neuromuscular dysfunction

neuromuscular dysfunction

• cerebral palsy

• spina bifida

• muscular dystrophy

cerebral palsy

disorder of posture and movement from static brain injury perinatally or postnatally that limits activity

• often includes disturbances of sensation, perception, communication, cognition, and behavior

• most common permanent physical disability in children

classification of cerebral palsy

• motor abnormalities

  • type

  • severity

• associated impairments

  • seizures, cognitive, communicative, behavioral

• anatomic and radiologic findings

• causation and timing

etiology of cerebral palsy

• variety of prenatal, perinatal, and postnatal factors contribute

• birth asphyxia

• new studies show that CP is often from existing prenatal brain abnormalities

• some causes of congenital CP are:

  • maternal infections

  • jaundice (kernicterus)

  • Rh incompatibility

  • stroke

• infants with history of preterm birth have higher incidence

  • underdeveloped brains, underdevelopment of vessels increases risk of bleeding

• can be from neural injury in utero, during delivery, or in first 2 years of life while brain is rapidly developing

cerebral palsy pathophysiology

• not caused by problems in muscles or nerves but faulty development or damage to motor areas in brain

  • brains ability to adequately control movement and posture is disrupted

• brain abnormalities

  • narrower gyri; sider sulci

  • small, smooth brain

• anoxia causes neural death

  • causes of anoxia were previously discussed

• in few cases, brain did not initially form properly

clinical classifications of cerebral palsy

• spastic CP

• dyskinetic CP

• ataxic CP

• mixed types

spastic CP

• most common form

• muscles appear stiff and tight

• arises from motor cortex damage

• persistent primitive reflexes

dyskinetic CP

• characterized by involuntary movements

• arises from basal ganglia damage

• often will have chorea (jerking movements that are involuntary and irregular) worm, writhing movements

ataxic CP

• characterized by shaky movements

• affects balance and sense of positioning in space

• arises from cerebellum damage

mixed types

combination of 2+ types

clinical manifestations of CP

• delayed gross motor development

• abnormal motor performance

• alternations of muscle tone

• abnormal posture

• reflex abnormalities

• associated disabilities and problems

diagnosis of cerebral palsy

• thorough neuro exam and prenatal, delivery, and postnatal history

  • persistence of primitive reflexes (typically earliest sign)

  • history of preterm delivery

  • maternal infection associated with CP

  • failure to meet developmental milestones on time

• imaging and testing to confirm brain changes associated with CP and rule out other brain lesions

  • CT, MRI, ultrasound, serum testing, EEG

• diagnosis cannot be confirmed until 2 years of age

motor abnormalities in CP

• delay in all motor accomplishments

• increases as growth advances

• delays are more obvious as growth advances

• gross motor:

  • cannot sit up unassisted by 8 months

  • floppy or limp body posture (infant)

  • stiff or rigid arms or legs

  • uses one side of body or only arms to crawl

  • preferential unilateral hand use that may be apparent at 6 months of age

alterations of muscle tone in CP

• increased or decreased resistance to passive movements

• hypotonic

  • present at birth and may persist to one year, then replaced by hypertonic muscle

• hypertonic

  • opisthotonic posturing (arching of back)

  • feels stiff on handling or dressing

  • difficulty in diapering

  • rigid and unbending at the hip and knee joints when pulled to sitting position (early sign)

abnormal postures in CP

• maintains hips higher than trunk in prone position with legs and arms flexed or drawn under body

• scissoring and extension of legs with feet plantar flexed in supine position

• persistent infantile resting and sleeping position

• arms abducted at shoulders

• elbows flexed

• hands fisted

reflex abnormalities in CP

• persistence of primitive infantile reflexes past 6 months

• moro

• tonic neck

• plantar

• palmar grasp

associated disabilities with CP

• altered learning and reasoning

• seizures

• contractures

• impaired behavior and interpersonal relationships

• sensory impairment (hearing and vision)

• failure to smile by 2 months

• feeding difficulties (gagging, choking, tongue thrust after 6 months)

• extreme irritability or crying

• incontinence

• ADHD

problems associated with nonambulatory

• constipation

• orthopedic skin problems

• skin breakdown

• respiratory infections (pneumonia and others)

• feeding difficulties

  • manifests as FTT

  • poor suck

  • tongue thrust

• affects chewing, swallowing, and talking

respiratory problems of CP

• aspiration pneumonia

• chronic respiratory infections

vision and hearing problems with CP

• nystagmus

• amblyopia (lazy eye)

