Chapter 54 Care of the Patient with a Neurological Disorder - Complete Slides

1. Chapter 54 Care of the Patient with a Neurological Disorder - Complete Slides

2. Overview of Anatomy and Physiology • Nervous System • Responsible for communication and control within the body • Interprets and processes information received and sends in to the appropriate area of brain and spinal cord where response is generated • Body’s link to the environment • Works with endocrine to maintain homeostasis • NS reacts in a split second • Endocrine works more slowly to secrete hormones

3. Overview of Anatomy and Physiology • Structural divisions • 2 Main Structural division: • Central nervous system (CNS) • Brain and spinal cord • Occupies a medial position in the body • Responsible for interpreting incoming sensory information and issuing instructions based on past experiences

4. Overview of Anatomy and Physiology • 2 main structural divisions – cont’d • Peripheral nervous system (Lies Outside the CNS), divided into 2 main divisions: • Somatic nervous system • Sends messages from the CNS to the skeletal muscles • Voluntary muscles • Sensory (Afferent) and Motor (Efferent) Neuron • Autonomic nervous system • Transmits messages from the CNS to the smooth muscle, cardiac muscle and certain glands • Involuntary • Known as involuntary nervous system Actions takes place without conscious control • Sensory (Afferent) and Motor (Efferent) Neuron

5. Overview of Anatomy and Physiology -cells of the nervous system • Cells of the Nervous system • 2 Broad Category: • Neurons, transmitter cells as they carry messages to and from the brain and spinal cord. • Neuroglial or glial cells, support and protect the neurons while producing cerebrospinal fluid (CSF), which continuously bathes the structures of the CNS. • Neuron (nerve cell) • Basic nerve cell of nervous system • Separate unit compose of: • Cell body, the axon and the dendrites • Cell body • Contains a nucleus surrounded by cytoplasm • Axon • Cylindrical extension of a nerve cell • Conducts impulses away from the neuron cell body • Dendrites • Branching structures that extend from a cell body and receive impulses

6. Overview of Anatomy and Physiology -cells of the nervous system (cont’d) • Neuron (nerve cell) – cont’d • Synapse • A gap (space) between each neuron • Defined as region surrounding the point of contact between two neurons • Between a neuron and an effectors organ, across which nerve impulses are transmitted through the action of a neurotransmitter • Governed by “all or none” law • Never a partial transmission of a message • Impulse is either strong enough to elicit a response or too weak to generate the message

7. Overview of Anatomy and Physiology -cells of the nervous system (cont’d)

8. Overview of Anatomy and Physiology -cells of the nervous system (cont’d) • Neuromuscular junction • Area of contact between ends of a large myelinated nerve fiber and a fiber of skeletal muscle • Necessary for functioning of the body • Neurotransmitters act to make sure the neurological impulse passes from nerve to muscle

9. Overview of Anatomy and Physiology -cells of the nervous system (cont’d) • Neurotransmitters • It modify or result in transmission of impulses between synapses • Best known neurotransmitter are: Acetylcholine, Norepinephrine, dopamine and serotonin. • Acetylcholine (Ach) • Role in nerve impulse transmission • Spills into synapse area and speed transmission of impulse • Cholinesterase (enzyme) • Deactivate Ach once message or impulse has been sent • Happens rapidly and continuously as each impulse is relayed • Norepinephrine • Effects on maintaining arousal (awakening from deep sleep) and dreaming • Regulation of mood (i.e. happiness and sadness)

10. Overview of Anatomy and Physiology -cells of the nervous system (cont’d) • Neurotransmitters • Dopamine • Primarily affects motor function • Involved in gross subconscious movements of skeletal muscles • Role in emotional responses • In Parkinson’s disease • There is a decrease in dopamine, that’s why the person suffers from tremors or involuntary, trembling muscle movements • Serotonin • Induces sleep • Affects sensory perception • Controls temperature • Role in control of mood

