DEFICITS OF THE CENTRAL NERVOUS SYSTEM

Neurological Assessment of the Child

Cognitive FunctionBehaviorFacial expressionsGesturesCommunication skills activity levelLevel of consciousness Intellectual ability (based on developmental level of child)

Ability to write or draw Ability to read

Assess Vital signsT/P/RR/BP

Examination of HeadFontanels : bulging, flat, sunkenHead circumference (up to to age 2)Shape of head

Pupillary reactionSizeReaction to lightEquaility of response

Neurological assessment

Level of consciousnessAlertness: response to name and commandIrritabilityLethargy and drowsinessOrientation to self, others, environment

AffectmoodLabiality

Seizure activitytypelength

Sensory functionReaction to painReaction to temperature

Variations in pupil size

Anatomy & Physiology The brain and spinal cord are formed early in gestation from the neural tube. Any insult

or critical event (teratogen, infection, substance abuse, trauma) during this period can result in a CNS malformation. Such defects account for approximately one third of all apparent congenital malformations in live infants and 90% of these defects are neural tube defects.

CNS defects are responsible for 40% of infant deaths during the first year of life. At birth the nervous system is complete but immature. The infant is born with all of the nerve cells that will exist throughout life. The number of glial cells and dendrites, which enable receipt of nerve impulses, continues to increases until approximately 4 years of age.

Mylenation, which increases the speed and accuracy of nerve impulses, is also incomplete at birth. This process continues throughout childhood, proceeding in a cephalocaudal direction. Mylenation accounts for the progressive acquisition of fine and gross motor skills and coordination during early childhood.

Flow of CSF

Anatomic differences between children and adults

Kids are top heavy, head is large in proportion to body, neck muscles not well developed

Prone to head injuries with falls. Neck may not be able to support large head Thin cranial bones that are not well developed, unfused sutures Prone to fractures Highly vascular brain, subarachnoid space is small. Dura firmly attached but

can strip away from pericranium Brain prone to hemorrhage, there is less cerebrospinal fluid to cushion the brain Excessive spinal mobility, muscles, joints capsules and ligaments of cervical

spine immature Greater risk for high cervical spine injury at C1-C2 level Greater risk for compression fractures of vertebrae with falls.

Malformations of the CNS – Neural Tube Defects

Spinal Bifida

The most common defect of the CNS; it involves a midline defect with failure of the bony spine to close.

Two forms: Spinal bifida Occulta and Spinal bifida cystica.

(Wong p 1254 for diagram)

Spinal Bifida Occulta

Occulta – a defect that is not externally visible, may sometimes have a skin depression or dimple at the lumbar sacral area (between L5 and S1) of the spine with a tuft of hair.

Child may have neurologic impairment if the spinal cord is distorted by fibrous bands and adhesions resulting in tethering of the cord to a fixed bony structure.

Some s/s include: bowel and bladder disturbancesdisturbances, gait problems, foot weakness or deformity.

Usually not found until child is having neuromuscular disturbances , beginning to walk or is having difficulty with bowel & bladder control.

Spinal Bifida : Cystica

A visible defect with external sac-like protrusion. Occurs in 2 major forms:

MyelomeningoceleA sac (located outside the spinal column) that contains meninges, spinal fluid,

spinal nerves and parts of the spinal cord. It is associated with varying, often serious, degrees of neuro deficits. The term Spina Bifida generally refers to this type. A sac contains meninges and spinal fluid but not the cord; it is not associated with neuro deficits.

Visible at birth and via ultrasound during pregnancy

MeningoceleA sac (outside spinal column) that contains the menigies and spinal fluid but not

the cord: it is not associated with neurological deficits

Meningomyelocele

ETIOLOGY:

Occurs during first month of conception when neural tube (which will eventually become the spinal cord and canal) fails to close normally. It may be located anywhere along the spinal column, however, majority are found in lumbar or lumbosacral area.

Incidence of spinal bifida increases with previous delivery of an infant with the defect or with anencephaly (congenital absence of both cerebral hemispheres). Decreased incidence with intake of folic acid before conception and during 1st trimester.

