Dizziness…the good and the ugly…

The differential diagnosis of vertigo can be broken into peripheral and central causes. It is imperative the Emergency Physician consider central causes of vertigo.

 

Signs/ Symptoms Differentiating Peripheral and Central Vertigo

Peripheral Central
Onset Sudden or Insidious Sudden
Severity of Vertigo Intense Spinning Ill-defined, may be severe or less intense
Prodromal Dizziness Occurs in up to 25%, often single episode Occurs in up to 25%, recurrent episodes suggest TIA’s
Intolerant of head movements/Dix-Hallpike Maneuver Yes Varies, but often intolerant
Associated Nausea/Diaphoresis Frequent Variable, but often frequent
Auditory Symptoms Points to peripheral causes May be present
Proportionality of Symptoms Usually proportional Often disproportionate
Headache/Neck Pain Unusual More likely
CNS signs/symptoms Absent Usually present
Head Impulse Test Abnormal Often normal
Nystagmus Horizontal Vertical/direction-changing
HINTS Testing Negative Abnormal in at least 1 out of 3 tests

Myths In Emergency Medicine Diagnostic Imaging For Dizziness

“Doctor, I’m feeling dizzy…” What you need to know:

  • CT is worthless and expensive in the evaluation of dizziness.
  • MRI has much better utility but is often unnecessary for the complaint of dizziness.
  • Nystagmus is an unreliable sign and does not differentiate serious neurological disease from other causes of dizziness.
  • Gait instability or imbalance, other subtle neurological findings, and age >60 years are predictors of stroke or other serious neurological diseases causing dizziness – Do an MRI NOT CT
  • Isolated dizziness is very unlikely to be serious or to require an extensive diagnostic evaluation.

Head CT is poor screening tool for ED

“Our results suggest that most patients presenting with syncope or dizziness to the emergency department may not benefit from head CT unless they are older, have a focal neurologic deficit, or have a history of recent head trauma,”

Epley’s Maneuver

Benign paroxysmal positional vertigo (BPPV) is the likely cause in patients reporting brief recurrent attacks of dizziness triggered by changes in head position. It is important to recognize this cause because it can be readily treated at the bedside and because identification of the key features is the most effective way to exclude a central nervous system cause of positional dizziness. Important points about BPPV are that; a) the dizziness episodes last < 1 minute – Sometimes nausea or a mild light headedness can persist longer than 1 minute, but any patient reporting positional dizziness lasting longer than 1 minute should be carefully scrutinized for other potential causes. b) patients are normal in between episodes The Epley manoeuvre, a curative bedside manoeuvre, can then be used to reposition the debris in the semicircular cannals that is responsible for BPPV.