Lecture Notes

1. 14 Nervous System Lecture Notes Classroom Activity to Accompany Medical Terminology Systems, Sixth Edition Barbara A. Gylys ∙ Mary Ellen Wedding

2. 14 NERVOUS SYSTEM Structure of Nervous System • Central Nervous System (CNS) • Brain • Spinal cord • Peripheral Nervous System (PNS) • Peripheral nerves • Basic unit is the neuron

3. 14 NERVOUS SYSTEM Function of Nervous System • Central nervous (CNS) • Control center of the body. • Peripheral nervous system (PNS) • Consists of peripheral nerves and connect CNS to remote body parts to relay and receive messages.

4. 14 NERVOUS SYSTEM Structure and Function Exercise Q: What are the two main divisions of the nervous system? A: Central nervous system (CNS) and peripheral nervous system (PNS). Q: What are the cells that transmit impulses called? A: Neurons Q: What does the CNS consist of? A: Brain and spinal cord Q: What does the PNS consist of? A: Peripheral nerves that connect CNS to remote body parts to relay and receive messages. Q: What is the function of neuroglia cells? A: They perform the function of support and protection, but are not transmitters of messages.

5. 14 NERVOUS SYSTEM Spinal Cord Injuries Signs and Symptoms • Spinal cord injury resulting in paraplegia or quadriplegia usually is a consequence of fracture, dislocation, or both of the vertebral column.

6. 14 NERVOUS SYSTEM Spinal Cord Injuries Signs and Symptoms (continued) • Location of spinal cord injury and severity of trauma determines whether paraplegia or quadriplegia results. • In paraplegia, there is loss of motor and sensory functions in the legs and trunk. • In paraplegia, bowel, bladder, and sexual function may be lost. • Complete spinal cord injury renders no feeling or function beneath the injury. • Incomplete spinal cord injury renders some feeling and function remains beneath the injury.

7. 14 NERVOUS SYSTEM Spinal Cord Injuries Treatment • Restoration and stabilization of the injured spinal area. • Decompression of compressed neurological structures. • Prevent progressive spinal cord tissue damage. • Surgery, drugs, or cooling the affected portion of the spine.

8. 14 NERVOUS SYSTEM Clinically Related Exercise Q: Michelle’s daughter is diagnosed with a spinal cord injury and asks the nurse to explain its cause. A: Acute traumatic injury of the spinal cord that results from automobile accidents, sports injuries, falling, or violence. Q: Jena has a loss of motor and sensory functions in the legs and trunk following an auto accident. This type of spinal injury is known as (paraplegia, quadriplegia, complete spinal injury) A: paraplegia Q: The nurse explains that a C6 injury results in paralysis of all four extremities and usually the trunk. This type of impairment is called (paraplegia, quadriplegia, total paralysis). A: quadriplegia Q: The veteran presents to the clinic with paralysis of the lower portion of the body and both legs. The medical term in the chart for this spinal cord impairment is (paraplegia, quadriplegia, total paralysis). A: paraplegia

9. 14 NERVOUS SYSTEM Spinal Cord Defects Signs and Symptoms • Developmental defects of the first trimester of pregnancy, characterized by incomplete closure of the bones encasing the spinal cord.

10. 14 NERVOUS SYSTEM Spinal Cord Defects Signs and Symptoms (continued) • Spina bifida occulta is the most common and least severe spinal cord defect. • Incomplete closure of one or more vertebrae without protrusion of spinal cord or meninges. • Spina bifida cystica has two classifications: • Meningocele, sac contains only meninges and cerebrospinal fluid (CSF). • Meningomyelocele, sac contains meninges, CSF, and a portion of the spinal cord.

11. 14 NERVOUS SYSTEM Spinal Cord Defects Treatment • Spina bifida occulta usually requires no treatment. • Meningocele and meningomyelocele require surgical repair of sac and supportive measures to promote independence and decrease possibility of complications. • Folic acid in diet of women in the chilbearing age decreases risk of spina bifida.

