What is the management approach for a patient with an unrepaired myelomeningocele?

Management of Unrepaired Myelomeningocele

An unrepaired myelomeningocele requires urgent surgical closure to prevent central nervous system infection, with antibiotics initiated immediately if closure will be delayed beyond 48 hours. 1

Immediate Priorities

Infection Prevention

• Start prophylactic antibiotics immediately if surgical repair cannot be performed within 48 hours to reduce the risk of meningitis and ventriculitis 1
• The mortality rate for newborns with myelomeningocele is approximately 10%, with infection being a major contributor to morbidity and mortality 2
• While evidence is insufficient to confirm that closure within 48 hours definitively decreases infection risk, delaying closure beyond this timeframe necessitates antibiotic coverage 1

Protective Wound Care

• Keep the exposed neural tissue moist with sterile saline-soaked dressings until surgical repair 3
• Position the infant prone or lateral to avoid direct pressure on the myelomeningocele sac 3
• Handle the defect with extreme care to prevent rupture of the sac, which would increase infection risk 3

Surgical Planning

Timing of Repair

• Early surgical repair (within the first few days of life) is the standard approach to minimize infection risk and preserve neurological function 1, 3
• Early repair should be performed unless the infant is critically ill or has other life-threatening conditions requiring stabilization first 3
• Historically, postnatal closure was performed to prevent central nervous system infection, and this remains the standard when prenatal repair was not performed 1

Surgical Technique Considerations

• The repair requires reversing the failed steps of normal neural tube closure through proper reconstruction 3
• For large defects, utilize all available hairy skin around the defect to achieve tension-free closure 4
• Consider vertical release incisions on one or both flanks parallel to the midline for large defects to decrease wound tension and prevent dehiscence 4
• A simplified two-layer approach using any available tissue type for dural coverage followed by primary skin closure demonstrates excellent outcomes with minimal complications 5

Special Circumstances: Delayed Presentation

• If the myelomeningocele sac has epithelialized (in cases presenting after 6 months), surgical closure requires modification of the typical technique 6
• Epithelialized sacs present unique surgical challenges but can still be successfully repaired 6

Concurrent Management of Hydrocephalus

Shunt Placement Strategy

• Perform ventriculoperitoneal shunt placement simultaneously with myelomeningocele repair if hydrocephalus is present to prevent fluid collection and pressure buildup on the wound 4
• Hydrocephalus is the most frequent comorbidity in myelomeningocele patients, requiring constant neurosurgical surveillance after defect repair 2
• Simultaneous shunting neither prolongs surgery time significantly nor increases cost, but facilitates successful wound closure 4

Monitoring for Hydrocephalus Development

• Children with asymptomatic ventriculomegaly can be managed conservatively without immediate surgery, monitoring for progressive macrocephaly and neurological signs 2, 7
• The evidence on ventricular size impact on neurocognitive development is insufficient and conflicting (Class III evidence) 2, 7

Long-Term Surveillance

Neurological Monitoring

• Monitor carefully for development of tethered spinal cord, which causes deterioration in ambulatory function in both prenatal and postnatal repair patients 1
• Spinal cord tethering or dermoid inclusion cysts are associated with neurological deterioration and loss of ambulation over time 1
• Initial ambulatory status depends on the anatomic level of the neural tube defect 1

Multidisciplinary Follow-Up

• Lifelong multidisciplinary management is required, involving neurosurgery, urology, orthopedics, and physical/social therapy 8, 3
• Orthopedic management addresses spinal deformities (particularly scoliosis) and hip, foot, and ankle complications 8
• Urologic management is essential as part of comprehensive care 8

Common Pitfalls to Avoid

• Do not delay antibiotic initiation if surgery cannot be performed within 48 hours – this is a Level III recommendation despite insufficient evidence for the 48-hour closure window itself 1
• Avoid excessive tension on wound edges during closure, as this leads to necrosis and dehiscence 4
• Do not overlook the need for simultaneous hydrocephalus management, as fluid accumulation can compromise the myelomeningocele repair 4
• Avoid assuming that larger ventricular size automatically requires immediate shunting – conservative management with close monitoring is appropriate for asymptomatic ventriculomegaly 2, 7