IT 1 NE LOGICAL N
ASSESSMENT
Structure
1.0 Objectives
1.1 Introduction
1.2 Review of Anatomy and Physiology
1;3 Cormnon Neurological Diagnostic Measures and Nursing Implications
1.4 Neulrological Nursing Assessment
1.5 Common Manifestations of Neurological Disorders
1.5.1 Increased Intracranial Pressure (Intracranial I-Iyperlension)
1.5.2 Altered Selisoriul~l
1.5.3 Paralysis
1.5.4 Convulsions
1.5.5 Hyperther~iiia
1 S.6 Aphasia
1.5.7 Sy~lcope
1.6 Let Us Suin Up
1 . 7 . Keywords '
1.8 Answers to Check Your Progress
1.9 Further Readings
1.0 OBJECTIVES
After completing this unit, you should be able to:
* explain the related anatomy and physiology of nervous systeni;
describe the various diagnostic measures and nursing implications;
a explain how the comlnon ~~elnrological
problems occur;
discuss the methods of assessing the patients with neurological problems;
0 state how you would do the basic neurological examination; and
0 describe the nursing measures to solve specific neurological problems.
1.1 INTRODUCTION
The nervous system is the body's .most highly organized system. Ne~~rological
nursing is an area of practice i.e. highly demanding and rewarding for nurses.
You will be able to understand the neurological problems and the method of
neurological examination only if you have a sound basic knowledge of the
anatomy and physiology of the nervous system, 111 this Unit, you will review the
anatomy and physiology of the nervolfs system before you read hrther. .
After reviewing the anatomy and physiology3 you will easily understand the
common problems experienced by patients and the m@thodof neurological
, I
I
Neurological Nursing and examination. Many disorders of the nervous system are chronic conditions I
Care of Elderly resulting in impaired function and long-term disability. The increasing ability and I
concern for the patient as a person, you can try to ease many of the problems I
experienced by these patients optimistically.
Further in this Unit, you are going to learn about the common diagnostic
measures and nursing implications, problems of patients with diseases in the
nervous system and the nursing measures to solve these problems. You will also
Iearil about the neurological il~~rsing
assessment in a patient in detail.
1.2 REVIEW OF ANATOMY AND PHYSIOLOGY I
Neuron
Basic struch~raland functional unit of the nervous system. It consists of cell
I
body, with two extensions, the dentrites that receive information from axon
terminals at special sites called synopses, and axons, whicll transinit information
away from the cell body to adjacent neurons. The cell membrane encloses the
outer boundary of the cell body, dendrite, and axon. One centrally located
nucleus is typically found in each neuron. See the detail structure in Fig. 1. I .
,The neurons can be unipolar, bipolar or multipolar. They can be large and having Neurological Nursing
long axons (Golgi type I neuron) or can be with smaller cells with shol-t axons Assesslnent
that branch repeatedly (Golgi type 11). Functionally, they can be affcrent
(sensory), internuncial that assist in impulse conduction or efferent (motor)
neuroi~s.
The neurons are grouped in chains in the peripheral nervous systeln to form
nerves. These collections of neurons are connected in cotnplex ways. The
connection determines what each collection of neurons is capable of doing. The
neurons are organized into circuits, some of which are simple and made up of
relatively few neurons and others are complicated. A single t'leuron may be a part
of several different ne~irolb~iccircuits and this may have a role in different
functions. Many of the futzctional properties of the neuron lie within the cell
membrane. The nlelnbrane is permeable to oxygen, carbon dioxide and certain
inorganic ions and impern~eableto protein and other inorganic ions-the
differential permeability character.
The neuron systenl function occurs fionz the phenomenon of action potential.
The two phases of action potential are depolarization (positive state) and
repolarisation (return to llosn~alresting potential). When resting, tlze nerve fiber
is charged with the insidc of tlze cell inelnbrane negatively charged in relation to
the outside. A high concentration of sodiun~exists extraccllt~larlyand a high
concentration of potassium exists iatracellulnrly. When tlie nerve fiber is
stimulated, there is an influx of sodium and a loss of intracellular potassiu~llby
diffusion. The cell becomes positive and tl~eaction potential (depolarization)
occurs. After depolarization, the ion llow is reversed and the mcmbrane is
retunled to resting state. The time interval between the depolarization and part of
the repolarisation is called the absolute ref'ractory period. During this time, thc
nerve cannot be re-slin~ulated.This prevents repetitive excilation of the neive.
