Initial Workup for Dizziness
The initial workup for dizziness should focus on timing and triggers rather than the patient's subjective description of symptoms to categorize dizziness into specific vestibular syndromes, which will guide further diagnostic testing and management. 1
Step 1: Categorize Dizziness by Timing and Triggers
Categorize dizziness into one of four vestibular syndromes 1:
- Acute Vestibular Syndrome (AVS): acute persistent dizziness lasting days to weeks
- Triggered Episodic Vestibular Syndrome: brief episodes triggered by specific movements
- Spontaneous Episodic Vestibular Syndrome: recurrent episodes without clear triggers
- Chronic Vestibular Syndrome: persistent dizziness lasting months
Focus on duration, onset, and positional triggers rather than subjective descriptions like "spinning" or "lightheadedness" 1, 2
Step 2: Key History Elements
- Document duration and onset of symptoms 1
- Identify positional triggers that worsen or provoke symptoms 1, 3
- Note associated symptoms 1:
- Hearing loss or tinnitus (suggests Ménière's disease)
- Neurological symptoms (headache, diplopia, dysarthria, numbness, weakness) may indicate central causes
- Assess medication history and potential drug interactions, especially with CNS depressants 4
Step 3: Physical Examination
- Observe for spontaneous nystagmus in all patients 1
- Perform the Dix-Hallpike maneuver and supine roll test for suspected BPPV 1, 2
- Conduct the HINTS examination (Head-Impulse, Nystagmus, Test of Skew) when indicated for AVS to distinguish peripheral from central causes 1, 2, 5
- Complete orthostatic blood pressure measurement 2, 3
- Perform a thorough cardiac and neurologic examination 2
Step 4: Diagnostic Testing
- Imaging studies are not routinely indicated for most cases of dizziness 1
- Consider MRI brain with diffusion-weighted imaging when neurological symptoms or signs are present, or when HINTS examination suggests a central cause 1
- CT temporal bone may be used for suspected structural abnormalities of the ear 1
- Laboratory testing is usually not required unless specific conditions are suspected 2, 3
Treatment Considerations
- For BPPV, canalith repositioning procedures (e.g., Epley maneuver) are the treatment of choice 2, 3
- Meclizine (25-100 mg daily in divided doses) may be used for vertigo associated with vestibular disorders 4
- Caution patients about drowsiness with meclizine and advise against driving or operating dangerous machinery 4
- Avoid meclizine in patients with asthma, glaucoma, or prostate enlargement due to anticholinergic effects 4
Common Pitfalls to Avoid
- Overusing imaging in patients with clear peripheral causes of dizziness 1
- Missing stroke in patients with isolated dizziness (occurs in 4% of cases) 1
- Relying solely on patient's subjective description of symptoms rather than timing and triggers 1, 2
- Failing to perform appropriate bedside tests like Dix-Hallpike or HINTS examination 1
- Not recognizing drug interactions with CNS depressants when prescribing meclizine 4