Introduction to Neurologic System - Al-Balqa University

Al-Balqa Applied University Faculty of Nursing Department of Nursing Academic Year 2024/2025-2nd Semester Adult Health Nursing 2- Theoretical- NUR 222 14. Introduction to Neurologic System Course Instructors: Dr. Saleh Al Omar Dr. Falast...

Al-Balqa Applied University Faculty of Nursing Department of Nursing Academic Year 2024/2025-2nd Semester Adult Health Nursing 2- Theoretical- NUR 222 14. Introduction to Neurologic System Course Instructors: Dr. Saleh Al Omar Dr. Falastine Hamdan 1  Outlines Anatomy Physiology Assessment of the Nervous System: Health history Assessment of the Nervous System: Physical examination Diagnostic tests and procedures 2/22/2025 2  Anatomy The nervous system consists of two major parts: 1. The central nervous system (CNS): Brain Spinal cord 2. The peripheral nervous system: Cranial nerves Spinal nerves Autonomic nervous system 2/22/2025 3  Anatomy The basic functional unit of the brain is the neuron Neurotransmitters communicate messages from one neuron to another or from a neuron to a target cell, such as muscle or endocrine cells. All brain functions are modulated through neurotransmitter receptor site activity. Major Neurotransmitters: Acetylcholine (major transmitter of the parasympathetic nervous system, usually excitatory), Norepinephrine (major transmitter of the sympathetic nervous system, usually excitatory). 2/22/2025 4  The Central Nervous System: The Brain The brain is divided into three major areas: The cerebrum The brainstem The cerebellum The cerebrum is composed of : Two hemispheres The thalamus The hypothalamus The basal ganglia The brainstem includes: The midbrain 2/22/2025 5 Pons 2/22/2025 6  Structures Protecting the Brain 2/22/2025 7  Cerebrospinal Fluid (CSF) CSF is a clear and colorless fluid that is produced in the choroid plexus of the ventricles and circulates around the surface of the brain and the spinal cord. Blockage of the flow of CSF anywhere in the ventricular system produces obstructive hydrocephalus. CSF is important in immune and metabolic functions in the brain. It is produced at a rate of about 500 mL/day. The composition of CSF is similar to other extracellular fluids (such as blood plasma), but the concentrations of the various constituents differ. 2/22/2025 8 2/22/2025 9  Cerebral Circulation 2/22/2025 10  Blood–Brain Barrier The CNS is inaccessible to many substances that circulate in the blood plasma because of the blood–brain barrier. This barrier is formed by the endothelial cells of the brain’s capillaries, which form continuous tight junctions, creating a barrier to macromolecules and many compounds. The blood–brain barrier has a protective function but can be altered by trauma, cerebral edema, and cerebral hypoxemia 2/22/2025 11  The Spinal Cord Is continuous with the medulla, extending from the cerebral hemispheres and serving as the connection between the brain and the periphery. it extends from the foramen magnum at the base of the skull to the lower border of the first lumbar vertebra, where it tapers to a fibrous band called the conus medullaris. Continuing below the second lumbar space are the nerve roots that extend beyond the conus, which are called the cauda equina because they resemble a horse’s tail. Meninges 2/22/2025 surround the spinal cord. 12 2/22/2025 13  The Spinal Cord 2/22/2025 14 2/22/2025 15 The Peripheral Nervous System: Cranial Nerves 12 pairs of cranial nerves emerge from the lower surface of the brain and pass through openings in the base of the skull. Three cranial nerves are entirely sensory (I, II, VIII), five are motor (III, IV, VI, XI, and XII), and four are mixed sensory and motor (V, VII, IX, and X). The cranial nerves are numbered in the order in which they arise from the brain. The cranial nerves innervate the head, neck, and special sense structures. 2/22/2025 16 2/22/2025 17 The Peripheral Nervous System: Spinal Nerves The spinal cord is composed of 31 pairs of spinal nerves: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each spinal nerve has a ventral root and a dorsal root. The dorsal roots are sensory and transmit sensory impulses from specific areas of the body known as dermatomes to the dorsal horn ganglia. The ventral roots are motor and transmit impulses from the spinal cord to the body. 2/22/2025 18 2/22/2025 19 2/22/2025 20 2/22/2025 21  Autonomic Nervous System The autonomic nervous system regulates the activities of internal organs such as the heart, lungs, blood vessels, digestive organs, and glands. There are two major divisions: The sympathetic nervous system: predominantly excitatory responses (i.e., the “fight-or-flight” response) The main sympathetic neurotransmitter are epinephrine and norepinephrine The parasympathetic nervous system: controls mostly visceral functions. 