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Ambulatory Care - Dizziness - Fast Facts | NEJM Resident 360

Undifferentiated dizziness is a high-risk symptom that can be caused by multiple organ systems. The assessment of dizziness focuses on key historical elements along with reassuring or alarming physical exam findings. Patients’ dizziness symptoms should guide the physical exam; however, patients may have difficulty precisely describing their symptoms to fit into discreet entities such as vertigo, disequilibrium, presyncope, lightheadedness, or unsteadiness. More recently, diagnostic approaches have focused on the timing and triggers of dizziness. In this section, we will cover the following:

• Diagnostic Approach to Dizziness

• Benign Paroxysmal Positional Vertigo (BPPV)

• Vestibular Neuritis

• Ménière Disease

• Persistent Postural-Perceptual Dizziness (PPPD)

Diagnostic Approach to Dizziness

Although vestibular disorders are almost always associated with dizziness, most causes of dizziness are due to nonvestibular disorders. A cross-sectional study in an emergency department population showed that the most common causes were vasovagal syncope, fluid and electrolyte disorders, vestibular neuritis/labyrinthitis, arrhythmia, anemia, transient ischemic attack, hypoglycemia, and migraine.

The diagnosis is based on a detailed history and relevant physical exam findings (described below). Laboratory test results and electrocardiography may be helpful. The following algorithm is one approach for evaluating dizziness.

Algorithm for Evaluating Dizziness

(Source: Adapted or reprinted with permission from Dizziness: Approach to Evaluation and Management, Feb 1, 2017, Vol 95, No 3, American Family Physician Copyright © 2017 American Academy of Family Physicians. All Rights Reserved Am Fam Physician 2017.)

Key History Details

• Ask about the context of the dizziness, including provoking and alleviating factors.

• Categorize the patient’s symptoms using their report of the timing (intermittent vs. continuous) and known triggers (precipitated by a certain movement or event):

• • triggered episodic vestibular syndrome: lasting seconds to minutes

  • spontaneous episodic vestibular syndrome: lasting minutes to hours

  • acute vestibular syndrome: spontaneous onset and constant vertiginous symptoms lasting hours to days

• Assess cardiovascular risk factors, which would increase suspicion for possible posterior circulation stroke affecting the vestibular system.

• Ask about associated hearing loss or tinnitus.

• Assess for additional neurologic symptoms that suggest a central cause.

• Take a complete social history including substance use.

• Review medications (especially antiepileptics, sedatives, antihypertensives, and analgesics, which are common causes of dizziness in the elderly).

Key Physical Exam Findings

• Examine vital signs; abnormalities include orthostatic hypotension.

• Perform cardiac exam; evaluate heart rate, rhythm, and murmurs.

• Perform the HINTS exam if you have a high suspicion for acute vestibular syndrome to help distinguish between potential causes. In the acute setting, the three maneuvers in the HINTS exam are more sensitive than MRI for differentiating central causes (i.e., stroke or transient ischemic attack) vs. peripheral causes of acute vestibular syndrome. (View a video demonstration of the HINTS exam here.)

  • Head Impulse: With the patient’s gaze fixed on an object in the distance, quickly turn the patient’s head 10 degrees in either direction. A normal result is the absence of catch-up saccades, which is also found in central vertigo. A corrective saccade (eyes turning with head and then returning to the distant object) is expected with peripheral causes.

  • Nystagmus: Vertical, torsional, and bidirectional nystagmus suggest a central cause. Spontaneous unidirectional horizontal nystagmus suggests a peripheral cause.

  • Test of Skew: With the patient looking straight ahead, alternate between covering and uncovering each eye. A vertical change in position of a covered eye after being uncovered is abnormal and suggests a central lesion.

• Perform the Dix–Hallpike maneuver if you suspect benign paroxysmal positional vertigo (see BPPV below).

• Evaluate gait: Inability to walk unsupported is a red flag for serious central pathology such as posterior circulation stroke.

• Perform a neurologic examination, including cranial nerve exam, strength examination, and sensory examination.

Pearls and PitfallsAccurate differentiation between acute vestibular syndrome and spontaneous episodic vestibular syndrome may not be possible when a patient presents early in the course of vestibular syndrome.Vestibular syndromes are generally worse with head movement.Cerebellar signs are not always present in cerebellar infarcts.Benign paroxysmal positional vertigo (BPPV) in the elderly can be triggered with position change, which can incorrectly lead you to suspect hypovolemia.Beware of anchoring bias toward a specific diagnosis before seeing the patient (e.g., automatically thinking of BPPV as the cause of dizziness).(Adapted from Diagnosing Stroke in Acute Dizziness and Vertigo. Stroke 2018.)

Benign Paroxysmal Positional Vertigo

Benign paroxysmal positional vertigo (BPPV) is a common cause of dizziness, usually triggered by head movement, that lasts a few seconds to minutes. There are three types of BPPV, depending on the involved semicircular canal: posterior, horizontal, and anterior. Posterior and horizontal canal BPPV account for almost all cases, with posterior being the most common presentation. BPPV is treated with repositioning maneuvers. A successful repositioning maneuver also rules out other diagnoses. Consider a central cause of dizziness if the patient has associated neurologic symptoms or certain features of nystagmus as outlined above in Key Physical Examination Findings.

