Neurological

COMMON LAB TESTS FOR NEUROLOGICAL DISORDERS: CEREBROSPINAL FLUID

1. Appearance colorless, clear 2. Pressure 50-180 mm H2O 3. Protein

a. Lumbar 15-50 mg/dl b. Cisternal 15-25 mg/dl c. Ventricular 6-15 mg/dl

4. Cell Count a. RBCs negative b. WBCs 0-5

5. Glucose 50-80 mg/dl 6. Gram stain negative for organisms 7. Culture and sensitivity: no growth

Cerebrospinal fluid analysis

a. obtained via lumbar, cisternal or ventricular puncture b. indications: inflammation, infection c. standard precautions are required d. maintain strict asepsis

Cerebrospinal Fluid (CSF)

Definition: A watery cushion that protects the brain and spinal cord from physical impact and bathes the brain in electrolytes and proteins.

Formation: The fluid is formed by the choroid plexuses of the lateral and third ventricles. That of the lateral ventricles passes through the foramen of Monro to the third ventricle, and through the aqueduct of Sylvius to the fourth ventricle. There it may escape through the central foramen of Magendie or the lateral foramina of Luschke into the cisterna magna and to the cranial and spinal subarachnoid spaces. It is reabsorbed through the arachnoid villi into the blood in the cranial venous sinuses, and through the perineural lymph spaces of both the brain and the cord.

Characteristics: The fluid is normally watery, clear, colorless, and almost entirely free of cells. The initial pressure of spinal fluid in a side-lying adult is about 100 to 180 mm of water. On average, the total protein is about 15 to 50 mg/dl, and the concentration of glucose is about two-thirds the concentration of glucose in the patient's serum. Its pH, which is rarely measured clinically, is slightly more acidic than the pH of blood. Its concentration and alkaline reserve are similar to those of blood. It does not clot on standing. Turbidity suggests an excessively high number of cells in the fluid, typically white blood cells in infection or red blood cells in hemorrhage.

CSF may appear red following a recent subarachnoid hemorrhage or when the lumbar puncture that obtained the CSF caused traumatic injury to the dura that surround the fluid. Centrifugation of the fluid can distinguish between these two sources of blood in the spinal fluid: the supernatant is usually stained yellow (xanthochromic) only when there has been a recent subarachnoid hemorrhage.

Many conditions may cause increases in total protein: infections, such as acute or chronic meningitis; multiple sclerosis (when oligoclonal protein bands are present); Guillain-Barré syndrome; and chronic medical conditions like cirrhosis and hypothyroidism (when diffuse hypergammaglobulinemia is present). The concentration of glucose in the CSF rises in uncontrolled diabetes mellitus and drops precipitously in meningitis, sarcoidosis, and some other illnesses. Malignant cells in the CSF, demonstrated after centrifugation or filtering, are hallmarks of carcinomatous meningitis.

Microorganism: The CSF is normally sterile. Meningococci, streptococci, Haemophilus influenzae, Listeria monocytogenes , and gram-negative bacilli are recovered from the CSF only in cases of meningitis. Syphilitic meningitis is usually diagnosed with serological tests for the disease, such as the venereal disease research laboratory (VDRL) test, the rapid plasma reagin (RPR) test, or the fluorescent treponemal antibody test. Cryptococcal infection of the CSF may be demonstrated by India ink preparations, or by latex agglutination tests. Tuberculous meningitis may sometimes be diagnosed with Ziehl-Neelsen stains, but more often this is done with cultures. These last three infections (syphilis, cryptococcosis, and tuberculosis) are much more common in patients who have acquired immunodeficiency syndrome (AIDS) than in the general population.

Electroencephalogram (EEG)

a. records electrical activity at various brain sites b. specific nursing interventions

i. do not stop anticonvulsant medications ii. the night before test, adult clients should have minimal sleep iii. hair should be washed prior to test iv. after test, help client remove paste

Tomography and resonance imaging

Computerized tomography (CT) scans a. use a roentgen ray and a computer to provide accurate images of cross sections

of the body b. a non-invasive procedure using very little radiation that visualizes slices of

tissues c. usually takes less than one hour d. sharper images than conventional x-rays e. contraindicated in pregnancy f. nursing interventions

i. explain test to client ii. some clients may require mild sedation iii. client must lie very still iv. client receives radiopaque solution to visualize blood vessels v. client is NPO past midnight when contrast is used vi. if barium studies were done, wait at least four days for CT scan, or barium

will obscure film

Positive emission tomography (PET)

a. uses an intravenous injection of radioactive substance followed by a head scan b. various shades of color indicate levels of glucose metabolism in the brain c. nursing interventions: same as CT scan

Magnetic resonance imaging (MRI)

a. tomography based on the magnetic behavior of protons in the body tissues b. used to detect neurologic and musculoskeletal disorders c. contraindicated in clients with metal implants such as pacemakers, aneurysm

clips, medication patches that are foil backed, metallic orthopedic devices, can be uncomfortable with multiple tattoos

d. nursing interventions i. explain test to client ii. client must lie very still iii. client may become claustrophobic in chamber iv. soft humming sound may annoy some clients v. client must remove all metal jewelry and watches

Lumbar puncture (LP) (Spinal Tap)

a. needle inserted into the subarachnoid space between L3 and S1 b. uses

i. measure cerebrospinal fluid (CSF) pressure ii. obtain CSF for visual and laboratory examination iii. to inject medications, anesthetic agents, diagnostic agents.

1. Contraindicated if client has increased intracranial pressure (ICP) 2. Place client in lateral decubitus position (knee-chest) 3. Complications include post-puncture headache 4. CSF findings

5. Nursing interventions a. explain procedure to client b. administer sedative if ordered

c. assist client to maintain proper position and stillness during procedure d. strict asepsis e. maintain standard precautions f. label specimens sequentially g. provide emotional support as procedure can be painful h. post-procedure

i. keep client flat on back from four to 12 hours ii. give analgesics & ice pack as ordered iii. perform neuro checks and vital signs prequently to assure

stability iv. encourage fluids unless contraindicated v. observe for post-puncture headache, leakage of CSF, tingling

sensation, numbness or pain in lower extremities

Intracranial pressure (ICP) monitoring

a. invasive: measuring device is placed i. in a ventricle ii. in a subarachnoid space iii. outside dura mater iv. within parenchyma

b. types of devices include aventricular catheter; a subarachnoid bolt; an epidural sensor

c. changes in intracranial pressure are converted to an electrical impulse by a transducer and displayed on a screen or on graph paper

d. measurements include volume-pressure relationships, pressure waves and cerebral perfusion pressures

e. normal ICP: 10-15 mm Hg f. nursing interventions

i. maintain strict sterile technique ii. maintain patency of device iii. observe for CSF leaks or bleeding, signs of infection iv. monitor pressure and report deviations

I. Neurological Anatomy and Physiology

A. Central nervous system (CNS) - coordinates and controls body functions 1. Brain

a. cerebrum i. hemispheres right and left ii. frontal lobe - higher intellectual functions, social

behavior, personality iii. parietal lobe - perceives and interprets sensory

input iv. temporal lobe - emotional response, memory,

language, organization of sensory input (hearing, taste and smell)

v. occipital lobe - vision b. cerebellum - provide equilibrium and muscle coordination c. brain stem - midbrain, pons and medulla oblongata;

controls basic body functions and relays impulses to and

from spinal cord; the connection between the brain and spinal cord

2. Spinal cord a. descending tract - anterior portion of cord carrying motor

information; associate "d"escending to "d"own impulses are carried to peripheral nerves

b. ascending tract i. the posterior portion of cord that carries sensory

information up to the brain ii. 31 segments

eight cervical: neck and upper extremities 12 thoracic: thoracic and abdomen five lumbar: lower extremities five sacral: lower extremities, urine and

bowel control one coccygeal

B. Peripheral nervous system - carries information to and from the CNS 1. Motor nerves 2. Sensory nerves

C. Autonomic nervous system - regulates body's internal environment 1. Sympathetic - prepares body for fight or flight; used only as

needed when scared or excessively happy

2. Parasympathetic - controls normal body functioning for day to day activities, e.g., increases muscle tone, maintains secretions with moist mucous membranes; maintains heart rate within normal limits; maintains GI and GU peristalsis

D. Cranial nerves

These nerves are the vital bridges between the brain and the rest of the body.

