BACKGROUND: In the first weeks of life there are important maturational changes in the central nervous system in many species in energy metabolism, synapse number, and concentration of neuronal excitatory receptors. METHODS: Four groups of 10 piglets (aged 1, 2, 4, and 10 weeks) underwent 1 hour of deep hypothermic circulatory arrest at 15 degrees C, with cooling and rewarming on cardiopulmonary bypass. Cerebral blood flow and metabolic rate measurements and electroencephalographic recordings were obtained from 5 animals per group. The remaining animals underwent cerebral magnetic resonance spectroscopy. RESULTS: Preoperative cerebral blood flow and glucose consumption were higher at 4 and 10 weeks than at 1 and 2 weeks. Cerebral adenosine triphosphate content decreased more rapidly during deep hypothermic circulatory arrest at 4 and 10 weeks. Phosphocreatine recovery was greater at 30 minutes of reperfusion at 10 weeks compared with 1 week. Recovery of cerebral phosphocreatine/ adenosine triphosphate ratio and intracellular pH was remarkably uniform at all ages. Latency to recovery of electroencephalographic activity decreased with increasing age (p = 0.04). CONCLUSIONS: Differences in acute recovery of brain energy metabolism and electroencephalogram after cardiopulmonary bypass and 1 hour of deep hypothermic circulatory arrest in piglets between 1 and 10 weeks of age are small. Further studies are required to correlate these acute findings with subsequent neurologic outcome.
BACKGROUND: In the first weeks of life there are important maturational changes in the central nervous system in many species in energy metabolism, synapse number, and concentration of neuronal excitatory receptors. METHODS: Four groups of 10 piglets (aged 1, 2, 4, and 10 weeks) underwent 1 hour of deep hypothermic circulatory arrest at 15 degrees C, with cooling and rewarming on cardiopulmonary bypass. Cerebral blood flow and metabolic rate measurements and electroencephalographic recordings were obtained from 5 animals per group. The remaining animals underwent cerebral magnetic resonance spectroscopy. RESULTS: Preoperative cerebral blood flow and glucose consumption were higher at 4 and 10 weeks than at 1 and 2 weeks. Cerebral adenosine triphosphate content decreased more rapidly during deep hypothermic circulatory arrest at 4 and 10 weeks. Phosphocreatine recovery was greater at 30 minutes of reperfusion at 10 weeks compared with 1 week. Recovery of cerebral phosphocreatine/ adenosine triphosphate ratio and intracellular pH was remarkably uniform at all ages. Latency to recovery of electroencephalographic activity decreased with increasing age (p = 0.04). CONCLUSIONS: Differences in acute recovery of brain energy metabolism and electroencephalogram after cardiopulmonary bypass and 1 hour of deep hypothermic circulatory arrest in piglets between 1 and 10 weeks of age are small. Further studies are required to correlate these acute findings with subsequent neurologic outcome.
Authors: Constantine D Mavroudis; Kobina G Mensah-Brown; Tiffany S Ko; Timothy W Boorady; Shavonne L Massey; Nicholas S Abend; Susan C Nicolson; Ryan W Morgan; Christopher E Mascio; J William Gaynor; Todd J Kilbaugh; Daniel J Licht Journal: Ann Thorac Surg Date: 2018-07-30 Impact factor: 4.330