Chapter 28: Spina Bifida (Children) Flashcards
Neural Tube Defects (NTDs)
a group of birth defects in which malformations of the brain and spinal cord occur and the structures lack protection of soft tissue and bone
-develop when the neural tube fails to close during fetal development
>usually the nerves below the defect are impaired
Spina Bifida
“cloven backbone”
- congenital spinal deformity occurring early during gestation (18 to 28 days)
- etiology can be multifaceted, including environmental and genetic risks
- localized defect of the vertebral arch and no spinal cord or meningeal involvement
- a dimple or a tuft of hair may been seen on infants back
Environmental predisposing factors`
- exposure to prolonged hyperthermia
- poor nutrition
- diabetes mellitus
- consumption of seizure medications during early pregnancy
Meningocele
a protruding sac is located on the cervical, thoracic, or lumbar spine at the level of the defect and a thin layer of muscle and skin usually covers the lesion
- meninges (membranes) protrude through the defect in the spine, but no involvement of neural elements is present
- neurological functioning usually not affected
Myelomeningocele
-most severe form; evident upon delivery
-the meninges protrude through the defect, and the meninges contain spinal cord elements
-appears as a very pronounced skin defect, usually covered by a transparent membrane and may even have neural tissue attached to the inner surface
>the higher the defect located on the spine, the greater the loss of spinal cord function because usually no neurological function is found below the defect
>the bony prominences of the unfused neural arches can be felt at the defects lateral border
>when the child is born, the membrane covering the defect may be intact or may leak cerebrospinal fluid (CSF); if membrane not intact, the risk for infection and neuronal damage is increased; until the defect is surgically closed, CSF may accumulate, which results in further dilation and enlargement of the sac, and further neuronal damage may occur
Signs and Symptoms of spina bifida occulta
- least severe form
- visualization of meningocele or myelomeningocele
- weakness
- paralysis
- sensory loss
Signs and Symptoms of Severe Spina Bifida
- visualization of myelomeningocele
- neurological deficits
- hip and joint deformities
- impaired bowel and bladder function
Diagnosis
after 12 to 14 weeks of pregnancy, prenatal diagnosis can be made if the defect is visible through ultrasound
- during pregnancy, maternal serum testing of alpha-fetoprotein performed to determine presence of a NTD; elevated alpha-protein level may indicate NTD b/c open neural defects leak this substance into surrounding amniotic fluid, and a small portion is absorbed into the mothers blood
- on delivery, the defect is usually visible
- defect is examined to determine the type and severity of the defect, and contents of the sac are assessed for meninges, CSF, and spinal cord
- MRI or CT identifies the neurological structures contained in the sac
Prevention
- controlling environmental factors
- pregnant woman decrease exposure to hyperthermia (e.g. saunas and hot tubs)
- pregnant patient with diabetes mellitus monitored; maintain blood glucose levels within normal range by adhering to an appropriate diet, exercise, and medication therapy
- notify healthcare provider if taking anti-seizure medications as taking these while pregnant can result in spina bifida
- women of childbearing age take folic acid to prevent NTDs (good sources: leafy green vegetables, liver, legumes, orange juice, fortified breakfast cereals, and multivitamins)
Nursing Care
- upon delivery, assesses the defect for the type of contents in the sac and measures the defect
- prevention of injury and infection of the sac; sac assessed for infection: redness, purulent drainage, bleeding, and necrosis; if sac ruptures and leaks CSF, the patient is at risk for developing meningitis
- evaluate orthopedic function of newborn; a low thoracic lesion may cause total flaccid paralysis of the lower body; a small sacral lesion may cause only patchy areas of decreased sensation in the feet
- movement or lack of movement of extremities is assessed and documented
- child may have contractures of the hips, knees, and ankles, and the hips may be dislocated; prevent joint contractures or further joint contractures by performing passive range-of-motion exercises (but not with hips)
- clubfeet is a common orthopedic complication b/c fetus cannot move lower extremities in utero; as the child gets older, locomotion is facilitated with the use of wheelchairs, braces, and walkers
The Bladder and Bowel Function of a Child with Spina Bifida
may be affected
- during the neonatal period, assess the voiding and defection patterns of the newborn
- the newborn who constantly dribbles urine may have a neurogenic bladder and may experience urinary retention and overflow with a risk of UTI infections; a newborn who voids at spaced intervals may be able to achieve some level of urinary continence later in life
- constipation and impaction are common; diet needs to include fiber and fluid; stool softeners and laxatives can be administered
- may not be able to feel the urge to defecate; may result in bowel incontinence
- child may need to wear diapers, and as he/she gets older, psychosocial disturbances (depression, embarrassment, and shame) may be experienced
Preventing Injury of the Sac
after birth, as quickly as possible and using sterile technique, cover the defect with a sterile non-adhesive dressing moistened with sterile saline to maintain moisture and prevent drying
- dressing is changed every 2 to 4 hours and when soiled
- place newborn in a prone position and do not place diaper over the defect to prevent pressure on the sac, rupture, and infection of the sac
Do Not Obtain a Rectal Temperature
because rectal irritation and rectal prolapse may occur
Medical Care
- treatment dependent on the form
- with mildest form, spina bifida occulta, often do not need treatment; goal= reducing neurological deficits and preventing complications
Medical Care for more Pronounced/Severe Spina Bifida
more at risk for neurological complications, including meningitis, b/c possibility of infection of the CSF and meninges and possibility of hydrocephalus b/c of obstruction to CSF absorption
>early signs of infection: irritability, elevated temperature, and lethargy
-IV antibiotics administered to prevent infection pre- and post-operatively
-anti-cholinergics to improve urinary continence and antispasmodics to control bladder spasms
-areas where orthopedic devices apply pressure need to be padded and assessed frequently