E. Physiology - nervous system coordinates and controls all activities of the body

1. Receives internal and external stimuli 2. Processes information to determine appropriate response 3. Transmits information over varied motor pathways to effector

organs F. Findings for increased intracranial pressure (ICP)

1. Early a. change in level of consicousness (LOC): restlessness,

agitation, irritability, disorientation, confusion, lethargy, stupor

b. pupils: dilated ipsilaterally, react slowly to light c. abnormal motor activity: contralateral hemiparesis d. abnormal reflexes - hyper or hypo reflexia e. vital signs within normal parameters

2. Late a. LOC: semicomatose, coma b. pupils: dilated bilaterally and fixed; no reaction to light c. motor function: decorticate posture then decerebrate

posture; flaccid muscles at end stage d. vital signs - increased systolic pressure to result in a

widened pulse pressure, decreased respirations with bradycardia (Tip: heart and lungs go in similar directions - both increase or decrease), temperature initially may rise then fall below normal parameters

II. Degenerative Disorders A. Parkinson's disease

1. Definition: degenerative disorder of the dopamine hydrochloride - producing neurons

a. result: dopamine hydrochloride depletion b. usually occurs in older adults and males more than

females c. etiology unknown

2. Findings: first unilateral, then bilateral movements a. resting tremors of the lips, jaw, tongue, and limbs,

especially a resting pill-rolling tremor of one hand that is absent during sleep. This tremor is often labeled - "non intention" tremor. This is different from an essential or intention tremor in which the tremor is action related and labeled "intention" tremor.

b. bradykinesia c. fatigue d. stiffness and rigidity with movement e. mask-like facial expression often accompanied with

drooling f. slow, shuffling walk in a stooped-over posture; gradually

more difficulty with walking g. difficulty rising from sitting position h. ultimately confined to a wheelchair i. mind stays intact unless other aggravating conditions j. echolalia in most cases

3. Diagnostics a. based on findings with history b. EEG c. MRI d. computerized tomogram (CT scan)

4. Management a. expected outcomes: palliative and to postpone

dependence b. pharmacologic

I. anticholinergics - minimize extrapyramidal effects I. benzotropine mesylate (Cogentin)

II. procyclidine (Kemadrin)II. dopamine hydrochloridergics: Levodopa (L-Dopa)

III. antiparkinsonian agent: amantadine HCl (Symmetrel) reduces rigidity and tremor

IV. MAO inhibitors: selegiline (Eldepryl) V. coenzyme Q-10

VI. others I. selegiline (Carbex)

II. COMT inhibitors III. tolcapone (Tasmar) IV. entacapone (if combined with carbidopa and

levodopa the medication is Stalevo)c. therapies

I. physical II. occupational

III. speech d. surgery: to decrease tremor

I. stereotaxic thalamotomy II. pallidotomy - pinpoint the areas to be treated

surgically III. deep brain stimulation

5. Nursing interventions a. maintain safety of client b. prevent effects of immobility c. foster independence in activities of daily living (ADL)

d. reinforce the use of assistive devices for ambulation as indicated

e. promote good nutrition I. small, frequent meals

II. soft foods III. roughage with sufficient fluids to decrease

constipation f. monitor effectiveness or ineffectiveness of administered

medications g. provide emotional support to client and family members h. teach client

I. when and what side effects of the drugs to report II. the benefits of daily exercise

III. the benefits of "drug holidays"

B. Huntington's disease 1. Definition

a. progressive atrophy of basal ganglia and some parts of cerebral cortex

b. etiology - genetic disorder, autosomal dominant 2. Findings: usually occurs in middle age, increased involuntary

movements, progressive decline in cognitive function a. motor function

I. impaired chewing and swallowing II. chorea

III. dystonic posture IV. gradually becomes bedridden

b. cognitive function: less able to organize, plan and sequence behavior

c. mental function: personality changes, depression, even psychosis

3. Diagnostics: history and physical exam 4. Management

a. expected outcome: postpone dependence b. supportive care for findings c. therapies: speech, physical d. genetic counseling

5. Nursing interventions a. foster independence in ADL b. reinforce the use of assistive devices for ambulation as

needed c. teach client to

I. maintain good nutrition II. get emotional support from support groups, friends

III. seek genetic counseling

C. Amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease) 1. Definition

a. progressive atrophy of spinal muscle; bulbar palsy b. progressive degeneration of the motor neurons of the

anterior horn cells of the spinal cord, brainstem, and motor cortex

c. onset in later middle age; more in men than in women d. clients with ALS usually die within two to six years e. etiology unknown

2. Findings a. usually beginning in the upper body - the head and arms,

the distal portion first b. mild clumsiness progressing to total incapacity c. muscle wasting, atrophy, spasticity d. speech disorders e. no change in sensation or autonomic system

f. death most often from complications: respiratory failure, urinary or pulmonary infections for stasis

g. mind usually intact while client has loss of voluntary and eventually involuntary muscle functions

3. Diagnostics: history and physical exam 4. Management

a. expected outcome: keep functional independence as much as possible

b. no cure c. management of findings

I. muscle relaxants for spasticity II. therapies:

I. speech II. physical

III. respiratory support IV. nutritional support

5. Nursing interventions a. provide for respiratory care and referrals b. maintain a safe environment focused toward infection

prevention c. prevent complications of immobility especially pulmonary

and urinary stasis d. postpone dependence e. promote balanced nutrition f. provide emotional support and referrals to support groups

D. Dementia 1. Etiology

a. characterized by irreversible, progressive cerebral dysfunction

b. Alzheimer's disease - most common cause of dementia I. characterized by brain atrophy

II. development of senile plaques and neurofibrillary tangles in the cerebral hemispheres

III. etiology unknown 2. Findings

a. initially characterized by decreased intellectual functioning b. Alzheimer's disease has three stages

I. early stage I. memory loss

II. subtle personality changes III. difficulty with abstract thinking

II. middle stage I. impaired judgment

II. impaired language III. difficulty with motor activity and object

recognition IV. wandering V. inability to carry out ADL

III. final stage I. complete loss of language function

II. loss of bowel and bladder control c. prognosis - poor, incurable

3. Management - expected outcome: maintenance of functional capacity

4. Nursing interventions a. meet client's physical needs b. promote client's independence c. promote contact with reality d. assist client/family to establish a routine e. provide emotional support or caregiver support with

appropriate referrals

E. Organic brain syndrome 1. Definition - a general term used to categorize physical conditions

that can cause decreased mental function 2. Etiology

a. degenerative disorders b. drug and alcohol related conditions c. infections d. repiratory conditions

e. trauma-induced brain injury f. cardiovascular disorders g. dementia from metabolic disorders

3. Findings a. findings vary with the specific disease b. in general, organic brain syndromes cause varying

degrees of confusion c. delirium - severe often sudden short term loss of brain

function as with high temperatures, drug withdrawal d. agitation e. dementia - long term loss of brain function f. aggression - typical of some of the conditions contributing

to this diagnosis 4. Management

a. therapy varies with the specific disorder b. many of the disorders have nonspecific treatments c. the priority in many instances is supportive care to assist

the person in areas where brain function is lost d. medications may be needed to reduce aggressive

behaviors typical of some of the conditions in this category 5. Nursing interventions

a. assist to meet the client's physical needs b. refer family to support systems c. monitor the effectiveness of medication therapy d. evaluate changes to where the client is unable to maintain

independence with ADL

III. Cerebrovascular Accident (CVA, Stroke, Cerebral Infarction) A. Definition: decreased blood supply to the brain

1. Risk factors a. hypertension, uncontrolled b. smoking c. obesity d. increased blood cholesterol and triglycerides e. chronic atrial fibrillation

2. Five classes of stroke: by "severity" - least to most severe a. transient ischemic attack (TIA), "angina" of the brain

i. TIA is warning sign of stroke ii. localized ischemic event iii. produces neurological deficits lasting only minutes

or hours iv. full functional recovery within 24 to 48 hours

b. reversible ischemic neurological deficit (RIND) i. similar to TIA

ii. findings last between 24 hours and three weeks iii. usual full functional recovery within three to four

weeks c. partial, nonprogressing stroke: some neurological deficit,

but stabilized d. progressing stroke (stroke in evolution)

i. deterioration of neurological status often with grand mal seizure activity

ii. has residual neurological deficits that last indefinitely

e. completed stroke - results from a stroke in evolution

3. Two types of stroke by "cause" a. ischemic (also known as occlusive) stroke (clot) - slower

onset i. results from inadequate blood flow leading to a

cerebral infarction ii. caused by cerebral thrombosis or embolism within

the cerebral blood vessels iii. most common cause: atherosclerosis

b. hemorrhagic stroke (bleeding) - abrupt onset i. intracerebral hemorrhagic stroke

blood vessels rupture with a bleed into the brain

occurs most often in hypertensive older adults

may also result during anticoagulant or thrombolytic therapy

ii. subarachnoid hemorrhage (SAH) most often caused by rupture of saccular

intracranial aneurysms more than 90% are congenital aneurysms

iii. epidural bleeds cerebral arterial vessels are involved often a loss of consciousness for a short

period of time called transient unconsciousness

recall clue: associate that "e" in epidural and "a" in artery are together at the top of the alphabet

iv. subdural bleeds veins are involved may not be evident until months after an

initial trauma recall clue: associate that "s" in subdural

and "v" in vein are together at the bottom of the alphabet

B. Findings (depends on the location of the lesion)

 Types of CVA

 

