Neonatal brain protection in cardiac surgery and the role of intraoperative neuromonitoring

Contrast-enhanced ultrasound of the pediatric brain

Brain contrast-enhanced ultrasound (CEUS) is an emerging application that can complement gray-scale US and yield additional insights into cerebral flow dynamics. CEUS uses intravenous injection of ultrasound contrast agents (UCAs) to highlight tissue perfusion and thus more clearly delineate cerebral pathologies including stroke, hypoxic-ischemic injury and focal lesions such as tumors and vascular malformations. It can be applied not only in infants with open fontanelles but also in older children and adults via a transtemporal window or surgically created acoustic window. Advancements in CEUS technology and post-processing methods for quantitative analysis of UCA kinetics further elucidate cerebral microcirculation. In this review article we discuss the CEUS examination protocol for brain imaging in children, current clinical applications and future directions for research and clinical uses of brain CEUS.

Innominate artery cannulation and antegrade cerebral perfusion for aortic arch reconstruction in infants and children

PURPOSE

Innominate artery cannulation has been widely adopted as a means to perform aortic arch reconstruction with continuous cerebral perfusion in the newborn. Although this technique has been subsequently utilized in infants and children, there is currently no data regarding the safety or efficacy in these older children. The purpose of this study was to review our experience with innominate artery cannulation for aortic arch reconstruction in patients beyond the neonatal period.

METHODS

This was a retrospective review of 42 infants and children who underwent aortic arch reconstruction using the technique of innominate artery cannulation with continuous cerebral perfusion. Of these procedures, 29 (69%) were primary arch reconstructions, while 13 (31%) were aortic arch reoperations. The median age at surgery was 8 months, and 22 patients underwent concomitant intracardiac repairs.

RESULTS

There was no operative mortality in this cohort of 42 patients undergoing aortic arch reconstruction. There was also no overt evidence of neurologic injury. Specifically, none of the patients demonstrated a neurologic deficit, clinical seizure, or unexpected delay in regaining a normal state of consciousness. The median duration of antegrade cerebral perfusion was 34 minutes. The median duration of hospital stay was 11 days. No patient required reoperation on the aortic arch with a median of 45-month follow-up.

CONCLUSIONS

Innominate artery cannulation is a safe and effective technique for aortic arch reconstruction in nonneonates. We conclude that antegrade cerebral perfusion is a useful technique for aortic arch reconstruction in this patient population.