11. Overview of Anatomy and Physiology -cells of the nervous system (cont’d) • Neuron coverings • Myelin • White, waxy, fatty material • Increases rate of transmission of impulses • Protects and insulate fibers • nodes of Ranvier • Wraps the axon leaving the CNS in layers of myelin with indentation • Further increase rate of transmission, because impulse can jump from node to node

12. Overview of Anatomy and Physiology -cells of the nervous system (cont’d) • Neuron coverings • Peripheral nervous system • Myelin is produced by Schwann cells • Outer membrane gives rise to another layer which is very important in regeneration of cells called neurilemma, functions of neurilemma: • Helps to regenerate injured axons • Regeneration of nerve cell occurs only in peripheral nervous system • Cells damaged in CNS results permanently (paralysis) • Do not have neurilemma, so no regeneration occurs.

13. Overview of Anatomy and Physiology -cells of the nervous system (cont’d)

14. Figure 54-1 (A, C, from Thibodeau, G.A., Patton, K.T. [2003]. Anatomy and physiology. [5th ed.]. St. Louis: Mosby. B, Courtesy of Brenda Russell, PhD, University of Illinois at Chicago.) A, Diagram of a typical neuron. B, Scanning electron micrograph of a neuron. C, Myelinated axon.

15. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Central Nervous System • One of two main divisions of nervous system • Composed of brain and spinal cord • Functions somewhat like a computer but is much more complex • Cranium protects the brain • Vertebral column protects the spinal cord

16. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brain • Specialized cells in the brain’s mass of convoluted, soft, gray or white tissue coordinate and regulate the functions of CNS • Largest organ weighing about 3 pounds • Divided into four parts • Cerebrum • Diencephalon • Cerebellum • Brain stem • Midbrain; pons; medulla oblongata; coverings of the brain and spinal cord; ventricles

17. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brain • Cerebrum • Largest part of the brain • Divided into left and right hemispheres • Outer portion is gray matter • Called - Cerebral cortex • Arrange into folds called gyri (convolutions) • Grooves are called sulci (fissures • Corpus callosum • Connecting structure or bridge • Divides two hemispheres into for lobes • Frontal lobe, parietal lobe, temporal lobe, occipital lobe

18. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brain • Cerebrum • Fissure is a natural division between the left and right hemispheres • Controls initiation of movement on opposite side of body • Specific areas of cerebral cortex are associated with specific functions: • Frontal Lobe • Written speech (ability to write) • Motor speech (ability to speak) • Motor ability – directs movements of body; left side controls the right side of the body and the right side of the brain controls the left side of the body. • Intellectualization – the ability to form concepts • Judgment formation

19. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brain.. cont • Cerebrum.. cont • Specific areas of cerebral cortex are associated with specific functions.. cont: • Parietal Lobe • Interpretation of sensory impulses from the skin such as touch, pain, and temperature • Recognition of body parts • Determination of left from right • Determination of shapes, sizes and distances • Temporal Lobe • Memory storage • Integration of auditory stimuli • Occipital Lobe • Interpretation of visual impulses from the retina • Understanding of the written word

20. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brain • Diencephalon • Called interbrain • It lies beneath the cerebrum • Contains: thalamus and hypothalamus • Thalamus • Relay station for some sensory impulses while interpreting other sensory messages (i.e. pain, touch, pressure) • Hypothalamus • Lies beneath the thalamus • Role in control of body temperature, fluid balance, appetite, emotions (i.e. fear, pleasure, pain) • Controls sympathetic and parasympathetic divisions of autonomic system as is the pituitary glands • Influences heartbeat, contraction and relaxation of walls of blood vessels, hormone secretion, and other vital body functions

21. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brain • Cerebellum • Lies posterior and inferior to cerebrum • Second largest portion of brain • Contains two hemispheres with convoluted surface much like cerebrum • Responsible for coordination of voluntary movement and maintenance of balance, equilibrium, and muscle tone • Sensory messages from semicircular canals in inner ear sends messages to cerebellum • Brain stem • Located at the base of the brain • Consist of: Midbrain; pons; medulla oblongata; • Connect spinal cord and cerebrum • Carries all nerve fibers between spinal cord and cerebrum

22. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brainstem..cont • Midbrain • Superior portion of brain stem • Responsible for motor movement, relay of impulses, auditory and visual reflexes • Origin of Cranial Nerves (CN) III and IV • Pons • Connects midbrain to medulla oblongata • “Pons” means “bridge” • Origin of CN V through VIII • Composed of myelinated nerve fibers and is responsible for sending impulses to structures that are inferior and superior to it • Contains a respiratory center that compliments respiratory centers located in medulla

23. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Brainstem.. cont • Medulla oblongata • Distal portion of brainstem • Origin of CN IX and XII • Controls heart beat, rhythm of breathing, swallowing, coughing, sneezing, vomiting, and hiccups (singultus) • Vasomotor center regulates diameter of blood vessels, helps aid in BP control

24. Figure 54-2 (From Thibodeau, G.A., Patton, K.T. [1987]. Anatomy and physiology. St. Louis: Mosby.) Sagittal section of the brain (note position of midbrain).

25. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Coverings of brain and spinal cord • Three protective coverings called meninges • 1. Dura mater • Outer most layer • 2. Arachnoid membrane • Second layer • 3. Pia mater • Inner most layer • Provides oxygen and nourishment to nervous tissue • These layers also bathe Spinal Cord and brain in cerebrospinal fluid (CSF)

26. Overview of Anatomy and Physiology -Central Nervous System (CNS)

27. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Ventricles • Four in all: 3rd, 4th, left and right lateral ventricle • Spaces or cavities located in brain • CSF • Clear and resembles plasma • Flows into subarachnoid spaces around brain and spinal cord and cushions them • Contains protein, glucose, urea, and salts • Contains substances that forms a protective barrier (the Blood-Brain Barrier) • Prevents harmful substances to enter the Brain and SC

28. Overview of Anatomy and Physiology -Central Nervous System (CNS)

29. Overview of Anatomy and Physiology -Central Nervous System (CNS)

30. Overview of Anatomy and Physiology -Central Nervous System (CNS) • Spinal Cord • 17 to 18 inch cord extending from brainstem to second lumbar vertebra • Two main functions: • Conducting impulses to and from the brain • Serving as a center for reflex actions • Responsible for certain reflex activity such as knee jerk • Sensory neuron sends information to cord, a central neuron (within the cord) interprets impulse, and a motorneuron sends message back to muscle or organ involved • Message is sent, interpreted, and acted upon without traveling to brain

31. Figure 54-3 (From Thibodeau, G. A., Patton, K. T. [1990]. Anthony’s textbook of anatomy and physiology. [13th ed.]. St. Louis: Mosby.) Neural pathway involved in the patellar reflex.

32. Another example

33. Overview of Anatomy and Physiology - Peripheral nervous system • Peripheral nervous system • Comprise motor nerves, sensory nerves, and ganglia outside brain and SC • 31 pairs of spinal nerves • 12 pairs of cranial nerves • Autonomic nervous system • Sympathetic nervous system • Parasympathetic nervous system

34. Overview of Anatomy and Physiology - Peripheral nervous system • Spinal Nerves • 31 pairs and all are mixed nerves • Transmit sensory information to SC through afferent neurons and motor information from CNS to areas of body through efferent neurons • Named according to the corresponding vertebra (e.g C1, C2) • See next figure

