Anaesthesia for Myelomeningocele Repair; Precautions to be taken (UPDATED)

🔻Associated conditions: Hydrocephalus, Chiari II malformation, neurogenic bladder/ bowel, short trachea (Take care to avoid endobronchial intubation)hydronephrosis, malrotation of the gut, VSD, ASD, Craniofacial anomalies (Screen for these in first 24 hours after birth, before taking for surgery; may need ECHO, Renal US) Latex allergy is increased in this population Check electrolytes, RFT

🔻Goals of the surgery: Preservation of neural tissue, reconstituion of a normal intrathecal environment, complete skin closure to prevent CSF leak and meningitis. Concern: Most MMCs leak CSF from time of birth--> risk of ventriculitis--> hence closure is recommended within 48-72 hours after birth

🔻Points to ponder:

🔹Take care in prone position to avoid undue pressure over body parts..facial oedema can occur postoperatively

🔹Warmer should be arranged to avoid hypothermia; control the O.R. temperature

🔹Before induction, protect the back defect with sterile donut or rolls

🔹In case of large defects local or myocutaneous flaps may be required to close the defect adequately 

🔹Progressive hydrocephalus establishes after closure of MMC

🔹The efficacy of intrauterine meningomyelocoel repair is being explored 

🔹Anticipate lower brainstem dysfunction 

🔹Need for blood replacement is rare in straight forward cases (EBL ~25 mL)

🔹Usual duration: 1.5-3 hours

🔹If complex repair with fascial release and tight abdomen: better to ventilate for first 24 hours; otherwise on-table extubation can be done

🔹Postoperatively, child is usually nursed on stomach or side; head circumference and head USG are used to monitor for progressive HCP, which may require VP shunt

🔹Post operative complications: wound infection, CSF leak, renal failure, respiratory compromise from tight abdomen

🔹Respiratory complications : hypoventilation, sleep apnoea, bronchospasm, laryngospasm, prolonged breath holding as a result of structural derangement of  medullary respiratory control

🔹Cardiovascular complications: bradycardia, hypotension and tachycardia. Brainstem compression and coning causes most of the  cardiac complications including cardiac arrest when Chiari malformation is  associated with MMC.

🔹Delayed recovery has to be anticipated...so arrange for postop ventilation ( Respiratory centre dysfunction, due to brainstem compression, if there, will again, increase the chance of requirement for post op ventilation) 

🔹Check for swallowing, gag reflex before extubation. Extubation should be performed only when the child is awake and breathing well.

🔹Pain score 3-5