed

No imaging required for 1, 2:

• Low vascular risk (<50 years, no risk factors) with normal neurologic exam and peripheral HINTS pattern (performed by trained examiner) 1, 2
• Typical BPPV with positive Dix-Hallpike and no red flags 1, 2

Management Based on Diagnosis

Vestibular neuritis/labyrinthitis 1, 2:

• Supportive care and early vestibular rehabilitation therapy 1
• Short-course vestibular suppressants (antiemetics, benzodiazepines) only for severe acute symptoms 2, 5
• Vestibular rehabilitation significantly improves gait stability, especially in elderly or high fall-risk patients 1, 2

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Spontaneous Episodic Vertigo (Minutes to Hours)

Key Differentials: Vestibular Migraine vs. Ménière's Disease

Vestibular migraine accounts for 14% of all vertigo cases but is markedly under-recognized, especially in young patients 2, 3.

Distinguishing Features

Ménière's disease 1, 2:

• Fluctuating low-to-mid frequency sensorineural hearing loss (key distinguishing feature) 2, 3
• Aural fullness and tinnitus in affected ear 1, 2
• Episodes last 20 minutes to 12 hours 2, 3
• Requires comprehensive audiometry to document hearing pattern 2, 3

Vestibular migraine 1, 2:

• Headache with photophobia/phonophobia during or around vertigo episodes 1, 2
• No fluctuating hearing loss (stable or absent hearing loss) 2, 3
• Current or past migraine history, family history of migraine 2, 3
• Motion intolerance and light sensitivities help differentiate from Ménière's 2, 3

Imaging

MRI head and internal auditory canal WITH and WITHOUT contrast indicated for 2, 3:

• Chronic recurrent vertigo with unilateral hearing loss or tinnitus (to exclude vestibular schwannoma) 2, 3
• Suspected Ménière's disease requiring definitive diagnosis 2, 3

Management

Ménière's disease 1, 2:

• Salt restriction and diuretics 1, 2
• Intratympanic treatments for refractory cases 1, 2

Vestibular migraine 1, 2:

• Migraine prophylaxis and lifestyle modifications 1, 2

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Laboratory Testing

Routine laboratory testing is NOT indicated for isolated dizziness with normal vital signs and non-contributory examination 1.

Selective Testing

Order only when history/exam suggests specific abnormalities 1, 2:

• Fingerstick glucose immediately—hypoglycemia is the most frequently identified unexpected abnormality 2, 3
• Electrolytes if vomiting, diarrhea, or dehydration 1
• Thyroid function if affective symptoms 1

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Common Diagnostic Pitfalls

Avoid these errors 1, 2, 3:

1. Relying on patient's description of "spinning" vs. "lightheadedness"—focus on timing and triggers instead 1, 2
2. Assuming normal neurologic exam excludes stroke—75-80% of posterior circulation strokes lack focal deficits 2, 3
3. Using CT instead of MRI when stroke is suspected—CT misses most posterior circulation infarcts 1, 2
4. Overuse of imaging—routine imaging for isolated dizziness has <1% diagnostic yield 1, 2
5. Failing to perform Dix-Hallpike—BPPV is the most common cause (42% of all vertigo) and is treatable at bedside 2, 5, 4
6. Prescribing vestibular suppressants for BPPV—they are ineffective and delay recovery 2, 4
7. Not assessing fall risk in elderly patients—dizziness increases fall risk 12-fold 2, 3