Examination of the Dizzy Patient



Ovid: Field Guide to the Neurologic Examination

Authors: Lewis, Steven L.
Title: Field Guide to the Neurologic Examination, 1st Edition
> Table of Contents > Section 3
– Neurologic Examination in Common Clinical Scenarios > Chapter 44 –
Examination of the Dizzy Patient

Chapter 44
Examination of the Dizzy Patient
GOAL
The main goal of the history and examination of the
patient with dizziness is to determine whether the patient’s dizziness
is actually due to lightheadedness, imbalance, or vertigo, paving the
way for the most appropriate further investigation and treatment.
PATHOPHYSIOLOGY OF DIZZINESS
Patients may use the word dizzy to describe several different symptoms, including a sensation of lightheadedness, imbalance, or movement (vertigo).
  • Lightheadedness implies a sensation of impending loss of consciousness, also called presyncope.
    Episodic lightheadedness suggests episodes of global cerebral
    hypoperfusion, such as from cardiac causes or orthostatic hypotension.
  • Imbalance is
    a sensation of gait instability (disequilibrium) that may range from
    subtle to severe. Patients may especially interpret their imbalance as
    “dizziness” when their gait dysfunction is subtle, because they may be
    unaware that their feeling is really an imbalanced sensation.
  • Vertigo
    refers to an illusory sensation of motion. Most patients with vertigo
    describe a feeling of rotation of the environment or in their head, but
    vertigo can also include any feeling of movement, such as a feeling of
    tilting or swaying. Vertigo occurs due to disorders of the vestibular
    system, either peripheral (the inner ear or the vestibular nerve) or
    central (brainstem or cerebellum).
TAKING THE HISTORY OF A DIZZY PATIENT
When evaluating a patient with a complaint of dizziness,
the main goal of the history is to try to determine what the patient
means by “dizzy.” The first step is to simply ask the patient, “What do
you mean by dizzy?” Let the patient tell you, in his or her own words,
what he or she means, and try to avoid putting words in the patient’s
mouth. Additional clues to the cause of dizziness that can be gleaned
by the history alone are listed below.
Lightheadedness
  • Patients with lightheadedness
    (presyncope) usually can describe their feeling as that of
    “lightheadedness” or a feeling “like I might pass out.” A history of
    any of the episodes progressing to true loss of consciousness is
    further evidence that the patient’s symptoms fit into this category of
    dizziness.
  • Ask about any associated cardiac
    symptoms, such as palpitations or chest pain, although the absence of
    these symptoms does not exclude a cardiac cause.
  • Lightheadedness occurring only after standing suggests orthostatic hypotension.

P.148


Imbalance
  • Patients with imbalance as the cause of
    their dizziness usually can describe their feeling as something like an
    “off-balanced” or “unsteady” sensation, and they should be symptomatic
    when standing or walking but not when lying or sitting.
  • The historical finding of worsened
    imbalance when standing in the dark (e.g., walking to the bathroom at
    night) or with eyes closed (e.g., in the shower) suggests
    proprioceptive dysfunction. Even in the absence of a positive Romberg
    test, these historical clues are strongly suggestive of proprioceptive
    problems, such as can occur due to peripheral neuropathies or spinal
    cord (posterior column) problems.
Vertigo
  • Patients with vertigo usually can describe their feeling as that of a spinning, moving, or tilting sensation.
  • Ask about any associated brainstem
    symptoms, such as double vision, or numbness or weakness of the face or
    of the extremities. The presence of brainstem symptoms in patients with
    vertigo is strongly suggestive of brainstem dysfunction (e.g.,
    ischemia) as the cause; their absence, however, doesn’t exclude the
    possibility of a central (brainstem or cerebellar) cause of vertigo.
  • Hearing complaints, such as unilateral
    hearing loss or tinnitus, occurring in association with vertigo suggest
    a peripheral labyrinthine disorder.
  • Paroxysmal vertigo brought on by changes
    in head position, such as when turning, bending over, or rolling over
    in bed, is highly suggestive of the clinical syndrome of benign
    paroxysmal positional vertigo (BPPV), which occurs due to the presence
    of calcium carbonate crystals floating in one of the semicircular
    canals.
  • Nausea and vomiting is a nonspecific accompaniment of vertigo and can occur with vertigo of peripheral or central etiologies.
HOW TO EXAMINE THE DIZZY PATIENT
After obtaining the history, you should hopefully have a
pretty good idea whether your patient’s dizziness is due to
lightheadedness, imbalance, or vertigo. The examination is then
performed to find evidence to support or refute your hypothesis and
provide further information regarding possible etiologies. Listed below
are specific examination elements, depending on your clinical
suspicion, that can be helpful.
Lightheadedness
  • In the patient with episodic
    lightheadedness, be certain (as in any new patient visit) to obtain
    your patient’s blood pressure and pulse, and also perform a bedside
    cardiac examination.
  • Check lying and standing blood pressure in any patient whose symptoms suggest the possibility of orthostatic hypotension:
    • Have the patient lie flat in bed for a few minutes, then check the patient’s supine blood pressure and pulse.
    • Ask the patient to stand. (It’s usually
      not necessary to check a sitting blood pressure and pulse, unless the
      patient can’t tolerate the standing position.)
    • After the patient has been upright for approximately 2 to 3 minutes, check the patient’s standing blood pressure and pulse.
  • P.149


