Sensory alterations- nervous system

Question 1

Increased Intracranial Pressure (IICP)

Answer 1

elevation of cerebrospinal fluid pressure. pressure normally increases with deep abdominal breathing, coughing and straining with defecation. Pressure abnormally increases with altered CSF or cerebral blood circulation, brain tumor, injury, edema or CVA. This leads to decreased LOC due to decreased O2 supply to brain stem or cerebral cortex, fixed and dilated pupils, increased systolic BP, bradycardia, cheyne-stokes.

Question 2

Cerebral edema

Answer 2

increase in fluid content that causes IICP, focal neurologic defects (opposite side of body affected), and altered LOC. With cerebral edema, there is little room for expansion and the lymphatic system is absent, so the excess fluid isn’t filtered. Instead F&E balance is controlled by the blood-brain barrier

Question 3

Hydrocephalus

Answer 3

Excess fluid in the cranial vault, subarachnoid or both b/c of an increase in CSF volume due to overproduction, obstruction in the ventricular system, or decreased absorption of CSF. Signs include enlargement of the head with protrusions of the fontanals in infants (and projectile vomiting), and symptoms of IICP in adults

Question 4

Cerebrovascular accident CVA

Answer 4

stroke, sudden neurologic episode caused by a deficit in blood supply to an area of the brain. Can be caused by hemorrhage, thrombus, or embolus.

Question 5

Thrombotic stroke

Answer 5

most common type, where the predisposition for experiencing a stroke is atherosclerosis. Onset is gradual, evolving over many days and progressing from transient ischemic attacks (some blockage) to stroke-in-evolution to completed stroke (total blockage). Symptoms are during sleep or after awakening in AM and present as a slow decrease in function. Including: rapid hemiplegia, loss of consciousness, severe headache, stiff neck, blood in spinal fluid.

Question 6

Embolitic stroke

Answer 6

stroke caused by fragments that separated from a thrombus outside the brain. Predisposition includes thrombus in the left heart, atherosclerosis, or chronic atrial fibrillation. This type causes more damage than a thrombotic stroke and usually occurs in younger persons, with a sudden onset not related to activity. Usually a second stroke follows at some point b/c the source of the emboli continues to exist. Symptoms: rapid hemiplegia, loss of consciousness, severe headache, stiff neck, blood in spinal fluid, affected walking, ADLS, speech and mental abilities.

Question 7

Hemorrhagic stroke

Answer 7

usually occurs in relationship to mild exertion and in persons who have progressive HTN. Onset is while p. is active, not usually during rest. Symptoms: rapid hemiplegia, loss of consciousness, severe headache, stiff neck, blood in spinal fluid, Affects ambulation speech, mentation, ADLS

Question 8

Astrocytoma

Answer 8

slow growing infiltrative gliomas (glial cells provide nutrients to brain) that are most common in middle age within the cerebral hemispheres, and that forms cavities known as pseudocysts. Growth is in a star/flower like pattern. Tumor tends to become more anaplastic over time and may become a glioblastoma. Common S&S: IICP–headache and vomiting, papilledema from venous stasis– blurred vision, halo around lights, location symptoms, seizures.

Question 9

Glioblastoma multiform

Answer 9

most anaplastic of gliomas that develops from existing astrocytomas by progressive loss of differentiation. Growth is most common in the cerebral hemispheres- frontal lobes. Symptoms are rapid and progressive- IICP–headache and vomiting (if IICP in brainstem), papilledema– blurred vision and halo around lights, location symptoms, seizures.