C. Diagnostics 1. History and physical exam 2. Computerized tomogram (CT) scan 3. Magnetic resenance imaging (MRI) 4. Doppler echocardiography flow analysis 5. Carotid artery duplex doppler ultrasonography 6. EEG - shows abnormal electrical activity 7. Lumbar puncture - shows if blood is found in the cerebral spinal

fluid as a result of a cerebral bleed 8. Cerebral angiography - shows blood flow in cerebral arteries

a. may be done with or without contrast D. Management - to prevent or minimize the damaging effects of stroke;

dependent on the type of CVA 1. Expected outcomes

a. prevent or minimize the damaging effects of stoke b. depends on the type of CVA

2. Occlusive stroke a. pharmacologic

1. thrombolytics 2. anticoagulant therapy: heparin, coumadin 3. antiplatelet therapy: aspirin, dipyridamole

(Persantine) 1. platelet aggregation inhibitor: clopidogrel

(Plavix), ticlopidine HCL (Ticlid) 4. steroids: dexamethasone (Decadron)

b. surgery - bypass - carotid endarterectomy

3. Hemorrhagic stroke a. pharmacologic

1. antihypertensive agents 2. systemic steroids: dexamethasone (Decadron) 3. osmotic diuretics: mannitol 4. antifibrinolytic agents: aminocaproic acid (Amicar) 5. vasodilators 6. alpha-blockers and beta-blockers 7. anticonvulsants

b. surgical excision of aneurysm 4. Common to both types of stroke

a. care based on findings b. therapies

1. nutritional support 2. physical 3. speech 4. behavioral 5. occupational

E. Nursing interventions 1. In acute stage of stroke

a. maintain airway patency; if grand mal seizure activity note time, length, behaviors

b. monitor neuro status and vital signs c. maintain adequate fluids d. position with head of bed elevated 15 to 30 degrees with

client turned or tilted to unaffected side e. provide activity as ordered f. perform passive and/or active range of motion exercises g. maintain client's proper body alignment h. administer medications as ordered i. care for post op client as indicated j. provide care for client with increased intracranial pressure 

2. Long-term care of client with stroke a. monitor to facilitate normal elimination patterns b. teach/evaluate the use of supportive devices c. maintain client in a safe environment d. prevent the effects of immobility e. support the maintenance of adequate nutrition in light of

feeding and swallowing problems f. assist with eating and ADL as indicated g. provide emotional support h. provide methods of communication for client with aphasia

IV. Infectious Inflammatory Disorders

CARE OF CLIENT WITH INCREASED INTRACRANIAL PRESSURE

1. Institute seizure precautions 2. Administer oxygen as ordered 3. Monitor for changes in intracranial pressure 4. Monitor neuro vital signs as ordered 5. Maintain fluid restriction as ordered 6. Observe for herniation syndrome 7. Raise head of bed at 30-45 degrees; avoid 90 degrees since pressure in hip area increases ICP 8. Prevent any activities that increase ICP such as: laughing, straining at stool, coughing, vomiting,

any restrictive clothing around neck, anxiety, pushing up in bed with heels, pulling on rails when turning, neck rotation, flexion or extension

9. Provide for the care of the unconscious clients if decreased LOC

A. Meningitis

1. Definition/course a. acute or chronic inflammation of the meninges b. average length of illness is four months

2. Types a. bacterial: mostly contagious; requires isolation

i. mostly common meningococcal the covering of the brain and spinal cord are

involved in children 2 to 18 years-old in high risk groups

o infants o adults with weakened or suppressed

immune systems o college students – freshman in

particular who reside in dormitories o travelers to foreign countries where

disease is endemic o 10 – 15% of cases are fatal o 10 – 15 % of cases result in brain

damage or other serious side effects ii. Haemophilus influenzae; those at risk are

children in child care settings children with no access to vaccine

iii. pneumococcal; those at risk are children under the age of 2 years-old adults with weakened or suppressed

immune systems b. viral

i. isolation is not required ii. aseptic meningitis is the most common form in the

USA c. cryptococcal fungal

i. often from bird droppings ii. organism is found in dirt iii. common in clients with AIDS

3. Findings a. severe headache

b. sudden fever c. altered LOC – decreased d. photophobia e. nuchal rigidity – severe pain in the back of neck when the

chin is moved toward the chest with the client resisting movement

4. Diagnostics a. history and physical exam b. positive Kernig's sign: 90-degree flexion of hip and knee

with extension of knee causes pain c. positive Brudzinski's sign: flexion of neck causes flexion of

hip and knee d. lumbar puncture for characteristics of cerebral spinal fluid -

decreased glucose in bacterial or fungal infections e. CT or MRI with and without contrast f. EEG

5. Management a. expected outcomes: to cure the infection and prevent

complications b. pharmacologic

i. antibiotic therapy depends on the type of pathogen ii. preventive therapy for people exposed to those with

meningococcal or haemophilus influenzae (H flu) meningitis: rifampin (rifadin)

iii. H flu vaccine iv. antifungals if fungus v. anticonvulsants to prevent seizures

c. actions to minimize fever d. prevention of increased intracranial pressure or seizures

6. Nursing interventions a. care of client with increased ICP  b. seizure precautions  c. administer drugs as ordered d. provide comfort measures for pain

e. reduce external stimuli and lighting if photophobia

B. Parameningeal infections 1. Definition

a. localized collection of exudate in the brain or in the spinal cord

b. a recurrent aseptic meningitis c. considered noninfectious

2. Findings a. similar to meningitis

SEIZURE PRECAUTIONS

Before seizure 1. Bed rest with padded side rails 2. Suction available at the bedside 3. Oxygen available at bedside

During seizures 1. Loosen any tight or restrictive clothing. 2. If clients are falling, gently help them to the ground and position clients on their side. 3. Do not place anything in the mouth. 4. Observe the seizure as it runs its course. 5. If it lasts longer than 5 minutes, notify health care provider immediately. 6. Note the activity and the time it begun and ended.

Daily life precautions 1. For children discourage climbing over 10 feet high. 2. Recommend for clients not to lock bathroom or shower doors. 3. If swimming, clients are to have someone with them who can rescue. 4. If old enough to drive, clients should be seizure free for six months. The time may vary in some

states.

b. headache, fever, stiff neck, altered consciousness - decreased

3. Diagnostics a. NO lumbar puncture; may cause herniation b. computerized tomogram (CT) scan

4. Management a. expected outcomes: to cure infection and prevent

complications b. surgical decompression of abscess c. symptomatic and preventive treatment as with meningitis d. drugs: antibiotics

5. Nursing interventions: same as meningitis except that infectious precautions are not required

C. Encephalitis 1. Definition

a. acute viral or less commonly bacterial inflammation, irritation and swelling on the brain tissue

b. can occur as epidemics or sporadically c. death rate ranges up to 70% d. most cases in the USA associated with sporadic

encephalitis is herpes simplex virus types 1 and 2, rabies virus, or arboviruses from the bite of infected ticks, mosquito or other blood sucking insects, i.e., Equine, La Crosse, St. Louis, West Nile

e. may follow a systemic viral illness such as chicken pox 2. Findings

a. adult 1. sudden fever 2. severe headache 3. altered LOC – decreased progressing to stupor

then coma with seizure activity 4. nuchal rigidity 5. speech or hearing de 6. change in personality 7. mild flu-like complaints

b. infant 1. vomiting 2. body stiffness 3. constant crying that worsens when child picked up 4. constant full or bulging anterior fontanel

3. Diagnostics a. history and physical exam b. CT scan, MRI, EEG c. brain biopsy d. cerebral spinal fluid – decreased glucose suggests

bacterial or fungal infection 4. Management

a. expected outcomes: to cure infection and prevent infections

b. uncomplicated cases require supportive and preventive care

c. bed or chair rest d. support nutritional needs e. monitor for fluid balance maintenance f. herpes simplex calls for antivirals: vidarabine (viraA),

acyclovir (Zovirax)

g. prevention of increased ICP h. antivirals such as acyclovir or ganciclovir i. anticonvulsants - prevent seizures

5. Nursing interventions a. comfort measures for fever b. administer drugs as ordered c. seizure precautions  d. care of the client with increased ICP  e. when needed, ensure isolation and airborne-droplet

precautions

V. Various Disorders of the Neurologic System A. Multiple sclerosis

1. Definition a. demyelination of white matter throughout brain and spinal

cord b. third most common cause of disability in clients aged 15 to

60 c. specific cause unknown d. increased incidence in temperate to cool climates e. illness improves and worsens unpredictably

2. Findings depend on the location of the demyelination a. cranial nerve: blurred vision, dysphagia, diplopia, facial

weakness and/or numbness b. motor: weakness, paralysis, spasticity, gait disturbances c. sensory: paresthesias, decreased proprioception d. cerebellar: dysarthria, tremor, incoordination, ataxia,

vertigo e. cognitive: decreased short-term memory, difficulty with

new information, word-finding difficulty, short attention span

f. urinary retention or incontinence g. loss of bowel control h. sexual dysfunction i. fatigue

