Dizziness - Approach

a. The complaint of "dizziness" can be very frustrating for physicians because patients often use this term to refer to a variety of different processes, which need to be further distinguished by history and PE

b. The history should first focus on what type of sensation the patient is feeling (see some descriptors below)

c. Then consider common precipitants, including medications (cardiac meds, psych meds, anticholingerics, BPH meds), caffeine, etoh, nicotine; h/o recent head trauma ("whiplash" can cause dizziness)

d. One approach is to group dizziness into 1 of 4 categories, based on pt description:

i. Presyncope: "a feeling of nearly losing consciousness or blacking out" · Causes include orthostatic hypotension, arrhythmias, MI, carotid stenosis, etc.

ii. Vertigo: "a sense that the room is spinning" · Causes include BPPV, vestibular neuritis (viral infection of the vestibular nerve), labyrinthitis, Meniere's disease

iii. Disequilibrium: "feeling unsteady, off-balance or wobbly" · Many causes, including: stroke/TIA, peripheral neuropathy, central myelopathy Parkinson's disease, musculoskeletal problems, poor vision, acute intoxication

iv. Lightheadedness: vague symptoms, sense of being "disconnected" from the environment · More common causes include hyperventilation, anxiety

e. Physical exam findings that can help in diagnosis:

i. Check orthostatics: BP should be measured once in the supine position and again at least one minute after the patient stands. + orthostasis= decrease in SBP> 20 mm Hg, decrease in DBP> 10 mm Hg, or HR increase of >30 bpm.

ii. Dix-Hallpike maneuver: for BBPV, specific, but not sensitive

iii. Romberg test: if positive, is a sign of abnormal proprioception, either from neuropathy or posterior column disease (the pt does not know where their joint is in space and so uses visual clues--in the dark or with eyes closed they have difficulty) (not a cerebellar test)

iv. Observation of gait: ataxia is indicative of cerebellar dysfunction (gait is usually slow, wide-based, and irregular) Can also detect symptoms of parkinsonism

v. Cerebellar tests: also for ataxia (RAM, nystagmus, finger-to-nose, scanning speech etc.)

vi. Screening for peripheral neuropathy (sensation testing in LE) is also important in patients presenting with disequilibrium

f. Other diagnostic tests to consider:

i. EKG, Holter monitor, carotid doppler (if an underlying cardiac cause is suspected)

ii. More specific labs, if high suspicion (HgA1c, B12, thiamine, RPR etc. if history supports a particular underlying cause)

(Victoria Kelly MD, 12/9/10)