Question 10

Meningioma

Answer 10

primary tumor that originates from the dura mater or arachnoid membranes. Tumor is slow growing, encapsulated, benign, and may remain silent. Most frequent in middle aged adults and easier to remove/treat than astrocytomas. S&S: IICP–headache, vomiting, papilledema, blurred vision, location symptoms, seizures

Question 11

Epidural (extradural) Hematoma

Answer 11

Collection of blood b/w the skull and dura mater (epidural space) and is usually the result of a tear in the middle meningeal artery or vein. Common causes= MVAs, minor falls, sport accidents. S&S develop within minutes to few hours= skull fracture, classic symptoms are patterns of unconsciousness to consciousness to unconsciousness. ipsilateral pupil dilation, contralateral hemiparesis (opposite side of body affected), IICP. This type has a good prognosis with early intervention

Question 12

Subdural Hematoma

Answer 12

collection of blood b/w the dura mater and arachnoid membrane which is venous in nature. Causes by MVAs or falls (especially in elderly or alcoholics). There is blunt trauma without skull fracture. Acute- 50% die from, obvious trauma, delayed onset of symptoms, fluctuating LOCs. Subacute- over 48hrs to 2 weeks. Chronic- weeks to months, trauma may seem insignificant or forgotten, difficult to dx, frequent with elders/alcoholics, chronic headaches and tenderness over hematoma.

Question 13

Seizures

Answer 13

symptom R/T spontaneous, uncontrolled, transitory nervous discharge. Etiology is R/T epilepsy, acquired factors, congenital lesions, genetics, myoclonic syndromes… Usually involves motor, sensory, autonomic, or psychic S&S and altered LOC.

Question 14

Generalized seizures

Answer 14

class of seizures that is characterized by onset of bilateral, symmetrical, epileptic activity. Consciousness is always impaired or lost, they do not have a local onset, usually originate from subcortical or deeper brain tissue. Class includes: petit mal and grand mal seizures

Question 15

petit mal seizures

Answer 15

a type of generalized seizures in which there is a short lapse in consciousness indicated by a brief pause in conversation, a vacant stare or rapid blinking of eyes. This type is almost exclusively in children

Question 16

Grand mal seizures

Answer 16

a type of generalized seizures in which there is (tensing) tonic/clonic spasms of muscles. This is the classic seizure of epilepsy and is generally preceded by an aura. There is loss of consciousness, clenching of teeth which can sever the tongue, bladder/bowel incontinence, mental confusion and amnesia for event.

Question 17

Partial seizures (focal)

Answer 17

class of seizures that start with a localized activation of neurons and generally do not involve the whole brain or significantly impair consciousness or memory. Includes simple (consciousness is preserved) and complex (“ “ impaired) seizures.

Question 18

Jacksonian seizures

Answer 18

a type of partial-simple seizures in which there is a focal onset, usually unilateral spasm or twitching of the fingers or face which may spread in a progressive march to involve the entire side.

Question 19

Alzheimer’s disease

Answer 19

Chronic neurologic disorder characterized by progressive and selective degeneration of neurons in the cerebral cortex and certain subcortical structures. Has been linked to a loss of the enzyme choline acetyltransferase resulting in a deficit in acetylcholine (excites neurons) in acetylcholine releasing neurons. Autopsy findings include neuronal tangles, the axons of which coalesce into senile plaques which contain aluminum deposits, dead nerve terminals and abnormal protein fragments. Protein fragments always contain amyloid precursor protein (APP).

Question 20

Alzheimer’s disease S&S

Answer 20

Recent/progressive memory loss, acalculia (can’t perform simple arithmetic), personality changes, mentally alert without clouding of consciousness, advanced extrapyramidal involvement (lose ability to walk, swallow, other adls), sundown syndrome with confusion at end of day and nocturnal awakening, agitation. Terminal loss of ability to perceive, think, speak, or move. Death R/T immobility, dehydration and respiratory infection.

Question 21

Parkinson’s disease

Answer 21

iatrogenic degenerative disorder of the basal ganglia (corpus striatum; pt of the extra-pyramidal system that influences initiation/completion of movements) involving the reduction of dopamine in which the severity of motor syndrome is proportional to the dopamine deficiency. Without dopamine the cerebral cortex, basal ganglia, and thalamus are overstimulated by acetylcholine causing excess muscle tone, tremors and rigidity. The characteristic symptom is tremors at rest- called pill rolling- that is decreased with voluntary movement. Other S&S: bradykinesia/akinesia, rigidity, shuffling gait, festinating stooped posture, loss of arm swing movement with gait, poor balance, drooling*, mast face, staring expression, loss of speech modulation.