3. Diagnostics a. history and physical exam b. lumbar puncture c. magnetic resonance imagery (MRI) d. computerized tomogram (CT) scan e. evoked potentials or response - the EEG record of

electrical activity at one of several levels in the CNS by stimulation of an area of the sensory nerve system

4. Management a. expected outcomes: to alleviate findings and prevent

complications b. pharmacologic: adrenocorticotropic hormone (ACTH) c. therapies based on findings

I. physical II. occupational

III. pharmacologic 5. Nursing interventions

a. maintain client's functional independence in ADL b. determine effectiveness of administed medications c. prevent complications of immobility d. prevent injury from difficulties walking

e. provide emotional support to client and family f. provide counseling for sexual dysfunction

g. teach client to: I. avoid fatigue and stress

II. conserve energy III. exercise regularly IV. know drugs and side effects V. use self-help devices

VI. maintain a diet that supports nutrition and energy needs

B. Guillain-Barre syndrome 1. Definition

a. acquired inflammatory disease b. process: demyelinization of peripheral nerves c. precipitating factors include prior bacterial or viral infection

within one to two weeks 2. Findings

a. muscle weakness: progressive, ascending, bilateral b. leads to paralysis of voluntary muscles c. loss of superficial and deep tendon reflexes d. bulbar weakness e. dysphagia f. dysarthria

g. respiratory failure h. sensory findings: paresthesias, burning pain i. paralysis may vary from being total to partial of only one-

half way up the body3. Diagnostics

a. history and physical exam b. lumbar puncture will show increased protein in CSF c. electromyography (EMG)

4. Management a. expected outcomes: to prevent complications and maintain

body functions until any reversal b. steroids in acute phase c. care as dictated by areas involved

5. Nursing interventions a. maintain the care of client on ventilatory support  b. provide for care of the immobilized client c. have a safe environment to minimize infection d. maintain nutrition and fluid balance e. refer families or client to support groups f. supply referrals to therapies such as speech, physical,

occupational and counseling

CARE OF THE CLIENT ON VENTILATOR

Nutrition

1. Administer as ordered a. IV fluids, meds b. Enteral feedings

2. Evaluate for a. balanced fluid intake and output b. adequate and balanced nutrition

Hygiene 1. Provide

a. a rigorous, scheduled mouth care – prevents ventilator acquired pneumonia

bed baths and skin care as necessary

b. eye care if client has decreased LOC c. meticulous perineal care to prevent yeast infections d. for the initiation of a bowel regimen with stool softeners with expected bowel movements at

least every three days

Skin and Muscle Integrity 1. Prevent the effects of immobility by routine passive or active range of motion exercises or get

client OOB as tolerated 2. Minimize decubitus ulcers by avoidance of rubbing or massaging reddened areas 3. Reposition client every hour if bed ridden

Safety

1. Apply bilateral splints as ordered to prevent footdrop and wristdrop 2. Provide a safe environment - bed in low position, side rails up, call light within reach 3. Initiate seizure precautions if indicated

Sensory Stimulation 1. Provide appropriate stimulation which means to schedule groups of tasks to prevent

overstimulation 2. Talk to clients before and during procedures or when any direct care or when in the room for other

reasons 3. Explain procedures before beginning them 4. Encourage family members to talk with clients about usual family activities 5. Enhance stimulation by

a. insertion of hearing aids b. a check of glasses for cloudy smeared lens then clean and put them nearby or on client c. a change of lighting in the room to mimic natural light changes d. promotion of the use of electronic battery devices such as CD – DVD – MP3 players, radio,

television. Have maintenance check for leakage of currents before use.

C. Myasthenia gravis (MG) 1. Definition

a. antibodies destroy acetylcholine receptors where nerves join muscles - myoneural junction

b. two age clusters: women in early adulthood and men in late adulthood

c. progressive with occurances of crises

2. Findings a. progressive fatigue or weakness of voluntary muscles, but

no muscular atrophy b. sensation remains intact c. facial

i. ptosis (drooping eyelid) and reduced eye closure ii. weak smile iii. diplopia, blurred vision iv. speech and swallowing disorders v. weakness of facial muscles - difficulty to raise

eyebrows, make different faces d. signs of restrictive lung disease

3. Diagnostics a. history and physical exam b. edrophonium (tensilon) test: improved muscle strength

after tensilon injection indicates a positive test for MG 4. Management

a. expected outcomes: to improve strength and endurance b. pharmacologic

i. anticholinesterase agents: pyridostigmine (mestinon), neostigmine (prostigmin)

ii. corticosteroid therapy iii. immunosuppressants: azathioprine (imuran)

c. thymectomy

d. plasma exchange e. myasthenic crisis management

i. crisis usually follows stressor or during dosage changes usually when being increased

ii. signs: sudden inability to swallow, speak, or maintain patent airway

iii. cholinergic crisis may follow over dosage of medication

iv. positive edrophonium (tensilon) test signals myasthenia

v. if negative endophronium test, client has not myasthenic but cholinergic crisis, so treat with atropine

vi. ventilatory support as indicated 5. Nursing interventions

a. identify aggravating factors, such as: i. infection ii. stress iii. changes in medication regime - especially when

increasing dose b. if client is in crisis: provide care of the client on ventilatory

support  c. give medications as ordered and on time d. help with ADL and feeding as indicated e. provide

i. emotional support ii. adequate rest periods iii. care of the post-surgical client

f. teach client i. energy conservation techniques ii. expectations, side effects and medications iii. signs of impending crisis, both myasthenic and

cholinergic along with what actions to take iv. to avoid stressors or how to minimize stressors

VI. Seizure Disorders A. Definition/etiology

1. Sudden, transient alteration in brain function 2. Disorderly transmission of electrical activity in the brain 3. Causes

a. cerebral lesions b. biochemical alteration c. cerebral trauma d. idiopathic

B. A classification of seizure types:  partial, simple, complex, generalized

1. Partial seizures a. focal motor b. seizure activity only in specific parts of the brain c. usually client remains conscious

2. Simple with findings associated with a. motor activity b. special sensory feelings c. autonomic activity d. psychic issues e. psychomotor actions f. no loss of consciousness

3. Complex a. impairment of consciousness b. secondarily generalized c. progressing to generalized tonic-clonic

4. Generalized seizures: eight types a. petit mal - called absence seizures b. myoclonic

i. sudden, uncontrollable jerking movements of one or more extremities

ii. usually occurs in the morning c. clonic

i. characterized by violent bilateral muscle movements

ii. hyperventilation iii. face contortion iv. excessive salivation v. diaphoresis vi. tachycardia

d. tonic i. first, client loses consciousness suddenly and

muscles contract bilaterally ii. body stiffens in opisthotonos position

SEIZURE CLASSIFICATIONS

A. Types of generalized seizures - one classification system 1. Absence seizures (petit mal seizures) 2. Myoclonic seizures (bilateral massive epileptic myoclonus) 3. Generalized tonic-clonic seizures (grand mal seizures) 4. Akinetic seizure

B. Proposed international classification of epilepsies and epileptic syndromes 1. Idiopathic 2. Benign childhood epilepsy 3. Primary reading epilepsy 4. Symptomatic

a. chronic progressive epilepsia partialis continua of childhood b. syndromes characterized by seizures with specific triggers

5. Cryptogenic a. presumed to be symptomatic but etiology is unknown b. differs from Symptomatic by lack of etiologic evidence

iii. jaws clenched iv. may lose bladder control v. apnea with cyanosis vi. pupils dilated and unresponsive vii. usually lasts less than a minute

e. grand mal: most common type i. tonic-clonic movements bilaterally ii. may be preceded by prodromal iii. lasts two to three minutes iv. often incontinent of bowel/bladder v. after clonic phase, client is unresponsive for about

five minutes vi. arms and legs go limp vii. breathing returns to normal viii. possible disorientation or confusion for sometime

afterwards ix. possible headache and fatigue afterwards

f. atonic: sudden loss of postural muscle tone with collapse g. unclassified seizures h. status epilepticus

i. rapid sequence of seizures without interruption or pauses

ii. medical and nursing emergency iii. client in postictal state when next seizure begins iv. sometimes occurs if a sudden stop of maintenance

anticonvulsants v. if cerebral anoxia occurs, brain damage or death

can follow vi. risk for severe organ and muscle hypoxia

5. Diagnostics a. by the event itself - see above b. history and physical exam c. electroencephalogram (EEG)d. computerized tomogram (CT) scan

