APPROACH TO THE NEUROLOGIC PATIENT
John G. Quinlan, M.D.
A. Anesthesia: Absence of sensation.
B. Coma: Depressed consciousness to the degree of
unresponsiveness to noxious stimuli.
C. Diplopia: Seeing two images where only one exists.
D. Vertigo: A hallucination of movement.
A. General approach to the neurologic patient.
B. Introductory comments vis-à-vis the neurologic history.
C. An outline for lecture.
APPROACH TO THE NEUROLOGIC PATIENT
A physician evaluating a patient with a potential neurologic problem must
try to answer three questions:
1. Is there a neurologic problem?
2. If so, where is the lesion in the nervous system?
3. What is the underlying pathophysiology?
1. IS THERE A NEUROLOGIC PROBLEM?
The initial and often most difficult part of the diagnostic process is to determine if
the presenting symptoms are due to a neurological disorder or non-neurologic
disease. The neurologic history is the most significant factor in making this
determination. For instance, fatigue is a common presenting complaint that may
be attributed by the patient or physician to dysfunction of the nervous system.
However, fatigue without any other neurologic complaints or findings is rarely due
to an identifiable neurologic disease. This first question is particularly difficult
since some patients with documented neurologic disease may also have
functional (non-neurologic) complaints. Pseudoseizures, for example, most
commonly occur in patients with documented seizures. A good rule of thumb is
always to give the patient the benefit of the doubt when deciding between
functional and neurologic disease.
2. WHERE IS THE LESION?
This question is actually composed of several questions:
• Is the neurologic problem in the central or peripheral nervous system?
• If central, does it involve the cerebral hemispheres, the posterior fossa
structures (brainstem or cerebellum), or the spinal cord?
• Is the problem focal, multifocal, or diffuse?
• If monofocal, is it on the left, right, or middle?
3. WHAT IS THE UNDERLYING PATHOPHYSIOLOGY?
This is the most difficult of the three questions. However, if one knows the time
course of the neurologic problem and can answer the second question, “Where is
the lesion?” the differential diagnosis can be narrowed considerably.
Time course can be divided into three categories:
• Acute = onset and evolution over minutes to hours
• Subacute = onset and evolution over days
• Chronic = onset and evolution over months
In addition, one can characterize a disease as transient, progressive, or stable.
Neurologic diseases that are focal and sudden in onset include stroke and
trauma. Neurologic diseases that are diffuse and sudden include toxic-metabolic
diseases (e.g. hypoglycemia), global cerebral ischemia (cardiac arrest), and
subarachnoid hemorrhage. Inflammatory and infectious diseases of the nervous
system have a subacute time course. Two classic focal and subacute neurologic
diseases are brain abscess and multiple sclerosis. The classic diffuse and
subacute neurologic diseases are meningitis and encephalitis. Toxic and
metabolic diseases can also have a diffuse and subacute presentation. The
classic focal and chronic neurologic lesion is a neoplasm, or something that acts
as an enlarging mass, such as a subdural hematoma. Finally, chronic and
diffuse deterioration usually represents a degenerative disease such as
THE NEUROLOGIC HISTORY
The neurologic history is the critical part of the neurologic evaluation. It is here
where most of the answers to the three main questions lie. The physician should
focus on the chief complaint and try to reconstruct a “videotape of the mind”
concerning the sequence of events. The time course of events is critical in
deciding the possible cause. Less precise words like dizziness and numbness
need to be clarified with other descriptors. If the patient has recurrent transient
events or spells, one should ask the patient to describe in detail, from start to
finish, a typical spell. Also, exact descriptions of the first and most recent spells
may be helpful. Because neurologic disease often affects the patient’s own
awareness of his or her problem, it is essential that the family be interviewed
whenever there is any question of cognitive or behavioral dysfunction. Also,
many neurologic diseases will have a profound effect upon the daily life of family
members, and they should be included in discussions with the patient.
I.` CHIEF COMPLAINTS
B. Unwanted Additions
II HISTORY OF PRESENT ILLNESS
B. Associated Symptoms
C. Aggravating and Alleviating Factors
III. PAST MEDICAL HISTORY
A. Major Diseases
B. Medications or Treatment
Past Medical History, Cont’d.
C. Think about A & B together
IV. SOCIAL HISTORY, FAMILY HISTORY
V. NEUROLOGICAL REVIEW OF SYMSTEMS