Download Week 2 Lecture Notes File

NUR 611 HUMAN BIOSCIENCES: ALTERED BODY
FUNCTIONS
DISORDERS OF THE VISUAL AND AUDITORY
SYSTEMS
compiled by
Venina Navuta
23/1/17
DISORDERS OF THE AUDITORY SYSTEM
Diagnostic Tests
Laboratory tests
-routine blood tests
-Culture
-If clear fluid draining from ear,
rule out cerebrospinal fluid
Radiological tests
- Computed tomography (CT
scan)
- Magnetic resonance imaging
- Arteriography and venography
Special Tests
Auditory Acuity Tests – whispered
voice test, tuning fork tests, Rinne
test, Weber test.
Audiometric Hearing Tests
Balance Testing
Inspection and palpation only
Inspect mastoid process for
redness/swelling
External ear: inspected for shape,
location of attachment to the head and
condition of the visible external canal
Otoscope is used to visually see
and test the external ear canal
Consists of a light, a handle, a
magnifying lens and a bulb for
injecting air to test eardrum
mobility
Tympanic Membrane(TM)
Observations
- color, intactness and shape
Characteristics
shiny,
transparent and
opaque/pearly gray
slightly concave, movable, & free from
lesions
Visual Inspection
◦Pinna: swelling, nodules (gout/skin
cancer/rheumatoid arthritis) and lesions
(malignant skin cancer)
Otoscopic Examination
◦Tympanic Membrane: redness,
of infection
Completed after bilateral external ear and
otoscope examination
Sound is transmitted by both air
conduction and bone conduction
Air conduction of sound is normally more
sensitive than bone conduction
Voice Test
Watch Test
Tuning Fork Tests: useful,
although limited, in differentiating
between conductive and
sensorineural hearing losses
AUDIOMETRY
Measurement of hearing acuity
Hearing: measured in intensity of sound
expressed as decibels
Conversational speech is generally around 60
decibels
Hearing loss of 45-50 decibels – need a
hearing aid
Hearing loss of 90 decibels – may not be able
to hear speech – even with a hearing
aid
EAR INSPECTION
Normal external ear canal is free
from lesions, is dry, clean and not
reddened
Any deviation from the normal ear
shape and attachment is recorded
The nurse notes any drainage
Outer and Middle Ear Disorders
 Structural defects due to
embryologic malformations
 Structural changes
secondary to infection or
trauma
Outer Ear Disorders
• Microtia and atresia
Microtia: abnormal smallness of auricle
Atresia: absence of an opening of the
external ear
• Impacted cerumen: very common
cause of temporary conductive HL.
Very treatable and preventable. HL
that results is flat, conductive, and of
varying degree.
DISORDERS OF THE EXTERNAL EAR
Infections e.g. otitis externa
Masses e.g. cysts, malignant tumors
Foreign body
Impacted cerumen
Pruritis
Microtia and atresia(congenital)
EXTERNAL OTITIS
Allergic Reactions Pain
Itching
Bacterial/fungal
Infection
Hearing loss
Swimming
Plugged feeling in
ear
Trauma
Redness and edema
TREATMENT
Topical antibiotics
Corticosteroids
Oral analgesics
Local heat
DISORDERS OF THE MIDDLE EAR
Infections e.g. otitis media,
mastoiditis
Perforated tympanic
membrane
Otosclerosis
OTITIS MEDIA
Exudate, pain,
Bacterial or viral pressure
infection
Hearing
Fluid accumulation loss/Tinnitus
Fever/Malaise
Nausea/Vomiting
Bulging Tympanic
Membrane
TREATMENT
Systemic antibiotics
Analgesics/local heat
Antipyretics
Antihistamines
Decongestants
Myringotomy (surgical perforation of
eardrum – drains fluid/relieves pain
DISORDERS OF THE INNER EAR
Acoustic neuroma – benign
tumor of the 8th cranial nerve
-occurs at any age
-Common in women between
30-60 years.
MENIERE’S DISEASE
Occurs due the imbalance of
fluid and electrolytes in the
inner ear.