2/22/2025 22 the primary neurotransmitter is acetylcholine.  Physiology Functions of the nervous system: Control motor, sensory, autonomic, cognitive, and behavioral activities. Monitor the body’s processes. Respond to the internal and external environment. Maintain homeostasis. Direct all psychological, biologic, and physical activity through 2/22/2025 23 complex chemical and electrical messages.  Assessment of the Nervous System: Health History Common Symptoms Pain Seizures Dizziness and Vertigo Visual Disturbances Muscle Weakness Abnormal Sensation 2/22/2025 24  Physical Assessment Assessing Consciousness and Cognition Examining the Cranial Nerves Examining the Motor System Examining the Sensory System Balance and Coordination Examining the Reflexes 2/22/2025 25  Assessing Consciousness and Cognition Mental Status Intellectual Function Thought Content Emotional Status Language Ability Impact on Lifestyle Level of Consciousness 2/22/2025 26  Level of Consciousness Consciousness is the patient’s wakefulness and ability to respond to the environment. To assess level of consciousness: Observe for alertness and ability to follow commands. If the patient is not alert or able to follow commands, observe for eye opening; verbal response and motor response to stimuli, if any; and the type of stimuli needed to obtain a response. 2/22/2025 27  Level of Consciousness 2/22/2025 28  Examining the Cranial Nerves Cranial nerves are assessed when: level of consciousness is decreased, with brain stem pathology, in the presence of peripheral nervous system disease. Right and left cranial nerve functions are compared throughout the examination 2/22/2025 29  Examining the Motor System Motor Ability: an assessment of muscle size and tone as well as strength, coordination, and balance. Muscle Strength: Assessing the patient’s ability to flex or extend the extremities against resistance tests muscle strength. Use a 5-point scale to rate muscle strength. A 5 indicates normal muscle strength; 4 indicates slight weakness; 3 indicates moderate weakness; 2 indicates severe weakness; 1 indicates very severe 2/22/2025 30 weakness; and 0 indicates no movement.  Examining the Sensory System Assessment of the sensory system involves tests for: Tactile sensation Superficial pain Temperature Vibration Position sense (proprioception). Sensory deficits resulting from peripheral neuropathy or spinal cord injury follow anatomic dermatomes. 2/22/2025 31  Balance and Coordination Cerebellar and basal ganglia influence on the motor system is reflected in balance control and coordination Coordination in the hands and upper extremities is tested by having the patient perform rapid, alternating movements and point-to-point testing. Coordination in the lower extremities is tested by having the patient run the heel down the anterior surface of the tibia of the other leg. Ataxia is an incoordination of voluntary muscle action, particularly of the muscle groups used in activities such as walking or reaching for 2/22/2025 32 objects.  Examining the Reflexes Reflexes are involuntary contractions of muscles or muscle groups in response to a stimulus. Reflexes are classified as Deep Tendon Reflexes Superficial Reflexes Pathologic Reflexes Deep Tendon Reflexes include examining: Biceps Reflex, Triceps Reflex, Brachioradialis Reflex, Patellar Reflex, Achilles Reflex, & Clonus. Deep tendon reflex responses are often graded on a scale of 0 to 4+, with 2+ considered 2/22/2025 normal. 33 Some examiners prefer to use the terms present, absent, and diminished when  Diagnostic Evaluation: CT SCAN CT SCAN images distinguishing differences in tissue densities of the skull, cortex, subcortical structures, and ventricles. IV contrast agent may be used to highlight differences further. Usually performed first without contrast material and then with IV contrast, if needed. Abnormalities detected on brain CT include tumor or other masses, infarction, hemorrhage, displacement of the ventricles, and cortical atrophy. CT angiography allows visualization of blood vessels; in some situations, this eliminates the need for formal angiography. 2/22/2025 34 2/22/2025 35  Diagnostic Evaluation: MRI MRI uses a powerful magnetic field to obtain images of different areas of the body. An MRI scan can be performed with or without a contrast agent and Can identify a cerebral abnormality earlier and more clearly than other diagnostic tests. It is particularly useful in the diagnosis of brain tumor, stroke, and multiple sclerosis. 