Final answer:
The first nursing intervention for a newborn with a myelomeningocele is to apply a sterile saline dressing to prevent infection and protect the exposed spinal cord until surgery can be performed.
Step-by-step explanation:
The first nursing intervention for a newborn with a myelomeningocele who is transferred to the neonatal intensive care unit (NICU) is D. Apply a sterile saline dressing. This is crucial to prevent infection and additional damage to the exposed spinal cord and nerve tissues. Myelomeningocele is a type of spina bifida involving a sac of fluid that comes through an opening in the baby's back. One of the immediate concerns is the risk of infection to the exposed tissues, and applying a sterile saline dressing helps to maintain a moist environment that can protect the site until surgery can be performed.