6. Management a. expected outcomes: to control or minimize the seizure

activity and prevent complications b. correction of underlying problem c. medications

i. benzodiazepines, I.V. such as diazepam (valium), lorazepam (ativan) for active seizures

ii. hydantoin anticonvulsants such as phenytoin (dilantin) - maintenance

iii. barbiturates such as phenobarbitol - maintenance iv. succinimides such as ethosuximide (zarontin) -

maintenance 7. Nursing interventions

a. administer medications as ordered b. seizure care  c. seizure precautions  d. teach client

i. to wear MedicAlert jewelry ii. about medication effects, interactions, and side

effects iii. to learn when a seizure may be triggered iv. techniques to reduce stress v. seizure care at home or at work

vi. if in public area, after the tonic phase turn client to side

VII. Headache A. Definition

1. Pain located in the upper region of the head 2. One of the most common neurologic complaints

B. Classifications 1. Recurrent migraine headache

a. onset during adolescence or early adulthood b. familial c. involves unilateral, throbbing pain d. subtypes

i. classic migraine ii. common migraine iii. cluster headache iv. hemiplegic headache v. ophthalmoplegic headache

2. Recurrent muscular-contraction headache (pressure, tension headache)

a. most common form of headache b. may be direct result of stress, anxiety, depression, drastic

changes in caffeine consumption 3. Nonrecurrent headaches

a. occur with systemic infections and are usually associated with fever

b. occur as the result of a lesion, after an invasive spinal cord procedure such as a lumbar puncture, or subarachnoid bleed

c. caused by increased intracranial pressure C. Findings

1. Vary by type of headache 2. May include throbbing, nausea, vomiting, visual disturbance,

tenderness, neck stiffness, and focal neurological signs

SEIZURE CARE

1. Do not leave the client who is seizing 2. Attempt to prevent or break client's fall by assisting him/her to horizontal position on the bed

or the floor 3. Loosen tight clothing around neck and chest 4. Remove objects near the client 5. Place a pillow under the client's head if possible and available 6. Place the client's head in a lateral position if possible to maintain airway 7. Place nothing in the client's mouth 8. Cover the client if possible 9. Document

a. type of seizure - describe behavior rather than labeling b. duration c. activity during and if incontinence d. if any precipitating factors e. client's response - immediate, then at 15 minute intervals until stability is established

D. Diagnostics 1. History and physical exam 2. Computing tomogram (CT) scan 3. Magnetic resonance imaging (MRI)

E. Management of headaches 1. Expected outcomes: to alleviate pain and treat underlying cause 2. Vasoconstriction by pressure or cold 3. Management of migraine

a. nonnarcotic analgesics usually when onset noted: aspirin, acetaminophen (Tylenol), ibuprofen

b. narcotic analgesics: codeine, meperidine (Demerol), morphine

c. alpha-adrenergic blocking agentblocker: ergotamine tartrate (Ergostat) without or with caffeine

d. steroids: dexamethasone (Decadron) e. prophylactic treatment with beta-adrenergic blocking

agents, serotonin antagonists, antidepressants, imipramine (Tofranil)

f. avoid headache-precipitating foods such as MSG, tyramine, or milk products, or sudden stopping of caffeinated drinks

4. Management of cluster headaches - a type of migraine a. narcotic analgesics: codeine sulfate b. alpha-adrenergic blocking agentblocker: ergotamine

tartrate (Ergostat) c. prophylactically with serotonin antagonists

5. Management of tension headaches a. nonnarcotic analgesics b. muscle relaxants c. prophylactically: antidepressants and/or doxepin

(Sinequan)F. Nursing interventions

1. Suggest a quiet, dark environment 2. Manage pain by prompt medication administration or other

comfort measures 3. Help client identify precipitating factors and actions for prevention 4. Keep NPO until nausea and vomiting subside 5. Teach client

a. to keep a headache diary b. expected medication actions and side effects c. alternatives for pain relief including referrals for alternative

approaches d. to avoid or minimize trigger factors

VIII. Head Trauma

A. Classifications 1. Closed versus open injury

a. closed is nonpenetrating; no break in the integrity of the skull

b. open injury: skull is broken with the brain exposed 2. Severity

a. mild: only momentary loss of consciousness with no neurological sequelae

b. moderate: momentary loss of consciousness with a change afterwards in neurological function which is usually not permanent

c. severe: decreased LOC with serious neurological impairment and sequelae

B. Types of skull fractures 1. Linear: simple break in the bone; no displacement of the skull 2. Depressed: part of skull is pushed in 3. Basilar: at base of skull; may extend into orbit or ear; ear or nose

may leak CSF; most difficult to verify by x-ray 4. Concussion: temporary loss of neurologic function with complete

recovery C. Types of bleeding or hematomas

1. Epidural a. usually something lacerates the blood vessels (arteries) of

the middle meninges b. since this is arterial bleeding, the risk of death is greatest c. client commonly looses consciousness after injury then is

lucid; then LOC drops quickly with the next 24 hours 2. Subdural

a. something has lacerated the blood vessels (veins) crossing the subdural space

b. acute: findings surface in 24 to 72 hours after injury with rapid neurologic deterioration

c. subacute: findings surface 72 hours to 2 weeks after injury with a slower progression of deterioration

d. chronic: gradual clot formation over time, possibly months with minimal deterioration

D. Progression of skull fracture injury 1. Onset: contusions and lacerations of nerve cells 2. Neuron death: gradual demyelinization of affected nerve fibers 3. Scarring: meninges adheres to injured area of brain

E. Complications 1. Cerebral edema

a. results in increased intracranial pressure b. results directly from cerebral ischemia, anoxia, and

hypercapnia 2. Diabetes insipidus (DI)

a. DI results from a decrease release of antidiuretic hormone (ADH) and body excretes too much fluid

b. the increase in urinary output results in a low specific gravity

c. more common in the initial acute phase of head injury 3. Stress ulcer

a. head injuries activate both the sympathetic and parasympathetic systems

b. stimulation of sympathetic system leads to gastric ischemia from vasoconstriction

c. stimulation of parasympathetic system leads to increased release of hydrochloric acid (HCL) into the stomach

d. steroid therapy may contribute to the development of ulcers since steroids increase HCL acid

4. Syndrome of inappropriate anitdiuretic hormone (SIADH) a. too much ADH is produced b. water is excessively retained - hemodilution c. urinary output decreases; urine specific granity increases

effect d. more common in the chronic phase of care after a head

injury 5. Seizure disorders 6. Infection: brain, lungs, urinary system from immobility 7. Hyperthermia or hypothermia

F. Findings of head trauma 1. Degree of neurological damage varies with type and location of

injury 2. Restlessness and irritability - initially 3. Decreased LOC - lethargy, difficulty with arousal 4. Headache 5. Nausea and vomiting - projectile vomiting indicates increased ICP

G. Diagnostics 1. History and physical exam 2. Computerized tomogram (CT) scan 3. Magnetic resonance imaging (MRI) 4. Electroencephalogram (EEG)

H. Management 1. Expected outcomes: to reduce or minimize increases in

intracranial pressure and protect the nervous system 2. Medications for increased ICP

a. osmotic diuretics; mannitol (osmitrol) - IV drip or push b. steroids: dexamethasone (decadron) - IV push c. barbiturate coma may be induced to treat refractory

increased intracranial pressure 3. Surgical correction of underlying cause 4. Treatment for evident findings: seizures, fever, infection 5. Therapy

a. nutritional support b. physical c. speech d. behavioral e. occupational

I. Nursing interventions 1. Provide care of the client with increased intracranial pressure 

a. seizure precautions  b. seizure care  c. care of the client on ventilator  d. care of the client undergoing surgery

2. Monitor for balanced nutrition and fluids 3. Assist with ADL as indicated 4. Prevent complications of immobility 5. Monitor neuro vital signs 6. Give medications as ordered 7. Provide emotional support with appropriate referrals 8. Manage pain within agency's guidelines

IX. Brain Tumors A. Growth of tissue within the brain tissue enclosed by the skull

1. May be cancerous or benign 2. Classified according to tissue type 3. May be primary or metastatic

B. Findings 1. Depend on the size and the location of tumor 2. Locations and findings

a. frontal lobe: personality changes - classic, focal seizures, visual disturbances, hemiparesis, aphasia

b. occipital lobe: visual hallucinations, focal seizures c. temporal lobe: headache, seizures d. parietal lobe: visual losses, seizures e. cerebellum: coordination or mobility difficulties

3. Increased intracranial pressure as tumor enlarges C. Diagnostics

1. History and physical exam 2. CT scan 3. Magnetic resonance imaging (MRI)

D. Management 1. Expected outcome: removal of the tumor with minimal harm to the

nervous system 2. Depends on the location and size of the tumor 3. Treatment for associated increased intracranial pressure from

tumors a. surgery b. craniotomy to remove tumor c. stereotactic laser surgery d. radiation therapy for malignancy