S/S – severe tinnitus,feelings
of ear fullness, vertigo
MENIERE’S DISEASE
Consists of three distinct characteristics:
1) Tinnitus
2) Unilateral sensorineural hearing loss
3) Vertigo
**Occurs in attacks that can last for several
days. Attacks render the client almost totally
incapacitated during attack and several days
are needed for full recovery
MENIERE’S DISEASE
Pathologic changes: either overproduction or
decreased reabsorption of endolymphatic fluid,
causing a distortion of the entire inner-canal
system
Distortion leads to decreased hearing from
dilation of the cochlear duct, vertigo because
of damage to the vestibular system, and
tinnitus from unknown cause
Usually occurs unilaterally
MENIERE’S DISEASE
Initial hearing loss is reversible
Repeated damage to the cochlea, caused by
increased fluid pressure, leads to permanent
hearing loss
Cause of disease unknown – but is associated
with viral or bacterial infections, allergic
reactions and biochemical disturbances that
increase
fluid imbalances
MENIERE’S DISEASE
Usually occurs between 20-50 years of age –
greater prevalence in men and Caucausians
Tinnitus is a continuous, low pitched roar or
humming sound, worsens just before and during
an attack
Hearing loss is worse during an attack –
permanent hearing loss develops as the
attacks increase
HEARING LOSS
Inability of the ear to detect
and perceive sound
3 main types: conductive,
sensorineural and mixed
CONDUCTIVE HEARING LOSS
 Can be caused by anything
that blocks the external
ear.
 Interference of conduction
of sound through the
external auditory canal,
eardrum or the middle ear
SENSORINEURAL LOSS
Occurs from a disease or
trauma to the inner ear,
neural structures or nerve
pathways leading to the
brainstem.
Cochlear Disorders
Syndromes and inherited
disorders
Noise induced hearing loss
Other trauma
Infections
Ototoxicity
Infections
Congenital
◦Cytomegalovirus
◦HIV
◦Rubella
◦Syphilis
◦Toxoplasmosis
Infections
Acquired
◦Herpes Zooster Oticus
(Chicken Pox)
◦Mumps
◦Syphilis
Ototoxicity
Some antibiotics that
Neomycin
are often ototoxic:
Amikacin
Netilmicin
Dihydrostreptomycin
Garamycin
Gentamicin
Kanamycin
Streptomycin
Tobramycin
Viomycin
Chemotherapy
Carboplatin
Cisplatin
Drugs that cause reversible hearing loss
Quinine
Salicylates
(aspirin)
Loop diuretics
Drugs that may be harmful during pregnancy
Accutane
Dilantin
Quinine
Thalidomide
Central Auditory Disorders
VIII
Nerve tumors
Other
diseases of the VIII Nerve
Neural disorders
Cochlear neuritis
Diabetes mellitus
Brain Stem disorders
Infarcts
Gliomas
Multiple sclerosis
Temporal
Lobe disorders
DISORDERS OF THE EYE
ACCESSORY ORGANS OF EYE
Eyebrow
Eyelids and eyelashes
Lacrimal apparatus
NURSING CONSIDERATION
preservation of vision
prevention of further visual loss in those
patients who have already experienced some
degree of loss.
maximal practical use should be sought for any
remaining vision
Skilful listening & interviewing are critical tools
for the rehabilitation of the distressed patient
Common eye diseases seen at the
CWMH :
-Pterygium
-Tarsal cyst
-Granuloma
-chalazion
THEATRE CASES
Cataract
-evisiation
-Enucleation
•Corneal perforation repair
•iridectomy
IMPORTANCE OF CLIENT HISTORY
Family history of eye problems (refractive
errors, night blindness, colorblindness)
Gender – retinal detachments are more
common in men and dry-eye symptoms are
more common in women
Age: incidence of glaucoma/cataract
formation increases with aging
Presbyopia (inability of the eye to read close
up, due to aging of the natural lens of the eye)
MEASUREMENT OF VISION
Visual acuity tests measure both distance and
near vision
Snellen Chart: tool to measure distance vision
Client stands 20 feet away from the chart,
covers one eye and uses other eye for
testing.e.g. 20/50 means that client is able to
see at 20 feet what a “healthy eye” can see at
50 feet
COMMON MEDICATIONS USED
Topical
anaesthetic
Mydriatic
Cyclopedic
agents
Anti-infective
Corticosteroids
NSAIDS
anti-allergy
Eye irrigant
lubricants
Eye Disorders
Refractive errors
Muscular disorders
Disorders of the eyelid
Disorders of the globe of the eye
Refractive Errors
Hyperopia
Myopia
Astigmatism
Presbyopia
Hyperopia (Farsightedness)
Mechanism
◦object focuses behind the retina
◦able to see only far objects
Etiology
◦genetic link
SYMPTOMS AND SIGNS
◦blurred vision
◦Squinting