• Posterior canal BPPV: The Dix–Hallpike maneuver (see figure 1 below) is used to diagnose posterior canal BPPV. The Epley maneuver (see figure 2 below) and the Semont maneuver (see figure 3 below) are used to treat posterior canal BPPV. The nystagmus in posterior canal BPPV develops after a short latency period and resolves within 60 seconds; it reverses direction when the patient sits up and diminishes with repeat testing (i.e., fatigability).

Figure 1. Use of the Dix–Hallpike Maneuver to Induce Nystagmus in Benign Paroxysmal Positional Vertigo Involving the Right Posterior Semicircular Canal. With the patient sitting upright (Panel A), the head is turned 45 degrees to the patient’s right (Panel B). The patient is then moved from the sitting position to the supine position with the head hanging below the top end of the examination table at an angle of 20 degrees (Panel C). The resulting nystagmus would be upbeat and torsional, with the top poles of the eyes beating toward the lower (right) ear (Panel D). (Source: Benign Paroxysmal Positional Vertigo. N Engl J Med 2014.)

****Figure 2.Epley’s Canalith-Repositioning Maneuver for the Treatment of Benign Paroxysmal Positional Vertigo Involving the Right Posterior Semicircular Canal: After resolution of the induced nystagmus with the use of the right-sided Dix–Hallpike maneuver (Panels A, B, and C), the head is turned 90 degrees toward the unaffected left side (Panel D), causing the otolithic debris to move closer to the common crus. The induced nystagmus, if present, would be in the same direction as that evoked during the Dix–Hallpike maneuver. The head is then turned another 90 degrees, to a facedown position, and the trunk is turned 90 degrees in the same direction, so that the patient is lying on the unaffected side (Panel E); the otolithic debris migrates in the same direction. The patient is then moved to the sitting position (Panel F), and the otolithic debris falls into the vestibule, through the common crus. Each position should be maintained until the induced nystagmus and vertigo resolve; always for a minimum of 30 seconds. (Source: Benign Paroxysmal Positional Vertigo. N Engl J Med 2014.)

Figure 3. Semont’s Repositioning Maneuver for Benign Paroxysmal Positional Vertigo Involving the Right Posterior Semicircular Canal. The patient is asked to sit upright (Panel A) and then lies on the side of the unaffected ear (Panel B). The patient is then rapidly guided in a cartwheel pattern through the upright position (without a pause) so that he or she is lying down on the opposite side (Panel C). The head should remain turned toward the left (unaffected) side throughout the maneuver. Finally, the patient is seated and the head is returned to the neutral position (Panel D). Each position should be maintained until the induced nystagmus and vertigo resolve, but always for a minimum of 2 minutes. (Source: Benign Paroxysmal Positional Vertigo. N Engl J Med 2014.) 

• Horizontal canal BPPV and posterior canal BPPV have similar manifestations, but horizontal canal BPPV is diagnosed with the supine log-roll test and treated with the Gufoni maneuver.

Vestibular Neuritis

Vestibular neuritis is a common cause of acute vestibular syndrome with preserved hearing. The vertiginous symptoms can be abrupt or gradual in onset and last for a few days. BPPV can develop in about 15% of patients after an episode of vestibular neuritis. Reactivation of type 1 herpes simplex virus is thought to be the primary etiology, but antivirals (e.g., valacyclovir) have not been shown to have a benefit. The mainstay of treatment is symptom control (e.g., antihistamines, anticholinergics, and benzodiazepines). Vestibular rehabilitation helps improve balance. Glucocorticoids may improve recovery.

Vestibular labyrinthitis refers to acute vestibular syndrome with hearing loss. It is thought to be closely related to vestibular neuritis; however, some experts advise caution with this diagnosis because the clinical picture can be a dangerous mimic of anterior inferior cerebellar artery ischemia. Consider specialist consultation for specialized vestibular testing.

Ménière Disease

Ménière disease can only be diagnosed after repeated episodes of vertigo with other otologic features. The American Academy of Otolaryngology—Head and Neck Surgery defines Ménière disease as follows:

• two or more spontaneous episodes of vertigo, each lasting 20 minutes to 12 hours

• audiometrically documented sensorineural hearing loss in the affected ear

• fluctuating aural symptoms (hearing, tinnitus, or fullness) in the affected ear

• not accounted for by another vestibular diagnosis

Endolymphatic hydrops is the presumed pathology of Ménière disease, but the underlying causes are yet to be clearly elucidated. Specialist referral is almost always needed to guide diagnostic workup. Once diagnosed, treatment is based on symptomatic management of acute episodes of vertigo, dietary modification (e.g., limiting salt, caffeine, and alcohol), and occasionally diuretics (theoretically to reduce endolymphatic hydrops), betahistine, and glucocorticoids. Surgery and ablative procedures may be considered.

Persistent Postural-Perceptual Dizziness

Persistent postural-perceptual dizziness (PPPD; formerly known as chronic subjective dizziness) is a diagnosis of exclusion characterized by at least 3 months of nonvertiginous, persistent dizziness or imbalance that occurs on most days and is often provoked by patient motion and upright positioning as well as moving objects in the environment. Patients often have comorbid anxiety or other psychiatric disease. PPPD is often preceded by central nervous system (CNS) trauma, infection, or other vestibular disorders. Vestibular rehabilitation, reassurance, cognitive behavioral therapy, and treatment of comorbid psychiatric conditions are the mainstays of treatment. Vestibular and balance rehabilitation therapy (VBRT) is an effective treatment for PPPD and other forms of dizziness and may be delivered via the internet or in person, typically by physical and occupational therapists.

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