  • A standing decrease in systolic blood
    pressure by 20 mm Hg or more is consistent with orthostatic
    hypotension; there may or may not be an increase in pulse depending on
    the cause. Patients whose orthostasis is due to volume depletion would
    be expected to have the ability to mount a tachycardic response to the
    blood pressure drop; however, patients with autonomic insufficiency may
    have profound orthostatic drops in blood pressure with little or no
    increase in pulse rate. When orthostatic hypotension is found, it is
    also important to ask the patient if any symptoms during the test
    re-created his or her presenting complaints.
Imbalance
  • In the patient with possible imbalance as
    the cause of dizziness, pay particular attention to assessing gait and
    look for abnormalities of motor, sensory, or cerebellar function.
  • Look for proprioceptive loss in the toes or a Romberg sign (see Chapter 32,
    Romberg Testing); however, it is more common to discover subtle
    Romberg-like findings by history (worsened imbalance in the dark or in
    the shower) than to detect proprioceptive loss or a Romberg sign on
    examination. Often, the only examination clue to neuropathic or
    posterior column dysfunction is vibratory loss in the feet.
Vertigo
  • Patients with vertigo due to acute
    cerebellar or brainstem dysfunction may have significant gait ataxia
    and may even be unable to walk without assistance (see Chapter 39, Examination of Gait).
  • Patients with peripheral vestibular
    disorders may have some difficulty with gait, particularly while
    acutely vertiginous, but usually not with the severity of some patients
    with an acute central (e.g., cerebellar) process. Patients with
    vestibular problems may feel pulled and lean toward the side of the
    vestibular dysfunction, but they can still usually walk without a
    significant problem.
  • Nystagmus may be seen with vertigo of
    central or peripheral origin. Depending on the cause and severity of
    the problem, nystagmus can be seen in primary gaze (i.e., while the
    patient is looking forward) or when eye movements are examined (i.e.,
    in horizontal or vertical gaze). Features of nystagmus that are
    suggestive of central versus peripheral labyrinthine disorders are
    summarized in Table 44-1. The most important
    discriminating feature of nystagmus is that purely vertical nystagmus
    is strongly suggestive of central (cerebellum or brainstem) causes of
    vertigo.
  • Patients whose clinical symptoms suggest BPPV should undergo positional testing with the Dix-Hallpike test (Fig. 44-1). The purpose of the Dix-Hallpike test (also called the Bárány maneuver or the Nylen-Bárány maneuver)
    is to look specifically for evidence to support the diagnosis of BPPV
    in patients who are clinically suspected of having this syndrome based
    on the history. It is not a general test of vestibular function. To
    perform the Dix-Hallpike test:
    • Inform the patient that you’ll be
      attempting to produce the patient’s vertigo with the maneuver, ask the
      patient to try to keep his or her eyes open throughout, and explain the
      procedure to the patient.
    • Have the patient sit up on the examining
      table (or in bed). Make sure the patient is sitting in a position that
      will allow the head to be extended off of the table when the patient
      lies down.
    • Turn the patient’s head to the side
      (right or left) that you think is most likely, by history, to produce
      vertigo when the patient lies down [i.e., if

      P.150


      the
      patient says that turning his or her head to the right in bed usually
      provokes vertigo, test the patient initially with the head to the right
      (Fig. 44-1A)].

