Preclinical <scp> ¹ H MRS </scp> Study of a Porcine Model Shows Evidence and Mechanisms for Acute Neuronal Injury in Neonatal Cardiopulmonary Bypass ( <scp>CPB</scp> ) Surgery

PURPOSE: H MRS in a neonatal CPB porcine model to assess acute neuronal damage and associated injury mechanisms. METHODS: ). Hypothermic temperatures ranged between 18°C-37°C, and blood glucose (Glc) levels immediately prior to CA ranged from 54 to 700 mg/dL. Acute neuronal injury at ∼1 h post-CA was assessed by decreased N-acetyl aspartate (NAA) and correlated with three potential injury mechanisms: (1) energy failure via pre-CA Glc and phosphocreatine (PCr) loss during CA, (2) reperfusion injury via elevated succinate (Suc) at end of CA, and (3) ammonia toxicity via post-CA glutamine/glutamate (Gln/Glu) levels. RESULTS: or Gln/Glu changes. CONCLUSIONS: during CA.