4. Medications for malignant tumors: chemotherapy E. Nursing interventions

1. Provide: a. care of the client with increased intracranial pressure from

tumors  b. care of the client undergoing

I. surgery II. radiation therapy

III. chemotherapy c. seizure precautions  d. seizure care  e. balanced nutrition and fluid

2. Facilitate emotional support with referrals to support groups for the client and family

X. Peripheral Nerve and Cranial Nerve Disorders A. Trigeminal neuralgia (tic douloureux)

1. Syndrome of paroxysmal facial pain a. occurs more often in middle age and older adults b. affects cranial nerve five (trigeminal nerve) c. has unknown etiology d. involves one side only e. is triggered by harmless events such as a breeze, hot or

cold liquids 2. Findings

a. intense facial pain lasting about one to two minutes along the nerve branches

b. extreme facial sensitivity c. pain may be described as "burning" or "shooting"

3. Diagnostics: history and physical exam4. Management

a. expected outcomes: to relieve pain and to minimize frequency

b. anticonvulsants: carbamazepine (tegretol), phenytoin (dilantin)

c. surgery I. minor

I. radio-frequency gangliolysis: heat destroys trigeminal ganglion

II. glycerol gangliolysis: glycerol injected into subarachnoid space around gasserian ganglion

II. major - microvascular compression: move arterial loop away from posterior trigeminal root

5. Nursing interventions a. help clients to name trigger points with identification of

triggering incidents b. recommend restful environment with scheduled rest

periods c. reinforce the need for balanced nutrition d. provide appropriate care of the client undergoing surgery e. teach client

I. about medications and side effects II. to avoid triggering agents

III. to chew on the opposite side of the mouth IV. to avoid drafts V. to avoid very hot or cold foods or fluids

B. Facial nerve paralysis (bell's palsy) 1. Definition/etiology

a. is a disorder of cranial nerve seven (facial nerve) b. involves one side only; unilateral c. has an unknown etiology d. often occurs during periods of high stress

2. Findings often occur suddenly over ten to 30 minutes a. ptosis b. cannot close or blink eye with excessive tearing c. flat nasolabial fold d. impaired taste e. lower face paralysis f. difficulty eating - impaired mastication of food and difficulty

swallowing 3. Diagnostics: history and physical exam 4. Management

a. expected outcome: to restore cranial nerve function b. medications

I. prednisone II. analgesics

c. local comfort measures: heat, massage and electrical nerve stimulation for muscle tone

d. alternative therapies: reiki, massage, imagery5. Nursing interventions

a. reinforce balanced nutrition with a soft diet b. administer drugs as ordered c. teach client

I. to chew on the opposite side II. how to use protective eye wear during risk periods -

patch or glasses over eye III. effects of steroids

IV. the use of eye drugs or ointment to protect the eye from corneal irritation

V. that once findings disappear their return may occur especially in times of high stress

XI. Senses: Eye and Ear I. Eye structures

A. Three layers of the eye: sclera, choroid, and retina 1. Sclera: maintains eye shape 2. Choroid: packed with blood vessels and pigmented to

absorb light and prevent blurring of an image a. choroid forms iris and lens in front b. Schlemm's canal (venous sinus) circles where

cornea and iris meet; iris gives eye its color c. muscles of iris adjust pupil d. pupil adjusts to

i. protect retina ii. allow enough light to stimulate retina

Points to Remember In multiple sclerosis, early changes tend to be in vision and motor sensation; late changes tend to

be in cognition and bowel control. Peripheral nerves can regenerate. However, nerves in the spinal cord are thought to not be able to

regenerate. During a seizure, do not force anything into the client's mouth or attempt to suction the mouth. A major problem often associated with a left-sided brain infarction (CVA) is an alteration in

communication. Clients with CVAs are at a greater risk for aspiration. Initially these clients must be evaluated to

determine if dysphagia is present. Changes in a client's respirations (rate, rhythm and depth) are more sensitive indicators of

increases in intracranial pressure than blood pressure and pulse. When caring for a comatose client, remember that the hearing is the last sense to be lost. Clients after a CVA often have a loss of memory, emotional lability and a decreased attention

span. Communication difficulties of a client with a CVA usually indicate involvement of the dominant

hemisphere, usually the left brain, and is associated with right sided hemiplegia or hemiparesis. The client with myasthenia gravis will have more severe muscle weakness in the evening due to

the fact that muscles weaken with activity - described as progressive muscle weakness - and clients usually regain strength with rest.

iii. improve depth perception iv. respond to sympathetic nervous system

with dilation e. ciliary body (smooth muscle) contracts to reduce

tension of suspensory ligament on the lens f. lens converges light onto the retina

3. Retina: inner, posterior layer that is photosensitive

a. consists of four layers i. pigmented epithelial cell ii. photoreceptor cells (rods and cones) iii. bipolar neuron iv. ganglion neuron

b. optic disk: retinal area of optic disk contains no photoreceptors (blind spot)

c. photoreceptor cells: turn light into nerve impulses to optic nerve, cranial nerve II

i. rods: located more peripherally - around edges of retina

I. black, white, gray vision II. peripheral vision

ii. cones: located in fovea centralis I. three types: red, green, and blue

receptors II. fine discrimination and color vision

B. Optic nerve, cranial nerve II 1. Nerve fibers from median half of each retina cross at chiasm and

travel to opposite sides of the brain 2. Nerve fibers from lateral halves of retina remain uncrossed

C. Chambers 1. Anterior chamber (locus of intraocular pressure [IOP]) 2. Posterior chamber 

D. Vitreous body E. Lens

1. Separates the posterior chamber from the vitreous body 2. Are transparent 3. Are held in position by suspensory ligaments attached to the

ciliary body F. Accessory structures

1. Protective structures: sockets, eyelids, eyelashes, eyebrows, conjunctiva

2. Lacrimal duct: secretes and drains fluid that moistens and lubricates the front surface of the eye; with decreased blinking less secretions result with complaints of "dry" or maybe "itchy" eyes

3. Six oculomotor muscles surround and enter the eyeball

EYE STRUCTURESA. Chambers

1. Anterior chamber filled with aqueous humor a. Secreted near ciliary body b. Circulates through suspensory ligament and pupil and under cornea c. Exits through the canal of Schlemm d. Enhances light refraction e. Cleans and nourishes the eye structures f. Determines intraocular pressure: Normal 16-30 mm Hg

2. Posterior chamber a. Narrow passage behind the iris b. In front of the lens and the ciliary body

B. Vitreous body 1. Filled with vitreous humor 2. Holds the retina in place

C. Optic nerve 1. Nerves from each eye meet at the optic chiasm 2. Nerve fibers from median half of each retina cross at chiasm and travel to

opposite sides of the brain 3. Nerve fibers from lateral halves of the retina remain uncrossed

II. Eye Functions A. Light reception

1. Light passes through the cornea, aqueous humor, lens, and vitreous body to the retina

2. The density of the cornea slows the light, and the curvature of the cornea bends the light (called refraction)

3. The lens further bends and redirects the light to a point on the retina

4. At this point, the light stimulates photoreceptor cells (rods, cones) which transmit electrical impulses

5. These impulses travel through the optic nerve to the brain B. Accommodation - decreases with aging and the loss begins int the 40 to

50 year olds 1. Process by which the lens changes shape to view an object at

close range (or long range) 2. Proper vision requires three processes:

a. convergence: image of the object falls exactly on the fovea centralis retinae of both eyes

b. focus: focusing of the lens (ciliary body [ciliary muscles] to contract or relax)

c. light regulations constriction or relaxation of the pupils to regulate light and to clarify the image on the retina

3. When muscles that carry out these three processes are weak or paralyzed the finding is called strabismus

C. Binocular vision 1. Allows the brain to judge distance 2. Brain judges

a. the difference between two images b. the amount of retina taken up by the image c. the difference between familiar and unfamiliar objects

(example: person standing next to an elephant) d. the different shades of color

3. Both eyes must move together for clear focus (called conjugate eye movements). Thus, to immobilize one eye, both eyes must be covered

III. Disorders of the Eye

Overview and content: eye disorders from the front to the back of the eye

Eye disorders from most common to least common

A. Disorders of refraction 1. Myopia (near-sightedness) - blurred distance vision, but clear

close vision 2. Hyperopia (far-sightedness) - blurred close vision, but clear distant

vision 3. Presbyopia - in middle age, lens loses elasticity with results of

hyperopia 4. Astigmatism - lens refracts light rays to focus on two different

points of retina B. Eye trauma care

1. Foreign body 1. use eversion procedure 2. if foreign body has penetrated, do not remove the foreign

body 3. irrigate affected eye with sterile normal saline eye irrigant

2. Corneal abrasion 1. disruption of the cells and loss of superficial epithelium 2. caused by trauma, chemical irritant, foreign body, or lack of

moisture 3. findings: severe pain, blurred vision, halo around lights,

lacrimation, inability to open eye, photophobia 4. diagnosis by fluorescein sodium dye 5. abrasions heal usually within 48 hours with no scarring or

visual deficit 6. treatment includes short-acting analgesic drops, eye rest

with soft or rigid eye patch 3. Corneal laceration

1. same causes and findings as with abrasions 2. lacerations are serious emergencies to require immediate

attention 3. surgery is generally required 4. follow care for client undergoing eye surgery (see points to

remember at the end of this section) 4. Penetrating injury

1. immediate care 1. do not remove the object 2. do not apply pressure of any kind to the eye or the

object 3. cover the injured eye to protect movement of the

object. may use a paper or plastic cup or rigid eye patch

4. cover uninjured eye with soft or rigid eye patch to avoid sympathetic movement