35. Overview of Anatomy and Physiology - Peripheral nervous system

36. Overview of Anatomy and Physiology - Peripheral nervous system • Cranial Nerves • 12 pairs • Attach to posterior surface of brain, mainly brainstem • Conduct impulses between head, neck, and brain, excluding vagus nerve (CN X), which also serves organs in thoracic and abdominal cavities • List of CN, impulses sent and functions: • CN I, Olfactory – nose to brain – sense of smell • CN II, Optic – eye to brain – vision • CN III, Oculomotor – brain to eye muscles – eye movements, pupillary control • CN IV, Trochlear – brain to external eye muscles – eye movements • CN V, Trigeminal (opthalmic, maxillary, mandibular branch) – skin & mucus membrane of head to brain; teeth to brain; brain to chewing muscles – sensation of face, scalp and teeth; chewing movements • CN VI, Abducens – brain to external eye muscles – turning eyes outward • CN VII, Facial – taste buds of tongue to brain; brain to facial muscles – sense of taste; contraction of muscles of facial expression • CN VIII, Acoustic (vestibulocochlear) – ear to brain – hearing; sense of balance

37. Overview of Anatomy and Physiology - Peripheral nervous system • Cranial Nerves.. cont • List of CN, impulses sent and functions..cont: • CN IX, Glossopharyngeal – throat and taste buds of tongue to brain; brain to throat muscle and salivary glands – sensations of throat, taste, swallowing, movements, secretion of saliva • CN X, Vagus – throat, larynx & organs in thoracic & abdominal cavities to brain; brain to muscles of throat & to organs in thoracic & abdominal cavities – sensation of throat, larynx & of thoracic & abdominal organs; swallowing, voice production, slowing heartbeat, acceleration of peristalsis • CN XI, Spinal accessory – brain to certain shoulder & neck muscles – shoulder movements & turning movements of head • CN XII, Hypoglossal – brain to muscles of tongue – tongue movements

38. Overview of Anatomy and Physiology - Peripheral nervous system

39. Overview of Anatomy and Physiology - Peripheral nervous system • Autonomic Nervous System • Controls activities of smooth muscle, cardiac muscle, and all glands • Subdivision of peripheral nervous system • Primary function is to maintain internal homeostasis • Strives to maintain a normal heartbeat, constant body temperature, and normal respiratory pattern • Two divisions: • Sympathetic nervous system • Parasympathetic nervous system

40. Overview of Anatomy and Physiology - Peripheral nervous system • Autonomic Nervous System • Two divisions • Antagonistic • One slows an action, and the other accelerates the action • Note: function simultaneously, but have the ability to dominate each other as the need arises • Stress • Sympathetic takes over to prepare body for “fight or flight” • Heartbeat accelerates, BP increases, adrenal glands increase secretions • To calm the body • Parasympathetic dominates • Slowing heartbeat and decreasing BP and adrenal hormones

41. Overview of Anatomy and Physiology - Peripheral nervous system

42. Overview of Anatomy and Physiology • Effects of Normal Aging on the Nervous System • Loss of brain weight • Loss of neurons (1% a year after age 50) • Cortex losing cells faster than the brainstem • Remaining cells undergo structural changes • General decline in interconnections of dendrites • Reduction in cerebral blood flow • Decrease in brain metabolism and oxygen utilization • Neurons may contain senile plaques, neurofibrillary tangles & age pigment lifofuscin • Altered sleep/ wakefulness ratio • Decrease in ability to regulate body temperature • Decrease in velocity of nerve impulses • Decreased blood supply to spinal cord causes decreased reflexes

43. Overview of Anatomy and PhysiologyOlder Adult Consideration Box • Neurological Disorder • As neuron are lost with aging, there is a deterioration in neurological function, resulting in slowed reflex and reaction time • Tremors that increase with fatigue are commonly observed in adults • The sense of touch & the ability for fine motor coordination diminish with aging • Most older people possess the ability to learn, but the speed of learning is slowed. Short-term memory is more affected by aging than long-term memory • The incidence of physiologic dementia or organic brain syndrome-including Alzheimer’s disease, Pick’s disease & multiinfarct dementia-increases with aging • Incidence of stroke increases with age. Prognosis is affected by the location & extent of the cerebral damage. Rehab potential after a stroke is often reduced by advanced age & coexisting medical problem • Nerve irritation resulting from arthritis, joint injuries or spinal-cord compression can cause chronic pain or weakness • Dementia is not a normal consequence of aging but may be result of may reversible conditions, including anemia, fluid & electrolyte imbalance, malnutrition, hypothyroidism, metabolic disturbances, drug toxicity, a drug reaction/idiosyncrasy & hypotension.