The velocity of the action potential is related to the size of the axon and whetller
myelin is present. Myelin is ail excellent insulator of axons, by preventing
almost all ion flow across the axon and ils mernbrmle. At the nodes of Ranvier-
the uninsulated area, ions can flow easily between the extrn cellular fluid and
axon. The fibers with n~yelinare called large fibers which appear white in colo~ir
e.g. white matter of the nervous system. The iibers withoul myelin a x called
small fibers.
Synapse '.
A synapse is the structural and fL11lctionaljunction between two neurons, It is the
point at wllicll the nerve impulse is transmitted from one neuron to another or ,
from neuron to efferent organ. The essential structures of synaptic trans~nission
are a pre-synaptic terminal, a synaptic cleft, and a receptor site on the post-
synaptic cell. When a nerve impulse reacl~esthe end of axan, ii causcs release of *
neurotranslnittcr from tiny vesicles within the axon tesnlinal. Tl-re
neurotransmitter then crosses the nlicroscopic space between the two ileurons
and attaches to the receptor sites of the receiving neuron. This causes change in
the permeability of the postsynaptic cell membrane to specific ions such as Na
and K and change in the electrical potential of lhe membrane. Neurotransmitters
may be excitatory e,g, acetylcholine, norepinephrine, serotonin, dapamine,
glutamale and histamine or may be inllibito~ye.g. glycine and gamma-
aminobutyric.
The ~ e i v o u sSystem
The nervous system has two major divisions. The central netvous systenz (CNS)
and the peripheral nervous system, The CNS is made up of a collection of
7
, Neurological Nursing and neurons and their connections into the brain and spinal cord. The brain is housed
Care of Elderly in the cranium made up of eight bones (Fig.l.2). The brain consists of the
cerebrum, the brain stem and the cerebellum.
Frontal bone Orbital part of
/------ frontal bone
Groove for superior
sagittal sinus
- \----------Occipital bone
Fig. 1.2: Interior of base of #hull, superior views
Cerebrum is longitudinally divided into the right and left hemispheres, each
consisting of the fmntal; parietal, temporal and occipital lobes. This is the
largest part of the brain and is covered on the outside by the cerebral cortex
which contains more than 14 billion neurons. It receives and analyses all
impulses, controls voluntary movement and stores knowledge of impulses
received. Deep within the cerebrum are the masses of grqy matter (cell bodies) i
8 called the basal ganglia which function as part of the extraphyramidal system I
ASSESSMENT
Structure
1.0 Objectives
1.1 Introduction
1.2 Review of Anatomy and Physiology
1;3 Cormnon Neurological Diagnostic Measures and Nursing Implications
1.4 Neulrological Nursing Assessment
1.5 Common Manifestations of Neurological Disorders
1.5.1 Increased Intracranial Pressure (Intracranial I-Iyperlension)
1.5.2 Altered Selisoriul~l
1.5.3 Paralysis
1.5.4 Convulsions
1.5.5 Hyperther~iiia
1 S.6 Aphasia
1.5.7 Sy~lcope
1.6 Let Us Suin Up
1 . 7 . Keywords '
1.8 Answers to Check Your Progress
1.9 Further Readings
1.0 OBJECTIVES
After completing this unit, you should be able to:
* explain the related anatomy and physiology of nervous systeni;
describe the various diagnostic measures and nursing implications;
a explain how the comlnon ~~elnrological
problems occur;
discuss the methods of assessing the patients with neurological problems;
0 state how you would do the basic neurological examination; and
0 describe the nursing measures to solve specific neurological problems.
1.1 INTRODUCTION
The nervous system is the body's .most highly organized system. Ne~~rological
nursing is an area of practice i.e. highly demanding and rewarding for nurses.
You will be able to understand the neurological problems and the method of
neurological examination only if you have a sound basic knowledge of the
anatomy and physiology of the nervous system, 111 this Unit, you will review the
anatomy and physiology of the nervolfs system before you read hrther. .
After reviewing the anatomy and physiology3 you will easily understand the
common problems experienced by patients and the m@thodof neurological
, I
I
Neurological Nursing and examination. Many disorders of the nervous system are chronic conditions I
Care of Elderly resulting in impaired function and long-term disability. The increasing ability and I
concern for the patient as a person, you can try to ease many of the problems I
experienced by these patients optimistically.
Further in this Unit, you are going to learn about the common diagnostic
measures and nursing implications, problems of patients with diseases in the
nervous system and the nursing measures to solve these problems. You will also
Iearil about the neurological il~~rsing
assessment in a patient in detail.