PATHOLOGY:

Loss of sensation (sensory), paralysis (motor), loss of bladder and bowel function. These vary in severity. The bladder dysfunction causes constant dribbling or overflow urination with repeated UTIs, reflux, renal insufficiency. Child will need to be straight cathed to empty bladder, parents are taught & when child is about 7 they will be taught how to cath themselves.

Poor anal sphincter tone, lack of bowel control and rectal prolapse. If defect is below 3rd lumbar vertebrae, there is no motor impairment but may be saddle anesthesia, paralysis of anal and bladder sphincters. Child will need bowel training

Sometimes deformities of lower extremities hip dislocation, scoliosis, and result from lack of innervation in utero.

Thoracic lesions have poorest neurologic outcome and vertebral instability

Prenatal diagnosis Pre-natal screening by ultrasound elevated alpha-

fetoprotein between 16-18 weeks. Elective pre-labor C-section may decrease motor

dysfunction.

Prevention 0.4mg Folic acid qd, started 1 month before conception

has shown to reduce the incidence of spinal bifida by50-70%.l

Treatment

Surgical repair within 12- 24 hours prevents infection and trauma to the affected area.

Children with Meningomyelocele frequently have hydrocephalus due to impairment of CSF.

Immediate Care of Myelomeningocele:

Baby is placed in incubator with a warmer without clothes with a normal saline dressing over sac. Baby must be kept prone.

Change dressing q 2-3 hours, keep moist. If sac ruptures during delivery or transport or leakage occurs, check frequently

for signs of infection – temperature (axillary ONLY), irritability, nuchal rigidity (from meningeal irritation). For signs of increasing intracranial pressure.

Infant’s head is turned to one side for feeding or may be held on nurses’ shoulder and someone else feeds baby from behind.

No diapers keep sac clean of urine and stool. Stroke and caress infant, may be placed on pillow on parents’ lap.

Nursing Care:

at birth, assess for associated anomalies: hydrocephalus, paralysis, GU abnormalities, orthopedic anomalies, hypoxia, hemorrhage from lesion site, cardiac anomalies (all mid-line defects)

If there is hope for lower extremity functioning, correction of hip displacement, scoliosis, clubfoot etc will be done. If a lesion is high and child will be confined to a wheelchair, no surgery is performed for orthopedic defects. Children with sacral lesions will be able to walk and will need braces for support and stability.

Bladder infections are monitored with urine C&S. Children usually have in coordination of detrussor muscle (bladder contraction) with sphincter. In infants who have physiologic incontinence, monitoring of the renal and urinary tract for hydronephrosis. In older children, continence may be achieved with urinary anti-spasmodic drugs, Ditropan, affects smooth muscle of GU tract without affecting vascular smooth muscle. Also, intermittent clean catheterization is taught to parents and child.

Some degree of bowel control is achieved with diet (fiber supplements), laxatives, suppositories and or enemas to produce regular evacuation.

Latex allergies in children with spinal bifida

These children have a high % of latex allergy from repeated exposure (urinary catheterizations, surgical procedures) up to 60% develop a latex allergy.

An important nursing intervention in the care of a child with spinal bifida is to reduce the number of latex exposures from the moment of birth.

Post-op Care

generally, prone position, may allow side-lying which allows for position change, decreases risk of pressure sores, and facilitates feeding vital signs, assess for pain, morphine for analgesia

I&O, change and keep clean of urine/stool Weight gain should be same as any other baby, 1 oz/day Assess for neuro status, anal reflex, measure head circumference for increasing

intracranial pressure daily, assess LOC Assess for signs of infection at incision site, UTIs, respiratory, meningeal Assess for urine retention from swelling around operative site. May be

receiving antibiotics and urinary antiseptics. Teach family home care including passive ROM on extremities, stretching to

prevent contractures and maintain flexibility, alignment Teach family to be alert for thermal injury (hot and cold) with infant’s

decreased sensitivity to pressure and temperature. Teach signs of UTI, (can lead to urosepsis and death)

Follow up care

Long range – child will require physical therapy, further surgery. Will need assistive devices, braces, and wheelchair, continence help.