44. Overview of Anatomy and Physiology • Prevention of neurological problems • Avoid drug and alcohol use • Smoking increases lung cancer and lung CA metastasizes to the brain • Safe use of motor vehicles • Safe swimming practices • Safe handling and storage of firearms • Use of hardhats in dangerous construction areas • Use of protective padding as needed for sports

45. Assessment of the Neurological System • History • Essential for diagnosing neurological disease • Includes specifics about symptoms experienced • Asses patient understanding & perception of what is happening. • Obtain info from family members/ significant others may be helpful • Make sure information is complete • For patients with suspected neurological conditions presence of many symptoms of subjective data may be significant. These include the following: • Headaches, especially those that first occur after middle age or those that change in character; headaches that are worse in the morning or awaken a person from sleep are especially significant

46. Assessment of the Neurological System • History..cont • For patients with suspected neurological conditions presence of many symptoms of subjective data may be significant. These include the following..cont: • Clumsiness or loss of function in an extremity • Change in visual acuity • Any new or worsened seizure activity • Numbness or tingling in one or more extremities • Pain in an extremity or other part of the body • Personality changes or mood swings • Extreme fatigue or tiredness

47. Assessment of the Neurological System • Mental Status • Assessment of patient neurological mental status is important • Examination generaly includes orientation (person, place, time, and purpose), mood and behavior, general knowledge (such as names of U.S. presidents), and short- and long-term memory. • The patient’s attention span and ability to concentrate may also be assessed • Note actual patient statement & note actual level of orientation (name, date, time & purpose), always try different approach cause patient my learn the correct answer through repetition

48. Assessment of the Neurological System • Level of consciousness • Level of consciousness (LOC) is the earliest and most sensitive indicator that something is changing. • A decreasing level of consciousness is the earliest sign of increased intracranial pressure. • LOC has two components • Arousal (or wakefulness) and • Awareness. • Wakefulness is the most fundamental part of LOC. If the patient can open the eyes spontaneously to voice or to pain, it says that the wakefulness center in the brainstem is still functioning. • Awareness, a higher function controlled by the reticular activating system in the brainstem.

49. Assessment of the Neurological System • Level of consciousness • Awareness has four components: • Orientation: person, place, time, purpose • Memory: assess short-term memory; do not ask yes or no questions. • Calculation: example, “If you have $2 and your apple costs $1.25, how many quarters would you get back?” • Fund of knowledge: Ask the patient to name the president and to tell you what’s on the national news (Lower, 2002). • Restlessness, disorientation, and lethargy may be seen first.

50. Assessment of the Neurological System • LEVELS OF CONSCIOUSNESS • Alert, Disorientation, Stupor, Semicomatose, Comatose, level & description below: • Alert: Responds appropriately to auditory, tactile, and visual stimuli • Disorientation: Disoriented; unable to follow simple commands, thinking slowed, inattentive, flat affect. • Stupor: Responds to verbal commands with moaning or groaning, if at all • Semicomatose: Impaired state of consciousness characterized by obtundation and stupor, from which a patient can be aroused only by energetic stimulation • Comatose: Unable to respond to painful stimuli; cornea and papillary reflexes are absent. The patient cannot swallow or cough. The patient is incontinent of urine and feces. The EEG pattern demonstrates decreased or absent neuronal activity.