Preclinical 1H MRS Study of a Porcine Model Shows Evidence and Mechanisms for Neuronal Injury in Neonatal Cardiopulmonary Bypass Surgery

Motivation: To investigate metabolic processes contributing to neuronal damage during neonatal cardiopulmonary bypass (CPB) surgery. Goal(s): Use 1H MRS to measure changes in glucose, phosphocreatine, succinate, and ammonia during different phases of CPB surgery and assess their correlations with N-acetyl-aspartate (NAA), a marker of acute brain injury. Approach: Studies were conducted on a porcine model at varying bypass temperatures, using either antegrade cerebral perfusion or complete circulatory arrest (CA), to examine effects on neuronal injury. Results: 1H MRS detected brain damage that correlated with surgical parameters and key metabolites, with greater NAA losses observed during CA and at higher temperatures. Impact: Understanding how different surgical approaches affect patient outcomes will enable clinics to implement safer protocols for neonates with congenital heart disease, who face a greater risk of neurodevelopmental delays from these critical procedures.