Early intervention services for OT/PT Refer family to spinal bifida association for services and support from other

parents. Children with spinal bifida usually have a normal IQ

Hydrocephaly/Hydrocephalus

ETIOLOGY: Macrocephaly (large cranium) resulting in obstruction in the flow of

CSF through the ventricular system or impaired absorption in the subarachnoid space or increased production of CSF.

CSF is continuously formed by the choroid plexus (tangled masses of tiny blood vessels) of the lateral, 3rd and 4th ventricles in the brain.

Causes of Hydrocephalus

1. Obstruction of flow of CSF

2. Interference with the absorption of CSF

3. Over production of CSF

When the movement or flow of CSF is disturbed, Intercranial pressure increase, the ventricular system enlarges and causes hydrocephalus .

The most common cause of hydrocephalus is Myelomeningocele, intrauterine infections, intraventricular cysts and tumors, intraventricualr hemorrhage, meningitis, and trauma.

Hydrocephalus

Communicating: with impairment of absorption within the subarachnoid spaces

Non-communicating: with obstruction of flow in the ventricular system.

Most non-communicating hydrocephaly is caused by a developmental malformation such as Arnold-Chiari, or Mylelomeningocele. The rest of cases are due to intrauterine infections, Perinatal hemorrhage (most common in pre-term infants) and from trauma in older children.

Arnold-Chiari malformation is seen almost exclusively with Mylelomeningocele, herniation of brainstem, 4th ventricle, and cerebellum through an enlarged foramen magnum. Results in obstruction to flow of CSF and hydrocephalus.

Nursing Assessment of the child with hydrocephalus

S&S are caused by ventricular distention and increasing ICP. In infants with open suture lines, head enlargement is a

prominent sign (head circ greater than 95th percentile) , bulging tense fontanels. Distension of superficial scalp veins (esp. in infant when they cry)

Vital sign changes (increased BP & temperature, decreased RR, HR)

Irritability and lethargy Poor feeding, Vomiting in the infant Seizure activity In infants, “sunset sign”, in which sclera is visible above the

pupil and iris with impairment of upward gaze. Acute manifestations from acute complete obstruction to CSF

flow include HA, vomiting, cranial nerve dysfunctions, herniation of brain and coma follow rapidly.

Changes in LOC, opisthotonos (a prolonged, severe spasm of the muscles causing back to arch acutely, the head to bend back on the neck, heels to bend back on legs and the arms and hands to flex rigidly at the joints), lower extremity spasticity, unequal pupil reaction to light.

In the older child: Frontal headache Ataxia Changes in mental status: behavior changes Lower extremity spasticity Visual changes (diplopic, sunset eyes, papilledema)

VP Shunt

If hydrocephaly develops with permanent impairment to flow or absorption, surgical treatment with placement of a ventriculoperitoneal shunt.

This consists of a ventricular catheter, a flush pump with one-way valve and a distal catheter, which are all radiopaque. Catheter is threaded subcutaneously from ventricles through chest and into peritoneal cavity, where excess tubing is coiled to unwind as child grows. Valve, usually placed behind ear, in front of mastoid bone, opens at a predetermined IC pressure. Fluid is filtered by peritoneal membrane and excreted by kidneys.

VP Shunt

Treatment and Nursing Care of child with Hydrocephalus and a VP Shunt

Support head to prevent strain on neck, feed slowly, feeding before and after handling leads to vomiting, measure head circumference, note changes in LOC

Infection or sudden occlusion may be complications. May result in increasing intracranial pressure, endocarditis, septicemia, brain abscess, and meningitis. CNS infection is also a predictor of intellectual outcome.

Post operative care VP Shunt

keep child flat (lowers risk of rapid decompression of fluid and subdural hematoma) for 2-3 days.

