Perioperative Care of a Child with Transposition of the Great Arteries

Abstract

Because a minority of patients with D-transposition of the great arteries are diagnosed in utero by ultrasound, most present after delivery with cyanosis. In the absence of apparent lung disease, cyanotic neonates suspected of having a cardiac lesion should be immediately transferred to an intensive care unit at a pediatric tertiary care center for monitoring, resuscitation, and to define the cardiac anatomy and physiology. A prostaglandin E-1 infusion is usually initiated to maintain ductal patency and promote intra-cardiac mixing. In the past, balloon atrial septostomy (BAS) was routinely performed to enlarge the atrial septal defect and improve intra-cardiac mixing while the infants awaited surgery. Recent literature has reported an increase risk of stroke in neonates who undergo BAS, although more recent studies refute this. Our current practice is to perform BAS in neonates who have both echocardiographic evidence of a restrictive atrial septum and hypoxia or instability that is unresponsive to other interventions. The occasional patient who does not respond to initial management may have elevated pulmonary vascular resistance and may stabilize with pulmonary vasodilators, such as inhaled nitric oxide. Rarely, a child does not respond to interventional and pharmacologic resuscitation and requires mechanical support pre-operatively with extracorporeal membrane oxygenation (ECMO). In our experience, ECMO has been a successful bridge to corrective surgery with excellent outcomes. After pre-operative stabilization, arterial switch procedure is typically performed in the first week of life with very favorable early results.

Transposition of the great arteries: When echocardiography does not match the clinical picture

“…The decision to perform a BAS in a neonate with TGA/IVS to improve intracardiac mixing is commonly dictated by the following factors: evidence of a restrictive atrial septum on echocardiogram, hypoxemia, signs of inadequate tissue oxygen delivery, hemodynamic instability, presence of left atrial hypertension, and as a measure to discontinue prostaglandin infusion. 25,26 In our patient, although the presence of minimal atrial mixing was noted, the type II APW proved to be an adequate source of mixing of two parallel circulations which allowed for discontinuation of prostaglandin infusion while maintaining hemodynamic stability, adequate tissue oxygen delivery, and minimized the need for an additional invasive procedure. While having an APW assists mixing of two parallel circulations, not recognizing an APW and having a child unnecessarily undergo a balloon atrial septostomy would not have been in the best interest of the patient and could have resultant unnecessary morbidity associated with it (from known potential complications of balloon atrial septostomies 26 ).…”

“…Furthermore, prenatal diagnosis can reduce the impact on neurodevelopmental outcomes for vulnerable TGA patients, a population that has been shown to have improved postnatal brain development and less preoperative brain injury when a prenatal cardiac diagnosis is made. The decision to perform a BAS in a neonate with TGA/IVS to improve intracardiac mixing is commonly dictated by the following factors: evidence of a restrictive atrial septum on echocardiogram, hypoxemia, signs of inadequate tissue oxygen delivery, hemodynamic instability, presence of left atrial hypertension, and as a measure to discontinue prostaglandin infusion . In our patient, although the presence of minimal atrial mixing was noted, the type II APW proved to be an adequate source of mixing of two parallel circulations which allowed for discontinuation of prostaglandin infusion while maintaining hemodynamic stability, adequate tissue oxygen delivery, and minimized the need for an additional invasive procedure.…”