Initial Workup for Dizziness
The initial workup for dizziness should focus on determining the timing, triggers, and associated symptoms to categorize the dizziness into specific vestibular syndromes, which will guide further diagnostic testing and management.
Categorizing Dizziness by Timing and Triggers
- Focus on timing (acute vs. episodic vs. chronic) and triggers (positional vs. spontaneous) rather than the patient's subjective description of symptoms 1
- Categorize into one of four vestibular syndromes:
- Acute vestibular syndrome (AVS): acute persistent dizziness lasting days to weeks 1
- Triggered episodic vestibular syndrome: brief episodes triggered by specific actions (usually position changes) 1
- Spontaneous episodic vestibular syndrome: untriggered episodes lasting minutes to hours 1
- Chronic vestibular syndrome: dizziness lasting weeks to months 1
Key History Elements
- Duration and onset of symptoms (sudden vs. gradual) 1
- Positional triggers (head movements, lying down, rolling over in bed) 1
- Associated symptoms:
- Medication review (many can cause dizziness as a side effect) 2, 3
Physical Examination
For All Patients
- Vital signs including orthostatic blood pressure measurements 3, 4
- Cardiovascular examination 4
- Complete neurological examination 4
- Observation for spontaneous nystagmus 1
For Suspected Benign Paroxysmal Positional Vertigo (BPPV)
- Dix-Hallpike maneuver for posterior canal BPPV 1, 4
- Patient moved from sitting to supine with head extended and turned 45° to one side
- Positive test: delayed onset vertigo and characteristic nystagmus
- Supine roll test for horizontal canal BPPV 1
- Patient supine with head neutral, then quickly rotated 90° to each side
- Observe for horizontal nystagmus (geotropic or apogeotropic) 1
For Acute Vestibular Syndrome (AVS)
- HINTS examination (more sensitive than early MRI for stroke detection when performed correctly) 5:
- Head Impulse test: Abnormal (corrective saccade) suggests peripheral cause; normal suggests central cause 5
- Nystagmus assessment: Direction-changing nystagmus suggests central cause; unidirectional horizontal nystagmus suggests peripheral cause 5
- Test of Skew: Vertical misalignment suggests central lesion 5
Laboratory Testing
Imaging Studies
- Not routinely indicated for most cases of dizziness 1
- Consider brain imaging when:
- MRI brain with diffusion-weighted imaging is preferred over CT for suspected stroke 1
- CT temporal bone for suspected structural abnormalities of the ear 1
Common Pitfalls to Avoid
- Relying solely on the patient's description of dizziness type (vertigo, lightheadedness, etc.) rather than timing and triggers 6
- Overuse of imaging in patients with clear peripheral causes 1
- Failure to perform appropriate bedside tests like Dix-Hallpike maneuver or HINTS examination 5, 4
- Missing stroke in patients with isolated dizziness (4% of isolated dizziness cases are due to stroke) 1
- Prescribing vestibular suppressants without clear diagnosis, which may delay central compensation 2, 7
Initial Management Considerations
- For BPPV: Canalith repositioning procedures (e.g., Epley maneuver) 4, 7
- For vestibular neuritis: Consider short-term vestibular suppressants like meclizine 25-100 mg daily in divided doses 2, 7
- For Ménière's disease: Salt restriction and diuretics 4
- For central causes: Urgent neurological consultation 1