Dizziness and Vertigo
Perspective
Dizziness is an extremely common yet complex neurologic symptom that reflects a disturbance of normal balance perception and spatial orientation. An estimated 7.5 million patients with dizziness are seen each year in ambulatory care settings.1 Dizziness is also one of the most common principal complaints in the emergency department (ED) and is responsible for 2.5% of all ED visits.2 Among patients older than 60 years, 20% have experienced dizziness severe enough to affect their daily activity.3
“Dizziness” is an imprecise descriptor. Patients use the term to describe a variety of experiences, including sensations of motion, weakness, lightheadedness, unsteadiness, and depression. Even clinical experts do not uniformly agree to precise definitions, with some defining it broadly and others more narrowly. Dizziness is historically categorized into one of four categories based on symptom quality: vertigo (illusion of motion, often spinning), near syncope (feeling of impending faint), disequilibrium (loss of equilibrium when walking), and nonspecific dizziness.4
Dizziness can be caused by a myriad diseases. In older persons it is associated with a variety of cardiovascular, neurosensory, and psychiatric conditions and with the use of multiple medications.5 The challenge for the emergency physician is to sift out the rare patient with a dangerous underlying disorder from the many others who have benign causes.
Diagnostic Approach
It is often helpful to have dizzy patients describe the sensation they are experiencing without using the word dizzy. When this is done, one can generally categorize the dizziness into one of four categories: vertigo, near syncope, disequilibrium, and nonspecific dizziness. Vertigo is an illusion of motion, classically described as the room spinning. Some further subdivide this into objective vertigo (external environment is spinning) and subjective vertigo (spinning of self). Near syncope is usually described as feeling faint or lightheaded. Disequilibrium is usually described as an unsteady gait. Nonspecific dizziness is generally thought to be related to anxiety. The validity of this symptom-oriented method of categorizing dizziness has been recently challenged.6 For some patients, dizziness is simply a metaphor for malaise, representing a variety of causes, such as anemia, viral illness, or depression. The primary focus of this chapter is to provide a framework to differentiate vertigo from other types of dizziness and to identify potentially life-threatening causes of these symptoms.
If the patient has true vertigo, the clinician should determine whether the cause is a peripheral lesion, such as from the vestibular system, or a central process, such as cerebrovascular disease or a neoplasm. In most cases, peripheral disorders are benign, whereas central disorders have more serious consequences. Occasionally, as in the case of a cerebellar hemorrhage, immediate therapeutic intervention is indicated. Acute suppurative labyrinthitis is the only cause of peripheral vertigo that requires urgent intervention. Box 19-1 lists causes of vertigo and identifies the peripheral, central, and systemic diagnoses. Table 19-1 summarizes the different characteristics of peripheral and central vertigo.
Table 19-1
Characteristics of Peripheral and Central Vertigo
| CHARACTERISTIC | PERIPHERAL | CENTRAL |
| Onset | Sudden | Gradual or sudden |
| Intensity | Severe | Mild |
| Duration | Usually seconds or minutes; occasionally hours, days (intermittent) | Usually weeks, months (continuous) but can be seconds or minutes with vascular causes |
| Direction of nystagmus | One direction (usually horizontorotary) | Vertical, downbeating |
| Effect of head position | Worsened by position, often single critical position | Little change, associated with more than one position |
| Associated neurologic findings | None | Usually present |
| Associated auditory findings | May be present, including tinnitus | None |
Pivotal Findings
The medical history is used to determine if true vertigo exists. Although usually described as the environment spinning, any sensation of disorientation in space or sensation of motion can qualify as vertigo. Some nausea, vomiting, pallor, and perspiration accompany almost all but the mildest forms of vertigo. A sensation of imbalance often accompanies vertigo, and this can be extremely difficult to distinguish from true instability until after the patient’s symptoms have been reduced by treatment. True instability, disequilibrium, or ataxia indicates a higher likelihood of a central process.7 Because the labyrinth has no effect on the level of consciousness, the patient should not have an associated change in mentation or syncope.
Head injury can cause vertigo occasionally from intracerebral injury and more commonly from labyrinth concussion. Neck injury can cause vertigo from vertebral artery dissection, resulting in posterior circulation ischemia.8
Are there associated neurologic symptoms?
