Neurodevelopmental outcome related to cerebral risk factors in children after neonatal arterial switch operation

Objectives

Prospective study to evaluate midterm neurodevelopmental status in childhood and to correlate it to pre-/perinatal asphyxia, intraventricular cerebral haemorrhage, seizures and neuronal cell damage after neonatal arterial switch operation for transposition of the great arteries with combined cardiopulmonary bypass (CPB) and deep hypothermic cardiocirculatory arrest.

Methods

Protracted birth (PB), perinatal asphyxia (PA), intraventricular cerebral haemorrhage (IVH) evaluated by pre/peri/postoperative cranial ultrasound, clinical seizures (CS) and high levels of the neuron-specific enolase (NSE) prior to as well as immediately after and 4 and 24 h after CPB in 25 neonates (mean age 7 days) were defined as cerebral risk factors. Correlation analyses (Fisher's Exact Test, Pearson Coefficient) were performed to the results of formalized clinical neurological (CNS) and complete developmental score (CDS) including 7 subtests (Vienna developmental test, standard values defined normal 100 ± 10, mean ± SD) at mean age 3.7 ± 0.5 years.

Results

PB was found in 16%, PA 0%, IVH 48%, residual IVH at discharge 24%, CS prior to surgery 16%, CS > 24 h after CPB 12%. NSE, elevated prior to surgery (11.3 ± 4.5 ng/ml, mean ± SD), increased to peak values 4 h after CPB (17.3 ± 6.0) and individual peak values within 24 h after CPB (19.9-7.0). CNS was normal in 84%, 16% had strabism. CDS was normal in 88% (100 ± 8), motor score 96% (99 ± 6), visual perception 88% (100 ± 9), learning and memory 96% (102 ± 7), cognitive score 100% (101 ± 8), language 100% (99 ± 5), socioemotional score 100% (103 ± 7). Developmental scores did not differ significantly from normal children. None of the considered risk factors had significant influence on any outcome parameter (P > 0.1 in all).

Conclusions

In our study, neurodevelopmental outcome was not found dependent on cerebral risk factors as elevated NSE indicative of neuronal cell damage, intraventricular haemorrhage, seizures or pre-/perinatal asphyxia. Rare incidence of reduced test results might have masked significant correlations.