• impaired hearing

oral problems of CP

• cavities

• gingivitis

• malocclusion

scissoring

abnormal walking pattern where legs cross like scissors caused by tight hip adductor muscles

• strongly associated with CP

therapeutic management of cerebral palsy

• physical, occupational and/or speech therapy

  • ROM to prevent contractures; involve family and play

• assistive devices for mobility and ADLs; computers

  • check skin frequently with braces or other assistive devices, reposition often

• surgery to release tendons and improve function

home care for CP

• coping with chronic condition

  • support parents and siblings; offer resources

• education regarding inclusion in school

• use of assistive devices and axercise

• proper medication administration

• prevent skin breakdown and respiratory infections

• nutrition (need for increased calories and rest for dyskinetic CP)

• play and recreation (offer toys to affected side; put toys at distance to encourage locomotion)

• safety needs (prevent accidents, side rails on bed, no scatter rugs)

medication management of CP

• mostly manage associated symptoms

• antiepileptics

• stimulants (ADHD)

• botox

  • paralyzes overactive muscles

• skeletal muscle relaxants

  • dantrolene, baclofen, methocarbamal

• anxiolytics

• bowel regimen

nursing care for cerebral palsy

• assessment and early identification is key

• reinforce therapeutic plan and assist in normalization

  • positive reinforcement to parents

  • offer suggestions and brainstorm with parents

• help improve all muscle tone and control

• address health maintenance needs

  • frequent rest periods needed for child because they expend lots of energy in their efforts to accomplish ADLs

  • meet nutritional needs (G tube or supplemental feedings)

  • routine skin assessment

  • assist and advice regarding medication administration

  • dont forget immunizations

  • safety precautions (wearing helmets when needed, home adaption, modified car seats, etc)

• support family

  • support and help family cope with emotional aspects of chronic disorder

  • family support groups

  • appropriate home resources

    • lifts for larger children

    • assistive devices

    • PT/OT/SLP therapy often

    • respite care may be very beneficial to parents

muscular dystrophy

group of inherited disorders that all result in chronic muscle weakness

types of muscular dystrophy

• duchenne muscular dystrophy (DMD)

  • most common and severe

• beckers muscular dystrophy

  • less severe and common

• limb-girdle and facioscapulohumeral

  • uncommon

duchenne muscular dystrophy (DMD) etiology

x-linked disorder; mom passes defective gene to male offspring or new mutation (mom is not carrier)

DMD pathophysiology

• mutation in gene that encodes dystrophin

• dystrophin is a protein product in muscles

• absence of dystrophin leads to muscle degeneration

early clinical manifestations of DMD

• muscle disease leading to multisystem involvement

• mant children reach appropriate developmental motor milestones early in life but may have subtle delats or hypotonia

• onset usually between 3 and 5 years of age

  • difficulty running, riding bike, climbing stairs 1st symptoms noted

• waddling gait

• lordosis

• positive gowers sign

progressive clinical manifestations of DMD

• pseudohypertrophy from fatty infiltration; muscles are not larger themselves

• muscular atrophy

• ability to ambulate generally lost by 10-12 years

• facial and respiratory muscles atrophy

• cardiac or respiratory failure (most common cause of death)

• mild to moderate cognitive impairment

• median age 27 with mechanical ventilation

complications of DMD

• orthopedic

  • contractures (wrists, hips, knees, ankles, spine)

  • atrophy of disuse (caused by inactivity)

• pulmonary infections

  • decreased ability to cough and clear secretions

• bulbar function and GI

  • mild facial weakness

  • tongue hypertrophy

  • constipation

• obesity

  • inactivity

• cardiac

  • end stages

  • tachycardia, ventricular hypertrophy and dysfunction

DMD diagnosis

• clinical manifestations present, then diagnostic evaluation

• serum enzymes

  • elevated CPK (serum creatinine phosphokinase)

  • elevated SGOT (serum glutamic oxaloacetic transaminase)

• muscle biopsy

  • shows degeneration of muscle fibers

• electromyogram (EMG)

  • shows decreased amplitude and duration of motor potentials

therapeutic goals for DMD

• no curative treatment

• primary goal - to maintain function in the unaffected muscles as long as possible

  • ROM

  • bracing

  • performing ADLs

  • surgery (release contractures)

• genetic counseling

nursing care for DMD

• treat complications

  • contractures and atrophy (PT/OT, orthotics)