      TABLE 44-1 Features of Nystagmus of Central versus Peripheral Origin

      Localization of
      Acute Dysfunction

      Type of Nystagmus
      That May Be Present

      Direction of Nystagmusa in Relation to
      Direction of Gaze

      Central (cerebellum or brainstem)

      Vertical or horizontal; may have rotatory component

      Nystagmus may
      change direction with change in direction of gaze (e.g., nystagmus may
      be left-beating with gaze to the left and right-beating with gaze to
      the right)b

      Peripheral (labyrinth)

      Usually horizontal; may have rotatory component

      Although
      nystagmus might only be present when looking in one direction, if it is
      present in both left and right gaze, the nystagmus always beats in the
      same direction; peripheral nystagmus is most prominent when gazing in
      the direction of fast phasec

      a The direction of nystagmus is named after the fast phase (the direction it is beating in).

      b
      The finding of changing direction of nystagmus with change in gaze is
      only helpful in supporting a central origin when present; acute
      cerebellar disorders may cause nystagmus in only one direction of gaze,
      appearing similar to peripheral nystagmus.

      c In peripheral vestibular disorders, the direction of the slow phase points to the side of the vestibular lesion.

      Adapted from Hotson JR, Baloh RW. Acute vestibular syndrome. N Engl J Med 1998;339:680-685.

    • While holding the patient’s head in your
      hands, rapidly move the patient down to the head-hanging position, all
      the while keeping his or her head turned to the side (Fig. 44-1B).
    • Observe the patient in that position for
      at least 10 seconds, watching for a complaint of vertigo. Look at the
      patient’s eyes for nystagmus during this time, especially during any
      complaint of vertigo. You don’t need to check eye movements; just
      observe the open eyes for the presence of nystagmus.
    • Sit the patient back up.
    • If the initial maneuver brought on
      vertigo, consider performing the maneuver again, looking for the
      typical extinction of the response with repeat testing; however, this
      additional confirmation is usually not necessary.
    • If the initial maneuver did not bring on
      vertigo, sit the patient back up and repeat the procedure with the head
      turned in the opposite direction.
  • Characteristic abnormalities on the Dix-Hallpike maneuver supportive of a diagnosis of BPPV include the following:
    • Recapitulation of the patient’s symptoms
      of positional vertigo, typically lasting up to approximately 30
      seconds. The vertigo experienced by patients with BPPV during the
      Dix-Hallpike maneuver is usually not subtle; patients with this
      syndrome are often distressed by the vertigo evoked by this test.
    • A characteristic latency to the onset of the vertigo (and nystagmus) that may be delayed up to 10 seconds.

      P.151


      Figure 44-1
      Dix-Hallpike testing for benign positional vertigo with the head to the
      right. See text for details. (Redrawn from Furman JM, Cass SP. Benign
      paroxysmal positional vertigo. N Engl J Med 1999;341:1590-1596.)
    • A burst of primarily rotatory (eye
      rotating toward the dependent ear) nystagmus during the vertigo. The
      finding of nystagmus, however, although supportive, is of lesser
      diagnostic importance than the vertigo brought on during the maneuver;
      this is mainly because it’s often hard to visualize the eyes during the
      patient’s distress.
    • Extinction of the response [i.e., if the
      procedure is repeated with the head turned in the same direction, the
      vertigo (and nystagmus) is less severe].
ADDITIONAL COMMENTS
The distinction between central and peripheral causes of
acute vertigo is not always easy on the basis of the history and
examination. The finding of brainstem dysfunction or purely vertical
nystagmus strongly supports a central cause, but their absence does not
exclude a central (e.g., acute cerebellar) process.

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More