◦eye rubbing
◦headaches
DIAGNOSIS
◦Snellen visual acuity test
◦ophthalmoscope
TREATMENT
◦Convex lens
Myopia (near sightedness)
Mechanism
◦object focuses in front of the retina
◦able to see only close objects
Etiology
◦genetic link
Symptoms and signs
◦blurred vision
◦Squinting
◦eye rubbing
Diagnosis
◦Snellen visual acuity test
◦opthalmoscope
Treatment
◦concave lens
◦radical keratotomy - shallow incision
in the cornea causing it to flatten in
desired area
(could have significant
complications)
Astigmatism
Mechanism
◦Abnormal shaped cornea
(egg shape instead of spherical)
◦object is partially clear & other
blurred
Etiology
◦genetic link
Symptoms and signs
oblurred vision
oSquinting
oeye rubbing
oheadaches
Diagnosis
◦Snellen visual acuity test
◦opthalmoscope
Treatment
◦artificial lens transplant
◦radial keratotomy
Presbyopia
Mechanism
* Rigidity of the lens (old age)
* unable to focus
Etiology
* genetic link
Old age (< 40 year)
Symptoms and signs
* blurred vision
* squinting
* eye rubbing
* headaches
Diagnosis
◦* Snellen visual acuity test
* opthalmoscope
Treatment
◦* lens transplant
Muscular Disorders
Nystagmus
Strabismus
Nystagmus
Mechanism
* repetitive involuntary movements of one or
both eyes
Etiology
* Congenital
* Brain tumors
* CV lesions
* Ear lesions
* Alcohol/drug abuse
Symptoms and signs
* Eye movements
*Horizontal, vertical, circular, or combination
* blurred vision
Diagnosis
* viewing of the eyes - involuntary movement
* complete neurological tests
Treatment
* Treat the underlying condition
* Congenital stays for life
Strabismus
Mechanism
* Failure of eyes to look in the same direction at
the same time
* Weakness of muscles of one eye
(superior oblique, interior oblique, lateral)
Etiology
◦in childhood: associated with amblyopia
(decreased vision in one eye)
(reversible after 7 years of age)
in adults: Usually caused by disease:
i.e. diabetes, high blood pressure, brain trauma
Symptoms and signs
◦ Types:
1. Esotropia (convergent-cross eye of
one eye)
2. Exotropia (divergent- one eye turns
outward)
3. Diplopia (adults strabismus)
4. Congenital (no strabismus exists)
Diagnosis
◦* complete ophthalmic examination
* Diagnose underlying disease
Treatment
◦* Treat early
* Corrective glasses
* orthoptic training
* surgery to restore eye muscle balance
* treat underlying disorder
Nursing Care Goals
Environmental management –
orientation to the environment 
anxiety & discomfort; facilitates
independance
Emotional support
Family involvement
DISORDERS OF THE EYE
Eyelid Abnormalities
- ptosis : upper lid hangs down
- Ectropian: lower lid hangs
down
- Trichiasis: eyelashes turn in
- Chalazion: eyelid lump
PTOSIS
is an abnormally low position
(drooping) of the upper eyelid.
The drooping may be worse at
night, when the individual's
muscles are tired.
ACUTE RED EYE
Babies (0-28days)- conjunctivitis of
the newborn
Children (6/12-6yrs) – vit. A
deficiency
At any age – conjunctivitis/trachoma,
corneal ulcer/foreign body, iritis,
acute glaucoma
CONJUNCTIVA – DISEASES OF
 Conjunctivitis – inflammation
of the conjunctiva.
 Causes – viral, bacterial,chemical
agents, allergens,physical
irritants, radiant energy
Acute Bacterial Conjunctivitis
Mucopurulant conjunctivitis
Caused by:
Staph epidermidis and Staph
aureus –usually.
Strep pneumonae, H influensae
and Morexella lucanatae
occasionally
Symptoms:
Acute onset of redness, grittiness, burning
and discharge.
*Photophobia may be present (corneal
involvement)
*Stickiness of the eyelids
*Usually bilateral disease
*
Signs:
*Conjunctival
hyperaema
*Mild papillary reaction
*Mucopurulant discharge
*Lid crusting
*No lymphadenopathy.
*Normal VA
TRACHOMA
Chronic relapsing
conjunctivitis
Cause: chlamydia trachomatis
Environmental factors: poor
hygiene, personal & social
TRANSMISSION IS FAVOURED BY:
Crowded living quarters
Shortage of water
Dirty housing
Poor hygiene – animal and human faeces
around the house
All factors which favour the
breeding of FLIES
TRACHOMA
Also spread by sharing unwashed
•Bedding
•Clothing
•Towels
•Face cloths
•handkerchiefs
MOST AT RISK ARE
Children
Young mothers
CLINICAL MANIFESTATIONS
Follicles on underlid
Inflammation
Scarring
Trichiasis
Corneal opacity
PREVENTION OF ACUTE TRACHOMA
Encourage hand & face
washing with clean water
Clean up environment to
Eradicate flies
Intervention
Surgery for trichiasis.
