Page 230 - Critical Care Nursing Demystified

Chapter 5 CARE OF THE PATIENT WITH NEUROLOGICAL NEEDS 215

The autonomic or involuntary nervous system (ANS) is also known as the
motor division in which motor neurons connect the CNS with smooth muscle
and cardiac muscle, as well as the glands and internal organs. The ANS regulates
functions of the heart, respiratory, and gastrointestinal activity. The ANS divi-
sion includes the sympathetic and parasympathetic branches. Motor fibers are
known as efferent fibers that transmit CNS responses to the appropriate organs,
muscles, or glands. The transmission of both sensory (afferent) and motor (effer-
ent) information in the CNS is conducted by internuncial fibers.
There are 12 pairs of cranial nerves that originate in the brainstem with the
exception of 1 and 2, which arise from the diencephalon. Motor and sensory
sensations are supplied to the head, neck, and upper back except cranial nerve
number 10, the vagus nerve, which supplies the viscera. The cranial nerves are
described in Table 5–3.

TABLE 5–3 Cranial Nerves
Number Cranial Nerve What It Does
I Olfactory Smell Downloaded by [ Faculty of Nursing, Chiangmai University 5.62.158.117] at [07/18/16]. Copyright © McGraw-Hill Global Education Holdings, LLC. Not to be redistributed or modified in any way without permission.
II Optic Vision
III Oculomotor Pupillary constriction and accommodation,
elevation of upper eyelids, and extraocular
movements (EOMs)
IV Trochlear Downward, inward movement of the eye
V Trigeminal Muscles of chewing, opening jaw; tactile
sensations to the facial skin, cornea, oral, and
nasal mucosa; and eardrum tension
VI Abducens Lateral deviation of the eye
VII Facial Tears, salivation, taste sensation, facial
expressions, closing of eyes
VIII Acoustic/auditory Equilibrium and hearing
or vestibulocochlear
IX Glossopharyngeal Salivation, swallowing, speech, and gag reflex
X Vagus Laryngeal control of voluntary swallowing and
phonation. Involuntary activity of the heart,
lungs, and digestive tract
XI Spinal accessory Control of movements of the head and
shoulders or of the sternocleidomastoid and
trapezius muscles
XII Hypoglossal Tongue movements