• nutrition

  • SLP therapy

• respiratory failure

  • cough assist devices

  • mechanical ventilation/tracheostomy

  • vaccines to prevent lung infections

• cardiac failure

  • diuretics, digoxin

newer/experimental treatments to slow progression

• corticosteroids

• CT GaINAc (blocks muscle wasting)

• glutamine and creatinine monohydrate (preserve muscle strength)

palliative care for DMD

• family and patient coping with disease

• design a program to increase independence

• reduction of preventable disabilities

• modifying home environment

spina bifida

• malformation of spine in which the posterior portion of the lamina of vertebrae fails to close

• failure of neural plate to develop into a tubular structure

etiology of spina bifida

• unknown

• inadequate consumption of B vitamin folic acid before conception and during first trimester

• familial tendency

• more common in caucasian

• more common in girls than boys

pathophysiology of spina bifida

• neural tube fails to close during 4th week of gestation

  • neural grove deepens to form neural tube

  • neural tube continues to grow until the end of 4th week

  • at the end of 4th week, both ends of neural tube close

diagnosis of spina bifida

• most diagnosed post-natally, but some defects visible (open with sac only) or prenatal US

  • prenatal detection (16-18 weeks)

• diagnosis based on imaging of meningeal sac (US, CT, MRI)

• neurological eval ongoing because some clinical manifestations will not be present until child is developmentally delayed

types of spina bifida

• spina bifida occulta

• spina bifida cystica (visible external saclike protrusion)

spina bifida occulta

• defect only in vertebrae, spinal cord and meninges normal

  • defect not visible externally

  • generally have no neurological involvement

  • may see skin depression, simple, or tuft of hair in lumbosacral area on newborn assessment

spina bifida cystics (visible external saclike protrusion)

• meningocele

• myelomeningocele

meningocele

• an external sac encases meninges and spinal fluid

• not associated with neurological deficit

myelomeningocele

• external sac encasing meninges, spinal fluid, and nerves

• location and size of lesion determines degree of neurological deficit

clinical manifestations of myelomeningocele

• develops during first 28 days of pregnancy when neural tube fails to close and fuse at some point along its length

• saclike protrusion evident at birth

• most children with spina bifida develop hydrocephalus

  • enlarged head, sunset eyes, bulging fontanelles

  • can be secondary to type 2 chiari malformation (downward herniation of brain into brainstem)

• varying degrees of sensory and neurological dysfunction

• poor muscle tone in bladder

• poor muscle tone in rectum

• flexion or extension contractures

treatment of myelomeningocele

• surgery - early closure withing first 24-72 hours for most favorable outcomes, first 24 hours there is a CSF leak

  • surgical closure within 24 hours also results in improved b;adder capacities

nursing care of myelomeningocele

• prevention of infection is primary goal (meningitis, UTI)

• sac - moist, sterile NS, nonadherent dressing; no diaper

• UT - keep genitalia clean, may need to catheterize

• protection of lesion/sac is primary goal

  • positioning: prone

  • early closure of sac

  • baby in incubator or radiant warmer so temp can be maintained without clothing that covers lesion

• avoid taking rectal temp because of poor anal sphincter tone which could result in rectal prolapse or lack of bowel control

• VS, weight, I&O, assess pain, observe incision, prone

  • feed when awake, parents hold

• orthopedic interventions to improve locomotion and prevent deformities post-op

  • ROM (prevent contractures), position changes (prevent decubiti)

• treatment of urinary incontinence

  • clean intermittent catheterization (can learn to self-cath by age 6)

  • urinary diversion

    • vesicotomy - augmentation enterocystoplasty; mitrofanoff

• treatment of bowel incontinence

  • bowel training, prevention of constipation, laxatives, digital stimulation, and enemas

  • dietary modifications

  • antegrade continence enema procedure

    • appendix or ileum used to make catheterizable channel with attachment of proximal end to colon; distal end of channel exits through small abdominal stoma

    • every 1-2 days an enema solution administered directly into colon then sits on toilet to have bowel movement

• accurate measurement of head circumference and fontanel

• assess s/s of infection

• provide adequate nutrition and hydration

• latex free environment d/t increased incidence of latex allergy

• promote normal development

  • short stature → growth hormone

• emotional support to family

• encourage parents to take part in care

• teach signs of complications

• educate on neurosensory deficits

• encourage developmental stimulation

• modify appliances and activities

• teach skin care, urinary and bowel control

• resources for spina bifida