2. get client to emergency room immediately 3. surgery will be required

5. Chemical irritants 1. flush eye with plenty of tap water or sterile normal saline if

available 2. get client to emergency room immediately 3. alkaline substances penetrate the cornea rapidly and must

be removed quickly; these injuries are a priority to care for 4. acids coagulate the eye's proteins and often result in

relatively superficial, reversible damage 6. Ultraviolet burns

1. often occur from sun exposure or welding flashes – looking at a welding flame without special glasses during the welding process

2. irritate epithelium, which swells and scales off (desquamation)

3. care is the same as with lacerations 7. General pharmacotherapy for eye trauma

1. topical anesthetics 2. topical anti-inflammatory 3. topical mydriatic-cycloplegic agents to prevent papillary

constriction 8. General management of any eye trauma

1. do copious irrigation of the affected eye 2. apply bilateral rigid or soft eye patches to rest both eyes by

decreased eye movement 3. have clients use tinted glasses for photophobia to reduce

eye discomfort from artificial lights or sunlight 4. assist clients with activities of daily living as needed 5. review with clients to avoid activities which increase IOP

C. Glaucoma - the second most common cause of vision loss in the USA; may be unilateral or bilateral

1. Most common type: chronic open-angle glaucoma (simple, adult primary, primary open-angle)

1. etiology/epidemiology 1. hereditary link 2. unknown etiology 3. aqueous humor does not drain adequately which

leads to increased intraocular pressure (IOP) 4. this pressure on optic nerve causes destruction of

nerve fibers in the retina to result in a vision loss 2. findings

1. most clients are without findings until there is a loss of vision

2. peripheral vision loss is affected first prior to total loss of vision

3. three classic assessment findings 1. visual field loss  (peripheral) 2. elevated IOP

3. cupping of the optic disk

3. diagnostics

d. management i. expected outcomes - reduction of IOP and

prevention of visual field defects ii. treatment of choice: pharmacotherapy

miotic eyedrops (parasympathomimetic agents)

carbonic anhydrase inhibitors - Diamox beta-adrenergic blocking agents - Timoptic

drops epinephrine eyedrops (contraindicated in

clients with cardiac conditions) - used more often in emergency care

iii. trabeculectomy or laser trabeculectomy performed when pharmacological agents

are not effective small piece of sclera containing the

trabecular network is removed and an iridectomy is performed

cycloplegic and steroids eye drops are usually used

antibiotics may be ordered

Diagnostic Eye Tests A. Electroretinography

1. Detects diseases of the rods and the cones 2. Evaluates the electrical potential between the retina and the cornea 3. Method: electrodes incorporated into contact lenses are used to measure the

changes in the wavelength and intensity of light and for the state of adaptation of the eye

B. Tonography 1. Indirect measurement of intraocular pressure (IOP) 2. Used to detect glaucoma

C. Intravenous fluorescein angiography 1. Records the appearance of blood vessels within the eye 2. Used to evaluate for retinopathy and tumors 3. A contrast dye is injected intravenously and numerous photographs are taken of the

fundus oculi 4. Check client for sensitivity or allergy to fluorescein dye prior to the test 5. Mydriatic drops are used to dilate pupil

D. Ocular ultrasonography 1. Use of high frequency sound waves to evaluate eye structures 2. Particularly useful when eye is clouded with an opaque medium such as a cataract or

hemorrhage E. Electronystagmogram: record of electrical activity of eye during spontaneous, positional and calorically-invoked nystagmus

A. General nursing interventions in electrodiagnostic studies A. always explain test to client B. client must remain still during test unless instructed to do otherwise C. client should avoid stimulants before test

a mydriatic eye drop medication is then used to prevent adhesions to the cornea; remember that use of this classification of medications is contraindicated with glaucoma

e. nursing interventions i. for pharmacotherapy management

reinforce the need for compliance with medical treatment

teach client how to instill eye drops and when - usual recommended time is before bedtime

teach the need to reduce or eliminate safety risks related to impaired vision

ii. for trabeculectomy by traditional surgery monitor dressing for excessive bleeding administer antiemetics, analgesics,

mydriatics and antibiotics as ordered assist the clients with ADL as needed

iii. for trabeculectomy by laser surgery discuss that vision may be blurred for first

day or two post-op teach to use soft or rigid eye patches or

sunglasses for photophobia discuss the use of analgesics as ordered

iv. general education for clients with glaucoma stress the need to avoid activities that

increase IOP - bending, stooping, straining, coughing, blowing nose, laughing

stress the importance of routine eye exams- usually yearly or more often if complications or noncompliance with medication regimen

2. Less common type: acute closed-angle glaucoma (shallow, narrow-angle, or congested glaucoma)

a. etiology /epidemiology i. a medical and nursing emergency ii. iris lies near drainage channel (canal of Schlemm)

and bulges forward against cornea, blocking the trabecular network with the result of increasing IOP

iii. affects more women; usually after age of 45 b. findings

i. sudden onset of blurred vision, halos or colored rings around white lights

ii. sudden frontal headache iii. sudden severe eye pain, reddening of the eye,

nausea, vomiting iv. followed by progression of findings as the pressure

increases profuse lacrimation mildly dilated, nonreactive pupil more severe nausea/vomiting cornea appears hazy

v. blindness may result in two to five days if left untreated

c. diagnostics i. history of findings ii. ocular pressure readings

d. management i. expected outcome: to prevent or minimize the

damaging effects of acute closed-angle glaucoma

ii. emergency pharmacologic treatment to decrease IOP

intravenous osmotic agents topical miotic eye drops systemic carbonic anhydrase inhibitors systemic analgesics

iii. surgery iridotomy or iridectomy procedure is usually then repeated on the

unaffected eye e. nursing interventions

i. monitor for effectiveness of medications as ordered ii. apply eyepatch or sunglasses for post-op

photophobia iii. discuss with clients that vision is more often blurred

for one to two days postsurgery iv. stress the importance of routine yearly or more

frequent eye examinations v. teach clients to avoid activities that increase IOP

D. Cataract 1. Etiology

a. clouding of lens - may be unilateral or bilateral; one of the most common eye disorders

b. first type: senile cataract - result of aging process c. second type: traumatic

i. develops within a few months after eye trauma ii. painless but progressive loss of sight in one or both

eyes 2. Findings

vision becoming clouded, blurred or dim Sensitivity to light and glare Halos around lights Fading or yellowing of colors Double vision or multiple vision in one eye You might find it harder to see at night

3. Diagnostics a. history b. physical exam of eyes

4. Management a. expected outcome: correction of visual field defect b. treatment: only surgical

i. cataract extraction: removal of cloudy lens most commonly done as an outpatient

procedure usually done on one eye at a time types of cataract extractions

o extracapsular cataract extraction (ECCE)

procedure of choice lens contents removed and

the posterior chamber is left intact

o phacoemulsification – ultrasound fragments of the lens contents

o intracapsular cataract extraction (ICCE)

the lens contents and lens capsule are removed

eye becomes hypermetropic c. intraocular lens implant is usually performed at the time of

the extraction

d. peripheral iridectomy is usually performed as part of an ECCE or ICCE

5. Potential post-surgical complications a. hyphema (blood collects in the anterior chamber of the

eye) i. may require bed rest and eye patching ii. observe for increased IOP - indicated by complaints

of severe pain iii. may have prescribed miotics or cycloplegics

b. vitreous prolapse i. allows vitreous humor to fall forward into wound ii. may result in pupil function blocked iii. may lead to retinal detachment iv. vitrectomy may be performed

c. intraocular infection i. complaints of throbbing or pain with cloudy

drainage from the eye ii. antibiotics (ophthalmic and/or systemic)

6. Nursing interventions a. teach client to avoid actions that cause IOP b. observe clients' ability to instill eyedrops correctly; provide

referrals if clients unable to do so c. provide written list for findings of complications to report d. inform clients

i. an expected, normal feeling after cataract surgery is that "sand" is in the eye for six to eight weeks afterwards

ii. photophobia, that may be present for months to years, simply requires the use of sunglasses in bright light