Increased ICP from obstruction of shunt pupil dilation from pressure on oculomotor nerve vital signs, especially BP (rising BP = rising ICP) decreased LOC

poor feeding vomiting seizure activity for abdominal distention from peritonitis or ileus from tube irritation s/s of infection Leakage of fluid at incision site, test any fluid for glucose and if +, CSF. Fluid may

also leak from ears or nose.

Patient/parent teaching

Teach parents signs of infection ,shunt malfunction and Increased ICP. Rarely, the shunt may dislodge in active play or normal growth. Child will live a normal life, only restricted from contact sports.

Intracranial Infections

MeningitisETIOLOGY: An acute inflammation of the meninges.May be bacterial or viral also called aseptic meningitis), an acute inflammation of

meninges and CSF. Bacterial meningitis has a higher incidence between 2 months and 5 years. Organism is usually strep pneumoniae, meningococcus or haemophilus influenza type B (decreased with Hib vaccine).In the newborn the most common organisms are e coli, GABHS, listera.

Meningitis usually follows a URI, It usually occurs from a distal site (Otitis, sinusitis) with bacteremia or nasopharyngeal droplet infection, In newborns, it may occur as a result of premature rupture of membranes in last week of pregnancy.

Once menigies are infected, the organisms are spread throughout the CNS , including the

Neonatal meningitis has a high morbidity with blindness, deafness and significant neurological deficits

90% of infections are in children under 5 years of age More males than females

Clinical Manifestations of Meningitis (all s/s of increased ICP)

In Infants: Young infants have minimal neuro signs of meningeal irritation Irritability “toxic appearance” bulging fontanels nuchal rigidity + Kernig (loss of ability to straighten leg when it is fully flexed at the knee and hip, pain in lower back and

resistance to straightening = + sign) Brudzinski sign (involuntary flexion of the arm, hip and knee when the neck is passively flexed) Seizures high-pitched cry.

In older children HA nausea, vomiting, irritability Anorexia Photophobia Confusion back pain nuchal rigidity seizures

Meningococcal meningitis

Bacterial caused by neisseria mengococcus. Rapid onsets of flu like symptoms, which produces petichae with a purpuric rash and ecchymosis. Very contagious in close quarters (dorms, the military)

If not caught in the first 3-5 hours fulminate disease can occur and it is causes a cascading sequence of events that lead to multi-system organ failure, shock, DIC and death within hours.

If not caught in the first 3-5 hours fulminate disease can occur and it is causes a cascading sequence of events that lead to multi-system organ failure, shock, DIC and death within hours.

There is now a vaccination against neisseria meningococcus but it is only effective with 7 strains, it is advised (and some schools require it) for college students living in dorms and the military.

Treatment and Nursing care (all types of meningitis)

Rapid diagnosis and treatment is the most important intervention to prevent neurological damage.

Respiratory Isolation for at least 24 hours after initiation of treatment IV antibiotics, usually Rocephin for 7-10 days, penetrates CSF and BBB (until

culture and sensitivity comes back) Dexamethasone (Decadron) decreases cerebral edema and incidence of deafness

(from h. influenza) Strict I & O to prevent fluid overload which will increase cerebral edema. Keep room quiet and decrease stimuli in the environment since most children are

sensitive to noise, bright light etc. Elevate HOB slightly with no pillow (pushes head forward), side lying may be

more comfortable. Tylenol with codeine for pain Diet for age if awake and alert Continual assessment of LOC, vital signs, neuro signs and increasing ICP, measure

head circumference on infant

Types of Meningitis

Viral:Viral meningitis is treated symptomatically, LP to rule out bacterial agent;

common illness from other viral illnesses including MMR and live virus vaccines.

Bacterial: Requires 7-10 days of IV antibiotics Immunocompromised children with low T-cell counts from HIV, AIDS are

most susceptible to cryptococcal meningitis, a fungal variety.

Meningitis is usually a benign self-limiting disease (except with some cases of neisseria meningococcal) that resolves with observation of LOC, monitoring of fluid status.

When meningitis is suspected it is assumed it is BACTERIALBACTERIAL andand isolation and antibiotics are begun immediately.