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ability to perform basic functions, such as respiration and temperature control.

Blood pressure, heart rate, respiratory rate and panern (see Table

2-3), temperature, and other vital signs from invasive monitoring (see

Appendix III-A) are assessed continuously or hourly to determine

neurologic and hemodynamic stability.

Clinical Tip

The therapist should be aware of blood pressure parameters

determined by the physician for the patient with neurologic

dysfunction. These parameters may be set greater than normal to maintain adequate perfusion to the brain or lower than normal to prevent further injury to the brain.

Cranial Neroes

CN testing provides information about the general neurologic status

of the patient and the function of the special senses. The results assist

in the differential diagnosis of neurologic dysfunction and may help in

determining the location of a lesion. CNs I through XII are tested on

admission, daily in the hospital, or when there is a suspected change

in neurologic function (Table 4-13).

Vision

Vision testing is an important portion of the neurologic examination,

because alterations in vision can indicate neurologic lesions, as illustrated in Figure 4-7. In addition to the visual field, acuity, reflexive, and ophthalmoscopic testing performed by the physician during CN

assessment, the pupils are further examined for the following:

• Size and equality. Pupil size is normally 2--4 mm or 4--8 mm in

diameter in the light and dark, respectively.13 The pupils should be

Table 4-13. Origin, Purpose, and Testing of the Cranial Nerves

N

00

00

Nerve/Origin

Purpose

How to Test

SignslSymproms of impairment

,.

Olfactory (CN III

Sense of smell

Have the patiem close one

Anosmia

�

cerebral c ortex

nostril, and ask the

\?

patient to sniff a mild-

'"

m

smelling substance and

J:

,.

idemify it.

z

"

Optic (CN IIllthalamlls

Central and peripheral

Acuity: Have the patient

Blindness

g

vision

cover one eye, and ask

'"

patient to read a visual

"

'"

chart.

�

:I:

Fields: Have the patient

�

cover one eye, and hold

!j

an object (e.g., pen cap) at

r

arm's length from the

J!

!i!

patient in his or her

,.

peripheral field. Hold the

�

parient's head steady.

Slowly move the object

centrally, and ask the

patiem to state when he

or she first sees the object.

Repeat the process in all

quadrants.