Neonate With d-TGA and Restrictive Atrial Septum Awaiting Transfer
A 3-day-old term neonate with prenatally suspected d-transposition of the great arteries is admitted with cyanosis. Prostaglandin E1 was started at the referring hospital. Current saturation is 72% preductal and 70% postductal, respiratory rate 70, lactate 6.2 mmol/L, and urine output 0.8 mL/kg/h. Echocardiography shows d-TGA with intact ventricular septum, a restrictive patent foramen ovale (2 mm), and a small patent ductus arteriosus. The nearest cardiac surgical center is 90 minutes away by air. The local catheterization laboratory can perform balloon atrial septostomy but has no on-site congenital cardiac surgery.
1. What immediate steps are needed before and during transfer?
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This neonate has inadequate atrial mixing and is becoming acidotic. I would secure the airway and ventilate gently, avoiding hyperoxia, which can close the ductus and worsen mixing. Continue prostaglandin E1 and be prepared for apnea; keep the ductus open. Correct acidosis, glucose, calcium, and temperature, and avoid excessive sedation that could depress cardiac output. Because the local center can perform balloon atrial septostomy, I would perform it before transfer if the team is experienced and the baby is unstable; otherwise, transfer urgently with a neonatal transport team capable of intubation and resuscitation. The surgical center should be alerted. If saturation remains below 65% with worsening lactate despite these measures, immediate septostomy is mandatory before transport.
2. What are the indications, risks, and timing of balloon atrial septostomy and arterial switch operation?
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Balloon atrial septostomy is indicated for restrictive atrial mixing with cyanosis or acidosis, or when the patent foramen ovale is inadequate. It creates a larger atrial communication and improves systemic oxygenation. Risks include atrial perforation, arrhythmia, and systemic embolization; it should be performed with echocardiographic guidance by an experienced operator. After septostomy, the infant is stabilized and the arterial switch operation is usually performed within the first 1–2 weeks of life, before the left ventricle loses its ability to support the systemic circulation. If the left ventricle is already deconditioned, a staged approach may be needed. The decision should be made by the congenital heart team with serial echocardiography.
3. If balloon atrial septostomy cannot be performed locally and saturations fall to 60%, what would you do?
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A saturation of 60% with worsening acidosis indicates that atrial mixing is critically inadequate; waiting for transfer is dangerous. I would activate the nearest congenital interventional team and consider whether the local team can safely perform septostomy with telephonic or telemedicine guidance. If not, I would arrange the fastest possible transport with a neonatal intensive care team, continue prostaglandin, optimize ventilation, and treat acidosis. In extreme cases, emergency surgical septectomy at the receiving center may be required. The key judgment is that a restrictive atrial septum in d-TGA can be lethal even with a patent ductus, so the threshold for urgent septostomy should be low.