Antibiotics .
Facial cleanliness to prevent
transmission.
Environmental change to prevent
transmission.
Disorders of the Globe of the
Eye Keratitis
Corneal abrasion or ulcer
Scleritis
Cataract
Glaucoma
Macular degeneration
Diabetic retinopathy
Retinal detachment
Uveitis
DISORDERS OF THE CORNEA
Corneal edema – caused by damage to the
epithelium and endothelium of the
cornea.
Keratitis – inflammation of the cornea.
Divided into 2 types
-Nonulcerative – epithelium affected and
still remains intact
-ulcerative – epithelium, stroma or both
are destroyed
AQUEOUS HUMOR & INTRAOCULAR PRESSURE
Glaucoma – group of conditions that
cause an elevation of the intraocular
pressure.
-closed-angle glaucoma
-Open-angle glaucoma
* Congenital or infantile glaucoma
CLINICAL MANIFESTATIONS
Sudden, excruciating pain around
eyes;
headache;
nausea/vomiting;
halos around lights and
sudden blurred vision
DIAGNOSTIC TEST/TREATMENT
Tonometry, non-contact Puff test
Medications:
◦Miotics (which constrict the pupil allowing
better circulation-blurs vision (Pilocarpine)
◦Beta Blockers (which inhibit aqueous humor
production (Timoptic/Betagan)
◦Surgery – last resort when medication fails
DISEASES OF ACCOMMODATION
Develops when patient cannot
accommodate changes from far to
near vision
Cataracts – opacity of the lens and
interferes with the transmission of
light into the retina
COMMON CAUSE OF CATARACT
AGE – over half are
genetically determined
Other causes – drugs,
diseases, damage
PATHOLOGY OF CATARACT
Precipitation of transparent
protein in the lens – becomes
opaque
Like frying an egg
DISEASES
Eye disease – iritis, glaucoma
General diseases – diabetes,
arthritis, syphilis, leprosy,
Down’s syndrome.
DAMAGE
Contusion injury
Perforation
Acids and alkalis
Sunlight
Smoking/alcohol
DIFFERENT CAUSES
Congenital
•Genetic
•Hereditary
•Rubella
•Other viruses
TYPES OF CATARACT
Immature
Mature
Intumescent
hypermature
CATARACTS
Risk factors: age, trauma, toxic agents,
disease, chronic sunlight exposure and
glaucoma or retinal detachment
No pain or eye redness is associated with agerelated cataracts
Visual acuity is very reduced – without
surgery, visual impairment can progress to
blindness
TREATMENT
the only treatment is surgery
CATARACTS
Surgical approaches to lens removal for
cataracts
Replacement lenses are inserted – some
clients have distant vision restored to 20/20
and may only need glasses for reading or
close work
Major complication: increased Intraocular
Pressure and/or Hemmorhage
Another complication: Infection
DISORDERS OF THE RETINA
Blood Supply and Vascular
Lesions – can give rise to
papilledema
Retinopathies – involve
change in structure
RETINAL DETACHMENT
Involves separation of the sensory
retina from the pigment epithelium
with fluid accumulation between the
two layers.
Macular Degeneration
- loss of central vision, usually in both
eyes.
DIABETIC RETINOPATHY
The cells of the retinal vessels die and fluid
leaks into the eye
Fluid is absorbed; thick yellow-white hard
exudates are formed
Capillaries lose their ability to transport
needed oxygen and nutrients
Microaneurysms form in capillary walls.
Capillaries become fragile – bleed easily and
cause retinal ischemia or macular edema
reducing visual acuity
DIABETIC RETINOPATHY
Treatment: depends on the severity of retinal
damage
Laser therapy can seal microaneurysms and
decrease bleeding
Scattering of laser burns across the retinal
can decrease the retina’s need for oxygen and
control the growth of new blood vessels
A vitrectomy can be performed if frequent
bleeding into the vitreous occurs and fibrin
bands threaten to detach the retina
REFERENCES
Brown, D., & Edwards, H (2012). Lewis’s
Medical-Surgical Nursing: Assessment and
Management of Clinical Problems (3rd
ed.).Sydney. Elservier
Dempsey, Maureen Farrell and J. S
meltzer &
Bare's Textbook of
Medical Surgical
Nursing, 3rd Edition. Lippincott Williams &
Wilkins, 10/2013. VitalBook file