1.2 REVIEW OF ANATOMY AND PHYSIOLOGY I
Neuron
Basic struch~raland functional unit of the nervous system. It consists of cell
I
body, with two extensions, the dentrites that receive information from axon
terminals at special sites called synopses, and axons, whicll transinit information
away from the cell body to adjacent neurons. The cell membrane encloses the
outer boundary of the cell body, dendrite, and axon. One centrally located
nucleus is typically found in each neuron. See the detail structure in Fig. 1. I .
,The neurons can be unipolar, bipolar or multipolar. They can be large and having Neurological Nursing
long axons (Golgi type I neuron) or can be with smaller cells with shol-t axons Assesslnent
that branch repeatedly (Golgi type 11). Functionally, they can be affcrent
(sensory), internuncial that assist in impulse conduction or efferent (motor)
neuroi~s.
The neurons are grouped in chains in the peripheral nervous systeln to form
nerves. These collections of neurons are connected in cotnplex ways. The
connection determines what each collection of neurons is capable of doing. The
neurons are organized into circuits, some of which are simple and made up of
relatively few neurons and others are complicated. A single t'leuron may be a part
of several different ne~irolb~iccircuits and this may have a role in different
functions. Many of the futzctional properties of the neuron lie within the cell
membrane. The nlelnbrane is permeable to oxygen, carbon dioxide and certain
inorganic ions and impern~eableto protein and other inorganic ions-the
differential permeability character.
The neuron systenl function occurs fionz the phenomenon of action potential.
The two phases of action potential are depolarization (positive state) and
repolarisation (return to llosn~alresting potential). When resting, tlze nerve fiber
is charged with the insidc of tlze cell inelnbrane negatively charged in relation to
the outside. A high concentration of sodiun~exists extraccllt~larlyand a high
concentration of potassium exists iatracellulnrly. When tlie nerve fiber is
stimulated, there is an influx of sodium and a loss of intracellular potassiu~llby
diffusion. The cell becomes positive and tl~eaction potential (depolarization)
occurs. After depolarization, the ion llow is reversed and the mcmbrane is
retunled to resting state. The time interval between the depolarization and part of
the repolarisation is called the absolute ref'ractory period. During this time, thc
nerve cannot be re-slin~ulated.This prevents repetitive excilation of the neive.
The velocity of the action potential is related to the size of the axon and whetller
myelin is present. Myelin is ail excellent insulator of axons, by preventing
almost all ion flow across the axon and ils mernbrmle. At the nodes of Ranvier-
the uninsulated area, ions can flow easily between the extrn cellular fluid and
axon. The fibers with n~yelinare called large fibers which appear white in colo~ir
e.g. white matter of the nervous system. The iibers withoul myelin a x called
small fibers.
Synapse '.
A synapse is the structural and fL11lctionaljunction between two neurons, It is the
point at wllicll the nerve impulse is transmitted from one neuron to another or ,
from neuron to efferent organ. The essential structures of synaptic trans~nission
are a pre-synaptic terminal, a synaptic cleft, and a receptor site on the post-
synaptic cell. When a nerve impulse reacl~esthe end of axan, ii causcs release of *
neurotranslnittcr from tiny vesicles within the axon tesnlinal. Tl-re
neurotransmitter then crosses the nlicroscopic space between the two ileurons
and attaches to the receptor sites of the receiving neuron. This causes change in
the permeability of the postsynaptic cell membrane to specific ions such as Na
and K and change in the electrical potential of lhe membrane. Neurotransmitters
may be excitatory e,g, acetylcholine, norepinephrine, serotonin, dapamine,
glutamale and histamine or may be inllibito~ye.g. glycine and gamma-
aminobutyric.
The ~ e i v o u sSystem
The nervous system has two major divisions. The central netvous systenz (CNS)
and the peripheral nervous system, The CNS is made up of a collection of
7
, Neurological Nursing and neurons and their connections into the brain and spinal cord. The brain is housed
Care of Elderly in the cranium made up of eight bones (Fig.l.2). The brain consists of the
cerebrum, the brain stem and the cerebellum.
Frontal bone Orbital part of
/------ frontal bone
Groove for superior
sagittal sinus
- \----------Occipital bone
Fig. 1.2: Interior of base of #hull, superior views
Cerebrum is longitudinally divided into the right and left hemispheres, each
consisting of the fmntal; parietal, temporal and occipital lobes. This is the
largest part of the brain and is covered on the outside by the cerebral cortex
which contains more than 14 billion neurons. It receives and analyses all
impulses, controls voluntary movement and stores knowledge of impulses
received. Deep within the cerebrum are the masses of grqy matter (cell bodies) i
8 called the basal ganglia which function as part of the extraphyramidal system I
