What is the initial workup for a patient presenting with dizziness?

Initial Workup for Dizziness

Categorize dizziness by timing and triggers—not by the patient's vague description of "spinning" versus "lightheadedness"—to determine the specific vestibular syndrome and guide your physical examination and management. 1, 2, 3

Classification by Timing and Triggers

The most critical first step is determining which of four vestibular syndromes your patient has 1, 2:

• Triggered Episodic Vestibular Syndrome (t-EVS): Seconds to minutes of vertigo triggered by head movements—think BPPV 1, 2
• Spontaneous Episodic Vestibular Syndrome: Minutes to hours of spontaneous vertigo episodes—consider vestibular migraine or Ménière's disease 1, 2
• Acute Vestibular Syndrome (AVS): Days to weeks of constant, persistent dizziness—this is vestibular neuritis versus stroke until proven otherwise 1, 3
• Chronic Vestibular Syndrome: Weeks to months of persistent symptoms—medication side effects, anxiety, or posttraumatic vertigo 1, 2

Essential History Elements

Focus on these specific details rather than asking patients to describe their dizziness 1, 2:

• Duration and onset: Seconds (BPPV), minutes to hours (vestibular migraine, Ménière's), days to weeks (vestibular neuritis, stroke) 1, 2
• Triggers: Positional changes (BPPV), spontaneous (vestibular migraine, Ménière's) 1, 2
• Associated symptoms:
  • Hearing loss, tinnitus, or aural fullness suggest Ménière's disease 1, 2
  • Headache, photophobia, phonophobia suggest vestibular migraine 1, 2
  • Neurological symptoms (diplopia, dysarthria, numbness, weakness) suggest central causes 1, 3
• Vascular risk factors: Age >50, hypertension, atrial fibrillation, diabetes, prior stroke increase stroke risk to 11-25% even with normal neurologic exam 2, 3
• Medication review: Antihypertensives, sedatives, anticonvulsants, and psychotropic drugs are leading reversible causes 2
• Fall history: Document number of falls in past year—dizziness increases fall risk 12-fold in elderly 2

Physical Examination Protocol

Perform these specific maneuvers based on your timing/trigger classification 1, 2, 3:

For Triggered Episodic (Suspected BPPV):

• Dix-Hallpike maneuver: Look for 5-20 second latency, torsional upbeating nystagmus toward affected ear, symptoms resolving within 60 seconds 1, 2
• Supine roll test: Assesses horizontal canal BPPV 1

For Acute Vestibular Syndrome (AVS):

• HINTS examination (Head Impulse, Nystagmus, Test of Skew): 100% sensitivity for stroke when performed by trained practitioners, superior to early MRI (46% sensitivity) 1, 2, 3
• Critical pitfall: 75-80% of posterior circulation stroke patients have NO focal neurologic deficits—normal neurologic exam does NOT exclude stroke 2, 3

For All Patients:

• Observe for spontaneous nystagmus 1
• Complete neurologic examination including cranial nerves, cerebellar testing, gait assessment 3
• Orthostatic blood pressure measurement 4

Imaging Guidelines

Most patients with dizziness do NOT need imaging. 1, 2

Do NOT image for:

• Brief episodic vertigo with positive Dix-Hallpike test and typical BPPV features 1, 2
• Acute persistent vertigo with normal neurologic exam AND HINTS consistent with peripheral vertigo by a trained examiner 1, 2
• Nonspecific dizziness without vertigo, ataxia, or neurologic deficits 2

DO obtain MRI brain without contrast (NOT CT) for:

• Abnormal neurologic examination 1, 2, 3
• HINTS examination suggesting central cause 1, 2, 3
• High vascular risk patients with acute vestibular syndrome, even with normal neurologic exam 2, 3
• Unilateral or pulsatile tinnitus 2, 3
• Asymmetric hearing loss 2, 3
• Progressive neurologic symptoms 2

Critical imaging facts: CT head has <1% diagnostic yield for isolated dizziness and misses most posterior circulation infarcts; MRI with diffusion-weighted imaging has 4% diagnostic yield and is far superior 1, 2

Red Flags Requiring Urgent Evaluation

These mandate immediate imaging and neurologic consultation 1, 2, 3:

• Focal neurological deficits 1, 2, 3
• Sudden hearing loss 2, 3
• Inability to stand or walk 1, 2
• Downbeating nystagmus or other central nystagmus patterns 1, 2
• New severe headache accompanying dizziness 1, 2
• Failure to respond to appropriate vestibular treatments 1, 2

Laboratory Testing

Laboratory testing has very low yield in dizziness. 2

• Check fingerstick glucose immediately—hypoglycemia is the most frequently identified unexpected abnormality 2
• Consider basic metabolic panel only if history or examination suggests specific abnormalities 2
• Avoid routine comprehensive laboratory panels—they rarely change management 2

Common Pitfalls to Avoid

• Don't rely on patient's description of "spinning" versus "lightheadedness"—focus on timing and triggers instead 2
• Don't assume normal neurologic exam excludes stroke—75-80% of posterior circulation strokes have no focal deficits 2, 3
• Don't order CT when you suspect stroke—it misses most posterior circulation infarcts 1, 2
• Don't overuse imaging for clear peripheral causes—perform appropriate bedside tests first 1
• Don't forget that 4% of isolated dizziness is stroke—maintain appropriate vigilance 1
• Don't overlook medication side effects—they're a leading reversible cause of chronic dizziness 2