MALFORMATIONS OF THE NERVOUS SYSTEM
Cranial Defects:
- Craniosynostosis
• one or more of the sutures close too soon
• ICP increases; interfeeres with normal brain growth à MR
Assessment:
• suture lines of the skull manually palpated
• Radiographs are made to confirm
- Microcephaly
• The brain fails to grow
• May be due to a chromosomal defect or from drugs, toxins or radiation
• MR
- Hydrocephalus
• Imbalance of CSF absorption or production
• caused by malformations, tumors, hemorrhage, infection, trauma
Types:
- Communicating – impaired absorption within arachnoid space
- Non-communicating – obstruction of CSF flow within the ventricular system
Assessment:
• Infant – increased HC
• Macewen’s sign – cracked-pot sound on percussion of bones of head
• Anterior fontanel tense, bulging
• Scalp veins dilated
• Frontal bossing, sunsetting eyes
• Child – behavior changes
• Headache, nausea and vomiting
• Ataxia, nystagmus
Surgical Implementation: Hydrocephalus
Goal: to prevent further CSF accumulation by bypassing the blockage and
draining the fluid from the ventricles to a location where it may be
reabsorbed
- VP Shunt – CSF drains into the peritoneal cavity from the lateral ventricle
- AV shunt – CSF drains into the right atrium
PostOP Care:
- Keep child flat as prescribed – to avoid rapid reduction of intracranial fluid
- Observe increase ICP – if present, elevate HOB 15-30 deg
- Monitor for infection
- Measure HC
- Monitor I and O
- Provide comfort measures; administer medications (diuretics, antibiotics, or anticonvulsants)
- Toddler – headache and anorexia à earliest common signs of shunt malfunction
SPINA BIFIDA
• CNS defect that occurs as a result of neural tube failure to
close during embryonic development
• defect closure usually done during infancy
Types:
- Spina bifida occulta
• Posterior vertebral arches fail to close in the lumbosacral area
• Spinal cord intact; not visible
• Meninges not exposed on the skin surfaces
- Meningocoele
• Protrusion involves meninges and a sac-like cyst
• Lumbosacral area
- Myelomeningocoele
• Protrusion of meninges, CSF, nerve roots, portion of spinal cord
• Sac covered by a thin membrane à may rupture or leak
• Neuro deficit evidence
Assessment:
• Depends on spinal cord involvement
• Visible spinal defect
• Flaccid paralysis of legs
• Altered bladder and bowel function
Implementation:
• Evaluate sac; measure lesion
• neuro check
• monitor for increase ICP
• measure HC; assess fontanelles
• Protect the sac
1. Cover with sterile, moist (normal saline) non-adherent
dressing
2. Change dressing every 2-4 hours
• Place prone position
• head is turned to one side for feeding
• diapering may be C/I until defect repaired
• Aseptic technique
• Watch for early signs of infection
• Administer antibiotics
• Administer anticholinergics – improve urinary continence
• Administer laxatives , antispasmodics
MENINGITIS
• infectious process of the CNS caused by bacteria and viruses
• acquired as a primary or as a result of complications
• diagnosis – CSF analysis (increase pressure, cloudy CSF, high protein, low glucose
• bacterial or viral
Assessment:
• signs and symptoms vary depending of age group
• fever, chills
• vomiting, diarrhea
• poor feeding or anorexia
• altered LOC
• bulging anterior fontanel
• nuchal rigidity
Implementation:
• isolation; maintain for at least 24 hours after antibiotics are initiated
• administer antibiotics as prescribed
• monitor VS and neuro status
• Monitor I and O
• assess nutritional status
• determine close contacts of the child with meningitis
SEIZURE DISORDERS
• Sudden transient alterations in brain function resulting from excessive levels of electrical activity in the brain
Assessment:
• obtain information from parents about the time of onset, precipitating events and behavior before and after the seizure
• seizure precautions:
- Raise side rails
- Pad side rails
- Place waterproof mattress on bed
- Instruct child to swim with companion
- Alert caregivers to the need for special precautions
Emergency Treatment for Seizures:
• Ensure patency of airways
• If the child is standing or sitting, ease the child down to the floor
• place pillow or folded blanket under the child’s head
• loosen restrictive clothing
• clear area of any hazards
• if vomiting occurs, turn child to one side
• do not restrain child; do not place anything in the child’smouth
• Remain with the child until fully recovers
• Prepare to administer medications
CEREBRAL PALSY
• disorder characterized by impaired movement and posture resulting from an abnormality in the extrapyramidal motor system
• spastic type- most common
Assessment:
• extreme irritability and crying
• feeding difficulties
• stiff and rigid arms and legs
• delayed gross development
• abnormal motor performance
• alterations of muscle tone
• abnormal posturing
• persistence of primitive reflexes
Implementattion:
