Background and purpose: Brain injury is common in newborns with congenital heart disease (CHD) requiring neonatal surgery. The purpose of this study is to define the risk factors for preoperative and postoperative brain injuries and their association with functional cardiac anatomic groups.
Methods: Sixty-two neonates with CHD were studied with preoperative MRI, and 53 received postoperative scans. Clinical and therapeutic characteristics were compared in newborns with and without newly acquired brain injuries. A subset of 16 consecutive patients was monitored with intraoperative cerebral near-infrared spectroscopy.
Results: Brain injury was observed in 56% of patients. Preoperative brain injury, seen in 39%, was most commonly stroke and was associated with balloon atrial septostomy (P=0.002). Postoperative brain injury, seen in 35%, was most commonly white matter injury and was particularly common in neonates with single-ventricle physiology and aortic arch obstruction (P=0.001). Risk factors associated with acquired postoperative brain injury included cardiopulmonary bypass (CPB) with regional cerebral perfusion (P=0.01) and lower intraoperative cerebral hemoglobin oxygen saturation during the myocardial ischemic period of CPB (P=0.008). In a multivariable model, new postoperative white matter injury was specifically associated with low mean blood pressure during the first postoperative day (P=0.04).
Conclusions: Specific modifiable risk factors can be identified for preoperative and postoperative white matter injury and stroke associated with neonatal surgery for CHD. The high incidence of postoperative injury observed despite new methodologies of CPB indicates the need for ongoing evaluation to optimize neurological outcome.