31P nuclear magnetic resonance study of the effect of hypoxemia on neonatal status epilepticus

Abstract

Prolonged neonatal seizures are often accompanied or exacerbated by hypoxemia. To determine the effects of hypoxemia on neonatal status epilepticus, we determined cerebral blood flow and cerebral metabolic state in groups of neonatal dogs subjected to hypoxia, to seizures during normoxia, or to seizures during hypoxia. The compensatory increase in cerebral blood flow was greatest in animals subjected to seizures during normoxia and somewhat less pronounced in animals made hypoxic. However, blood flow failed to increase in forebrain structures when animals were subjected to the combination of seizures and hypoxia. Accordingly, levels of adenosine triphosphate in forebrain (measured both by in vitro enzymatic analysis and by in vivo phosphorus-31 nuclear magnetic resonance spectroscopy) were depleted to the greatest degree in animals who were seizing while hypoxic. In addition, brain glucose was significantly reduced only in the seizure-hypoxia group. Systemic factors such as hypoxemia may play a critical role in the disruption of cerebral energy balance during neonatal status epilepticus. © 1986 International Pediatric Research Foundation, Inc.