12. 14 NERVOUS SYSTEM Clinically Related Exercise Q: Mrs. C asks about the importance of taking a folic acid vitamin supplement during pregnancy. A: The MA explains that folic acid intake decreases risk of the child being born with the congenital defect called spina bifida. Q: The Smith baby is diagnosed with spina bifida cystica and the mother asks the physician to explain this congenital defect. A: The doctor states that spina bifida cystica involves protrusion of the meninges (meningocele), or spinal cord (myelocele), or both (meningomyelocele). Q: The parents ask the nurse to explain the type of treatment recommended for spina bifida occulta. A: She explains that spina bifida occulta does not require surgery and there is little or no treatment.

13. 14 NERVOUS SYSTEM Clinically Related Exercise (continued) Q: Baby Mary is diagnosed with spina bifida that involves protrusion of the meninges. The medical term for this is (meningocele, meningomyelocele, myelocele). A: meningocele Q: Baby Mark is diagnosed with spina bifida cystica that involves the protrusion of the meninges and spinal cord. This diagnosis is charted as (meningocele, meningomyelocele, myelocele). A: meningomyelocele

14. 14 NERVOUS SYSTEM Medical Vocabulary • angioma • anorexia • aphasia • cognition • craniotomy • dementia

15. 14 NERVOUS SYSTEM Medical Vocabulary (continued) • dysphasia • epilepsy • hydrocephalus • neurolysis • neurosis • oxytocin

16. 14 NERVOUS SYSTEM Medical Vocabulary (continued) • neurotransmitter • palsy • parapleglia • psychosis • quadriplegia • shingles

17. 14 NERVOUS SYSTEM Diagnostic Procedures • Cerebrospinal fluid (CSF) analysis • Lumbar puncture • Sample of CSF is withdrawn for laboratory analysis as shown in the illustration.

18. 14 NERVOUS SYSTEM Word Building Exercise Q: Pertaining to the cerebrum and spine: A: cerebrospinal Q: Incision of the cranium (skull): A: craniotomy Q: Crushing a nerve: A: neurotripsy Q: Hernia of meninges and spinal cord: A: meningomyelocele Q: Inflammation of gray matter of spinal cord: A: poliomyelitis Q: Paralysis of four (limbs): A: quadriplegia

19. 14 NERVOUS SYSTEM Medical and Surgical Procedures • Craniotomy • Thalamotomy • Tractotomy • Vagotomy

20. 14 NERVOUS SYSTEM Clinically Related Exercise Q: Susan is diagnosed with ulcers in the stomach and duodenum that do not respond to medication or changes in diet. Dr. S. recommends a surgical procedure of the vagus nerve to relieve her peptic ulcer disease. This is known as a (thalamotomy, tractotomy, vagotomy). A: vagotomy Q: John suffers from chronic pain caused by an injury to his back from an auto accident 10 years ago. The doctor performs a partial destruction of the thalamus to treat his chronic pain. This is charted in the medical record as a __________________. A: thalamotomy Q: Zia is having surgery to remove a brain tumor. The surgeon needs to create an opening in the skull to gain access to the tumor. This surgery is known as a (craniotomy, thalamotomy, tractotomy). A: craniotomy Q: The neurosurgeon performs a transection of a nerve tract in the spinal cord to resolve the patient’s chronic pain. This surgical procedure is charted as a (craniotomy, thalamotomy, tractotomy). A: tractotomy

21. 14 NERVOUS SYSTEM Pharmacology • Anesthetics • general • local • Anticonvulsants • Antiparkinsonian agents

22. 14 NERVOUS SYSTEM Clinically Related Exercise Q: To control Parkinsonian tremors, the physician prescribes an (anticonvulsant agent, antibiotic agent, antiparkinsonian agent). A: antiparkinsonian agent Q: Pat is scheduled for a craniotomy. The anesthesiologist informs her that she will be unconscious during the procedure and a (general, central, local, ___________ anesthetic will be administered. A: general Q: To control seizures, the physician prescribes an (anesthetic, anticonvulsant, antiparkinsonian) A: anticonvulsant Q: Mrs. C is informed that she will be under local anesthesia for her minor procedure and asks if she will be unconscious. A: The nurse explains that anesthetics that produce loss of feeling only affect a local area; there is no loss of consciousness.