E. Retinal detachment

1. Etiology/epidemiology a. holes or breaks (tears) in the retina b. fluid, blood or a mass separates the retina's sensory layer

from the pigmented epithelium (pigment cells) c. common causes are inflammation, trauma, hemorrhage,

and tumors d. retinal detachment often begins in the periphery and

spreads posteriorly 2. Findings

a. a rapid separation gives the sense of a "curtain being pulled over the eye" so that clients have partial vision in affected eye

b. a slow separation may be asymptomatic c. the ophthalmic exam reveals the detached area as gray

bulge, ripple or fold 3. Diagnostics

a. history b. physical inspection

4. Management a. expected outcome: correction of and/or prevention of

further vision loss: 90% are successfully repaired b. laser surgery

i. photocoagulation: laser beam is directed through a dilated pupil

ii. the effect is to seal localized breaks or rips in the retina

c. cryotherapy: extreme cold freezes rips in the retina d. diathermy: heat is applied with ultrasonic probe to repair

rips e. scleral buckle f. pharmacotherapy: local or systemic

i. adrenergic-mydriatic agents ii. cycloplegic agents iii. antibiotics

5. Nursing interventions a. maintain the client in proper position for bed or chair rest

as ordered b. apply a post-op rigid/soft eye patch to rest eye (or both

eyes) c. suggest dark lens glasses for photophobia d. administer medications as ordered e. prevent activities that increase IOP

F. Visual impairment and blindness 1. Legal blindness: a maximum visual acuity of 20/200 (with optimum

correction) and/or a visual field that is reduced to a range of 20 degrees (normal range: 180 degrees)

2. Most common causes: retinal degeneration, glaucoma, cataract, amblyopia, macular degeneration - called "central" loss of vision

3. Nursing interventions a. speak to clients upon entering the room b. implement safety measures based on how clients

accomodate the loss of sight c. orient clients to new surroundings; use numbers on

traditional clock for the placement of furniture or food on plates

d. assist clients with activities of daily living as needed e. for walking, do not take clients' arm to lead. Offer clients

an arm so that the blind person holds the arm at the elbow of the lead person who walks a little in front of the blind person.

The Ear

I. Structures of Ear - note the pinna - this is what is pulled when ear drops are given

A. External auditory meatus B. Middle ear

1. Tiny, air-filled cavity containing three small bones: incus (anvil), malleus (hammer) and stapes (stirrup)

2. These bones (ossicles) are connected by joints and supported by muscles

3. Ossicles bridge the tympanic membrane and the oval window 4. Ossicles magnify small sounds by transmittting them from the

tympanic membrane to the oval window. C. Inner ear

1. General I. Contains the sensory receptors for sound and equilibrium

II. is connected to nasopharynx by the eustachian tube

Diagnostic1. Electrocochleogram

a. measures auditory function b. nursing intervention: be aware that client may experience vertigo c. assure client safety

2. General nursing interventions in electrodiagnostic studies a. always explain test to client b. client must remain still during test unless instructed to do otherwise c. client should avoid stimulants before test

III. the eustachian tube opens during swallowing to equalize inner ear pressure to the atmospheric pressure

IV. is composed of fluid-filled membranous labyrinth in a similarly shaped bony labyrinth

V. membranous labyrinth components include the cochlea and the vestibular apparatus

2. Cochlea: a spiral tube

I. within the cochlea is a membranous duct with a triangular cross section:

I. side one lies against wall of bony labyrinth II. side two is made up of Reissner's membrane

III. side three is Organ of Corti (basilar membrane) which contains the tectorial membrane, connected by hairs to sound-receptor cells

IV. hairs of receptors convert sound waves to neural impulses

V. impulses travel via the acoustic or eighth cranial nerve to the brain

II. vestibular apparatus: reflects body position

I. surrounded by perilymph and temporal bone II. consists of membranous saccule, utricle, and

semicircular canals III. in these canals, static and dynamic equilibrium

receptors send impulses to the brain regarding body position

II. Ear Disorders A. External ear

1. Swimmer's ear a. diffuse bacterial otitis externa

b. preventable by using 70% alcohol to cleanse ears after swimming

2. Otitis externa B. Middle ear: otitis media C. Inner ear: Meniere's disease

1. An inner ear disorder: the endolymphatic system dilates and the volume of endolymph expands

2. Etiology unknown a. usually develops between the ages of 40 and 60 b. acute attack may require hospitalization c. clients may average two to three attacks per year

3. Findings a. attacks intermittent b. three recurrent and progressive findings

i. vertigo with prostrating nausea and vomiting ii. tinnitus iii. hearing loss on involved side persists and

progresses 4. Diagnostics

a. history b. direct inspection

5. Management a. expected outcomes: prevention of hearing loss and control

of vertigo b. medical

i. cholinergic blocking agents such as atropine ii. antihistamines or decongestants iii. during remission

diuretics to decrease fluid accumulation vasodilators such as histamine vestibular suppressants such as diazepam

(valium) adrenergic neuron-blocking agents such as

epinephrine low-salt diet

c. surgical i. decompression of endolymphatic sac: insertion of

an endolymphatic subarachnoid shunt ii. labyrinthectomy: client will lose all hearing in

affected ear

5. Nursing interventions during an acute attack of Meniere's disease a. keep clients on bed rest in a quiet, dark room b. avoid unnecessary movement of clients especially of their

head c. give general care to clients with nausea and vomiting d. restrict salt and water intake as ordered e. have clients avoid tobacco, caffeine f. institute precautions to prevent clients from falling g. discuss the need to avoid a high triglyceride diet

D. Otosclerosis 1. A hereditary degenerative disorder that results in conduction

deafness 2. The formation of new bone growth in labyrinth adheres the stapes

to the oval window 3. Etiology unknown 4. Findings

a. hearing loss b. tinnitus

5. Diagnostics

a. bone conducts more sound than air does 6. Management

a. expected outcome: improvement of hearing in the affected ear

b. medical: use of a hearing aid c. surgical: stapedectomy - replacement of stapes with a

prosthesis 7. Postoperative care

a. teach clients to avoid anything that might displace prosthesis, such as coughing, blowing nose, swimming

b. limit activity as ordered and as tolerated c. give medications as ordered: antiemetics, analgesics,

antibiotics d. assess facial nerve function for asymmetry e. keep external ear area dry f. instruct client not to fly for at least six months

Points to Remember

Eye Anything that dilates the pupil obstructs the canal of Schlemm and increases

intraocular pressure. Color blindness is caused by a deficiency in one or more types of cones and is

caused by a sex-linked recessive gene. Destruction of either the right or left optic nerve tract results in blindness in the

respective side of both eyes When mydriatics are instilled and the pupils have been dilated, caution clients

that vision will be blurred and they will have photophobia for one to two hours After eye surgery teach clients to avoid activities that can increase IOP for six

weeks Stooping Bending from the waist Heavy lifting Excessive fluid intake Emotional upsets - crying, laughing Constrictive clothing around neck Straining during bowel movement (i.e., straining at stool) Sustained coughing or blowing of the nose

Teach clients proper administration of eyedrops; most importantly to wash their hands before drop installation

Advise the use of sunglasses for photophobia Assist with activities of daily living as needed When clients wear one eye patch, they lose their depth perception. Remember

that this loss presents a safety risk during mobility or cooking activities. Systemic disorders that can change ocular status include diabetes mellitus,

atherosclerosis, Graves' disease (hyperthyroidism), AIDS, leukemia, lupus erythematosus, rheumatoid arthritis sickle cell disease.

If there is some problem with the pigments in the cones, the eye will not see colors in the usual way. This is called color deficiency or color blindness.

If just one pigment is missing, the eye might have trouble seeing certain colors. Red-green colorblindness - where red and green might look the same - is the most common form of colorblindness, followed by blue-yellow colorblindness.

In some eyes, none of the pigments are present in the cones, so the eye does not see color at all. This most severe form is known as achromatopsia

Color blindness is a genetic condition that only rarely occurs in women, but affects about 1 out of every 10 men to some degree.

Ear

Changes in barometric pressure will affect persons with ear disorders to cause increased findings or malfunctions

Hearing loss can be partial or total affect one or both ears occur in low, medium or high frequencies

In the elderly the loss of high frequency sounds may require special smoke detectors with low frequency sounds

The American Medical Association formula for hearing loss: hearing is impaired 1.5% for every decibel that the pure tone average exceeds 25 decibels (dB)

A hearing loss of 22.5% usually affects social functionality and requires a hearing aid

Noise exposure is the major cause of hearing loss in the United States of America

Ask clients how they communicate: lip-reading, sign language, body gestures, or writing

To gain a client's attention, raise a hand or touch the client's arm When talking with clients who have a hearing loss, speak slowly and face them Speak toward the client's good ear If the client wears a hearing aid, allow him/her to show how it is inserted, turned

off/on, and cleaned Speaking louder to a hearing impaired clients does not increase their chances of

hearing Communicate about clients with a hearing loss to other staff members Ototoxic drugs include:

Aminoglycosides Antimyobacterials Thiazides Loop diuretics Antineoplastics

Tell clients taking ototoxic drugs to report any signs of dizziness, loss of balance, tinnitus, or hearing loss

Speak in lower tones to facilitate the hearing of clients over 50 years of age