2/22/2025 36 2/22/2025 37  Diagnostic Evaluation: PET Positron Emission Tomography is a computer-based nuclear imaging technique The patient either inhales a radioactive gas, or is injected with a radioactive substance. PET permits the measurement of blood flow, tissue composition, and brain metabolism and thus indirectly evaluates brain function. PET is useful in showing metabolic changes in the brain (Alzheimer’s disease), locating lesions (brain tumor, epileptogenic lesions), identifying blood flow and oxygen, metabolism in patients with strokes, distinguishing tumor from areas of necrosis, and revealing biochemical abnormalities associated with mental illness. 2/22/2025 38 2/22/2025 39  Diagnostic Evaluation: Cerebral Angiography An x-ray study of the cerebral circulation with a contrast agent injected into a selected artery. Used to determine vessel patency, identify presence of collateral circulation, and provide detail on vascular anomalies that can be used in planning interventions. Prior to the angiography, the patient’s BUN and Cr should be checked. The patient should be well hydrated. When the femoral artery is selected for access, the hair in the groin is clipped and prepared and a local anesthetic agent is given. 2/22/2025 40 Neurologic assessment is conducted during and immediately following 2/22/2025 41  Diagnostic Evaluation: Cerebral Angiography Nursing care after cerebral angiography includes: Observation of the injection site for bleeding or hematoma formation. The color and temperature of the involved extremity are assessed to detect possible embolism. Fluids are encouraged to facilitate clearance of the contrast through the kidney. Monitoring for an allergic reaction to the contrast agent, as well as hypotension if vasodilatory medications were used to facilitate a radial approach. 2/22/2025 42  Diagnostic Evaluation: Electroencephalography EEG provides an assessment of cerebral electrical activity. The standard EEG takes 45 to 60 minutes It is useful for diagnosing and evaluating seizure disorders, coma, or organic brain syndrome. Tumors, brain abscesses, blood clots, and infection may cause abnormal patterns in electrical activity. The EEG is also used in making a determination of brain death. Anticonvulsant agents, tranquilizers, stimulants, and depressants should be withheld 24 to 48 hours before an EEG, because these medications can alter the EEG wave patterns or mask the abnormal wave patterns of seizure disorders 2/22/2025 43 Coffee, tea, chocolate, and cola drinks are omitted from the meal before the 2/22/2025 44  Diagnostic Evaluation: LP and Examination of CSF A lumbar puncture (spinal tap) is carried out by inserting a needle into the lumbar subarachnoid space to withdraw CSF. The needle is inserted into the subarachnoid space in the widest intervertebral spaces; between the second and third, the third and fourth, or fourth and fifth lumbar vertebrae. The test may be performed to: Obtain CSF for examination. Measure and reduce CSF pressure. Determine the presence or absence of blood in the CSF. Administer medications intrathecally (into the spinal canal). 2/22/2025 45 2/22/2025 46 2/22/2025 47 2/22/2025 48 2/22/2025 49  Diagnostic Evaluation: LP and Examination of CSF The CSF should be clear and colorless. Pink, blood-tinged, or grossly bloody CSF may indicate a subarachnoid hemorrhage. The CSF may be bloody initially because of local trauma but becomes clearer as more fluid is drained Specimens are obtained for cell count, culture, glucose, protein, and other tests as indicated. The specimens should be sent to the inhibitor laboratory immediately because changes will take place and alter the result if the specimens are 2/22/2025 50 allowed to stand. 2/22/2025 51 2/22/2025 52  Diagnostic Evaluation: LP and Examination of CSF Complications: Post–Lumbar Puncture Headache: ranging from mild to severe, may occur a few hours to several days after the procedure. The headache is caused by CSF leakage at the puncture site Post–lumbar puncture headache may be avoided if a small-gauge needle (22 gauge) is used. A post–lumbar puncture headache is usually managed with analgesic agents, encouraging hydration, ingestion of caffeine, and lying supine 2/22/2025 53  Diagnostic Evaluation: LP and Examination of CSF Other complications: Herniation of the intracranial contents Spinal epidural abscess Spinal epidural hematoma Meningitis Temporary voiding problems Slight elevation of temperature Backache or spasms 2/22/2025 54 Stiffness of the neck.  Thank You ANY QUESTION?? 2/22/2025 55 References Brunner & Suddarth’s Textbook of Medical-Surgical Nursing. 2022. 15th edition. Wolters Klower. USA. Lynn, P. 2022. Taylor’s Clinical Nursing Skills: A Nursing Process Approach. 6th ed. Wolters Kluwer. USA Perry, A. G., Potter, P. A., & Ostendorf, W. (2020). Nursing Interventions & Clinical Skills, 8th ed. Elsevier Health Sciences Clinical Handbook for Brunner & Suddarth's Textbook of Medical-Surgical Nursing. 2018. 14th Edition. Lippincott Williams & Wilkins 56