• early recognition
• PT, OT, speech therapy, eduaction and recreation
• assess the child’s developmental level and intelligence
• early intervention
• encourage communication and interaction with the child on a functional level
• provide safe environment
• position upright after meals
• provide safe, appropriate toys for age and developmental level
NEURAL TUBE DISORDERS
· “SPINA BIFIDA”
o Latin for “divided spine”
· “CLEFT SPINE”
· All of the disorder occur because of lack of fusion of the posterior surface of the embryo in the early intrauterine life
· ‘closure disorder’
· INCIDENCE:
o May occur as a polygenic inheritance pattern
o poor nutrition – folic acid deficiency
· TYPES OF DISORDERS
o ANENCEPHALY
§ Absence of the cerebral hemispheres
§ Occurs when the upper end of the neural tube fails to close in early intrauterine life
§ Elevated AFP during pregnancy
§ Incompatible to life
o MICROCEPHALY
§ d/o in which brain growth is so slow that it fails more than three standard deviations below normal on growth charts
§ associated with: rubella, cytomegalovirus, or toxoplasmosis
§ Cognitively challenged
o SPINA BIFIDA OCCULTA
§ Occurs when the posterior laminae of the vertebrae fails to fuse
§ Occurs most commonly at the fifth lumbar or 1st sacral level
§ Characteristic:
· Dimpling at the point of poor fusion
· Abnormal tufts of hair or discolored skin may be present
o MENINGOCOELE
§ Herniation of the meninges covering the spinal cord through unformed vertebrae
§ Presence of orange, protruding mass at the center of the back
§ Occurs in the lumbar region
o MYELOMENINGOCOELE
§ The spinal cord and the meninges protrude through the vertebrae
§ The spinal cord ends at the point resulting to the absence of sensory and motor function at the point of the d/o
§ Flaccidity
§ Lack of sensation of the lower extremities
§ Loss of bowel and bladder control
§ Hydrocephalus accompaniment
o ENCEPHALOCOELE
§ Cranial meningocoele
§ Occurs most often in the occipital area of the skull but may occur as a nasal or nasopharyngeal d/o
· ASSESSMENT
o Check the nature and pattern of voiding and defecation
o “voids continually”
o “defecates continually”
o Pressure on the protruding mass can rupture the sac, leading to a quick decompression of the CSF
§ May lead to herniation of the brain stem into the spinal cord and interference with respiratory and cardiac centers
· NURSING DIAGNOSIS
o Risk for infection
o Impaired physical mobility
o Risk for impaired elimination
· MANAGEMENT
o Parents should be made aware about the defect
o Avoid drying of the sac to prevent infection and CSF drainage
o Prone or side-lying position
o Use a rolled blanket or diaper placed behind the child’s upper back (above the d/o) and a separate one behind their lower back (below the d/o)
o May cover the area with sterile wet dressing
o Avoid rupturing the sac!
o Always check any leakage for evidence of glucose to confirm if the fluid is CSF
ARNOLD-CHIARRI MALFORMATION
· Overgrowth of the neural tube in weeks 16 to 20 weeks of fetal life
· Projection of the cerebellum, medulla oblongata, and 4th ventricle into the cervical canal
o This projection causes the upper cervical spinal cord to jackknife backward, obstructing CSF flow and causing hydrocephalus
· Absent gagging and swallowing reflexes
o Increasing risk for tracheal aspiration
REYE’S SYNDROME
· Acute encephalitis with accompanying fatty infiltration of the liver, heart, lungs, pancreas, and skeletal muscle
· Occurs in children 1 to 8 years of age regardless of gender
· Cause: unknown
· Possible cause: after a viral infection
· FATAL!
· ASSESSMENT
o Lethargy
o Agitation
o Anorexia
o Confusion
o Combativeness
o Mimic the sx of drug intoxication
o Progression of cerebral symptoms
§ From confusion to stupor to deep coma
o Seizures
o Respiratory arrest due to pressure on the brainstem
o Elevated ALT or SGPT and AST – confirmatory
o Definitive diagnosis- fatty infiltration on liver biopsy
· MANAGEMENT
o Directed toward the symptoms
STURGE-WEBER’S SYNDROME
· ENCEPHALOFACIAL ANGIOMATOSIS
· Congenital port-wine birthmark on the skin of the upper part of the face that extends inward to the meninges and choroid plexus
· Defect is unilateral
· Blood flow is sluggish and anoxia may develop
· ASSESSMENT
o Hemiparesis on the side opposite the lesion
§ Due to destruction of motor neurons
o Intractable seizures
o Calcification of the cerebral cortex
· MANAGEMENT
o Surgery
NEUROFIBROMATOSIS
· VON RECKLINGHAUSEN’S DISEASE
· Unexplained development of subcutaneous tumors
· Can occur as mutation or inherited as an autosomal dominant trait carried by the chromosome 17
· With presence of irregular but excessive skin pigmentation
· Characteristic: presence of more than 6 spots larger than 1 cm in diameter
· With hearing loss
· Vision impairment
· FATAL!
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