What is the appropriate workup and management for a patient presenting with dizziness, considering potential causes such as vertigo, lightheadedness, and orthostatic hypotension, and taking into account the patient's age, medical history, and current medications?

Workup of Dizziness

Classify dizziness by timing and triggers—not by patient descriptions of "spinning" versus "lightheadedness"—to guide your physical examination and distinguish benign peripheral causes from dangerous central pathology like stroke. 1, 2

Initial Classification by Timing and Triggers

Categorize patients into one of three vestibular syndromes based on when symptoms occur and what provokes them 1, 2, 3:

1. Triggered Episodic Vestibular Syndrome (seconds to minutes, provoked by head movement)

• Most likely diagnosis: Benign Paroxysmal Positional Vertigo (BPPV) 4, 2
• Key features: Vertigo lasting <1 minute, triggered by specific head position changes (rolling over in bed, looking up, bending forward) 4, 1
• Physical examination: Perform Dix-Hallpike maneuver—the gold standard diagnostic test 4, 1, 2
  • Positive test shows: 5-20 second latency before symptoms begin, torsional upbeating nystagmus toward the affected ear, symptoms that increase then resolve within 60 seconds 1, 2
• Imaging: No imaging needed for typical BPPV with positive Dix-Hallpike and no additional concerning features 1
• Treatment: Canalith repositioning procedures (Epley maneuver) as first-line, with 80% success after 1-3 treatments 1, 5, 6

2. Acute Vestibular Syndrome (days to weeks, constant symptoms)

• Differential diagnosis: Vestibular neuritis (peripheral) versus posterior circulation stroke (central) 4, 1, 2
• Critical distinction: 75-80% of patients with posterior circulation stroke have NO focal neurologic deficits on standard examination 1, 2
• Physical examination: Perform HINTS examination (Head-Impulse, Nystagmus, Test of Skew) 1, 2, 3
  • When performed by trained practitioners, HINTS has 100% sensitivity for detecting stroke versus 46% for early MRI 1, 2
  • Warning: HINTS is less reliable when performed by non-experts 1
• Imaging indications: MRI brain without contrast for 1:
  • Abnormal neurologic examination
  • HINTS examination suggesting central cause
  • High vascular risk patients (diabetes, hypertension, prior stroke, age >60)
  • New severe headache accompanying dizziness (requires immediate imaging and neurologic consultation)
• Avoid CT: CT head has only 20-40% sensitivity for posterior circulation infarcts and <1% diagnostic yield for isolated dizziness 1

3. Spontaneous Episodic Vestibular Syndrome (minutes to hours, unprovoked)

• Differential diagnosis: Vestibular migraine, Ménière's disease, transient ischemic attack 4, 1, 2
• Key distinguishing features:
  • Ménière's disease: Fluctuating hearing loss, tinnitus, aural fullness occurring just before, during, or after vertigo attacks lasting 20 minutes to 12 hours 4, 2
  • Vestibular migraine: Attacks lasting hours, history of migraines, photophobia more prominent than visual aura, hearing loss less likely 4, 1
  • Vestibular neuritis: Severe rotational vertigo lasting 12-36 hours with decreasing disequilibrium over 4-5 days, WITHOUT hearing loss, tinnitus, or aural fullness 4, 2
• Imaging indications: MRI brain with contrast for unilateral or pulsatile tinnitus, asymmetric hearing loss (to exclude vestibular schwannoma) 1, 2

Essential History Elements

Ask specific questions about 4, 1:

• Duration: Seconds, minutes, hours, or entire day
• Onset: Spontaneous versus provoked by head position, standing, or other triggers
• Associated symptoms: Hearing loss, tinnitus, aural fullness (suggests Ménière's disease or labyrinthitis) 4, 2
• Neurologic symptoms: Headache, diplopia, dysarthria, dysphagia, focal weakness, numbness (suggests central cause) 4
• Loss of consciousness: Never a symptom of Ménière's disease or peripheral vestibular disorders 4

Chronic Vestibular Syndrome (weeks to months)

When dizziness persists for weeks to months 1, 2:

• Medication review is essential: Antihypertensives, sedatives, anticonvulsants, psychotropic drugs are leading reversible causes 1
• Screen for psychiatric symptoms: Anxiety, panic disorder, depression are common causes of chronic dizziness 1
• Consider: Posttraumatic vertigo (history of head trauma), persistent BPPV, vestibular migraine, bilateral vestibulopathy 4, 1
• Imaging: Not routinely indicated unless red flags present; when needed, use MRI brain without contrast (not CT) 1

Red Flags Requiring Urgent Evaluation

The following mandate immediate imaging and neurologic consultation 1, 2:

• Focal neurological deficits (even subtle)
• Sudden hearing loss
• Inability to stand or walk
• New severe headache
• Downbeating nystagmus or other central nystagmus patterns
• Failure to respond to appropriate vestibular treatments

Orthostatic Hypotension Evaluation

For patients with presyncope or lightheadedness upon standing 4:

• Measure orthostatic vital signs: Blood pressure and heart rate supine, then at 1 and 3 minutes after standing 4
• Orthostatic hypotension defined as: Drop in systolic BP ≥20 mmHg or diastolic BP ≥10 mmHg within 3 minutes of standing 4
• Orthostatic tachycardia: Sustained heart rate increase ≥30 bpm within 10 minutes of standing (≥40 bpm in ages 12-19) 4
• Treatment options for orthostatic hypotension: Midodrine (alpha-1 agonist) increases standing systolic BP by 15-30 mmHg at 1 hour after 10 mg dose 7

Physical Examination Essentials

Perform the following based on clinical category 4, 1:

• Orthostatic vital signs (for presyncope/lightheadedness)
• Dix-Hallpike maneuver (for triggered episodic symptoms)
• HINTS examination (for acute vestibular syndrome when trained)
• Assess for nystagmus: Gaze-evoked nystagmus suggests central lesion 4
• Neurologic examination: Cranial nerves, cerebellar testing, gait assessment
• Otoscopic examination: Rule out middle ear pathology

Common Pitfalls to Avoid

• Do not rely on patient descriptions of "spinning" versus "lightheadedness"—focus on timing and triggers instead 1, 2
• Do not assume normal neurologic exam excludes stroke—75-80% of posterior circulation strokes have no focal deficits 1, 2
• Do not order routine imaging for isolated dizziness—CT has <1% diagnostic yield and misses most posterior circulation infarcts 1
• Do not order vestibular testing or imaging for straightforward BPPV with positive Dix-Hallpike—it delays treatment unnecessarily 1
• Do not use CT instead of MRI when stroke is suspected—CT sensitivity is only 20-40% for posterior circulation 1

Treatment Approach by Diagnosis

• BPPV: Epley maneuver (80% success after 1-3 treatments, 90-98% with repeat maneuvers); no medications needed 1, 5, 6
• Vestibular neuritis: Vestibular rehabilitation therapy; short-term vestibular suppressants (3-5 days maximum) 6
• Ménière's disease: Salt restriction, diuretics, intratympanic treatments for refractory cases 4, 6
• Vestibular migraine: Migraine prophylaxis and lifestyle modifications 4, 1
• Persistent dizziness after initial treatment: Vestibular rehabilitation therapy significantly improves gait stability, particularly in elderly patients or those with heightened fall risk 1