Question 22

Meningitis

Answer 22

infection of the meninges (epidural and subdural spaces) that is bacterial or fungal in origin. Bacterial meningitis is the result of exotoxins that destroy meningeal cells and cause– fever, photophobia, nuchal rigidity, delirium, LOC change, positive brudzinski’s (flexion of neck while supine and knees will flex) and kernigs sign. Fungal meningitis do not result in a fever, occur in p. who are immunosuppressed (HIV/AIDS), with slow/insidious symptoms. The first manifestations are those of dementia

Question 23

Multiple Sclerosis (MS)

Answer 23

iatrogenic degenerative disorder involving CNS myelin (white matter) with onset usually 20-50 years old. It is most common father from the equator (more changes with seasons and increased flu infections), and is associated with slow viral or other infectious agent. Abs produced destroy myelin causing scar tissue plaques and slowed neural transmission. S&S partially resolve & then return= optic neuritis– diplopia, scotomas (blind spots), emotional changes, seizures, hemiparesis, hemisensory loss, dysphagia, motor ataxia, hypotonia of muscles, asthenia (loss of strength), paralysis of eye muscles, nystagmus (rapid eye movement), dysarthria, spastic paresis, bowel/bladder dysfunction, S&S exacerbated by stress. Death from immobility or DVT.

Question 24

Myasthenia Gravis

Answer 24

untreatable chronic, autoimmune disease of voluntary (striated) muscles. The defect is in the nerve impulse transmission at the neuromuscular junction where postsynaptic acetylcholine receptors on muscle cells are blocked and destroyed by autoimmune IgG Abs. S&S= gradual weakness and fatigue, weakness in ocular muscles- ptosis and diplopia, progessn to muscle cranial nerves with difficulty chewing, swallowing, phonating and smiling. Progession to vagus nerve with decrease thoracic expansion- difficulty breathing. Eventually there is no recovery of strength after rest.

Question 25

Spinal cord injuries

Answer 25

trauma causing neuronal, axonal and myelin sheath shearing and crushing with local necrosis and hemorrhage. Can be complete SCI, with severing of cord and total loss of function, or incomplete with some motor/sensory function retained. Complications of SCIs include– respiratory failure (loss of nerve innervation), spinal cord shock– complete loss of sensory, motor, autonomic function leading to hypotension, bradycardia, warm, dry extremeties, absent reflexes, flaccid paralysis below trauma. Other S&S- orthostatic hypotension, DVT, complications of immobility.

Question 26

Spina Bifida (pediatric)

Answer 26

congenital neural tube defect C/B a failure of the vertebral arches to close resulting in a cystlike protrusion of either the meninges alone (meningocele) or of the meninges and the spinal cord (myelomeningocele) out of the vertebral column. Another type is spina bifida occulta in which minor irregularities in the vertebral arches aren’t obvious at birth

Question 27

Meningocele (pediatric)

Answer 27

type of spina bifida with protrusion of the meninges out of the spinal cord. Neural tissue is not exposed, so neural deficits are absent or minor. S&S= may be symptomless, saclike protrusion of meninges and CSF from the back,, club foot, gait disturbance, and bladder incontinence.

Question 28

Myelomeningocele (pediatric)

Answer 28

type of spina bifida w/ protrusion of the meninges and spinal cord through the vertebral arches. This may result in loss of nerve function and paralysis. Also causes neurological defects at and below the site of exposure.

Question 29

Reye syndrome (pediatric)

Answer 29

encephalopathy and fatty changes of the organs, especially the liver, associated with ingestion of aspirin during an infection or illness. Typically develops in children recovering from varicella, URI, influenza B and gastroenteritis. Manifests in stages with progressive changes in LOC, reflexes, and neuromuscular function.

Question 30

Meningitis (pediatric)

Answer 30

infection of the meninges caused by bacteria, viruses, fungi, parasites or toxins that have spread from other areas like the sinuses, ears, or upper resp. tract. S&S= IICP–headache, decreased consciousness, papilledema, and vomiting, fever from infection, photophobia, neck stiffness, pain from irritation, positive brudzinski’s and kernigs sign