ABSTRACT
The increasing use of cardioplegia to protect the heart from ischemia during cardiac surgery led our laboratory to investigate whether cerebroplegia could be useful for the brain. The cerebroplegia animals had an initial infusion of cold oxygenated crystalloid solution through the carotid arteries and additional boluses every 20 minutes during the arrest period. All animals underwent reperfusion at the end of two hours of circulatory arrest. The effect on brain protection of low perfusion flows or intermittent perfusion during systemic hypothermia was examined to determine the minimal hypothermic bypass rate at which cerebral metabolism, as evidenced by nuclear magnetic resonance, could be preserved. An ovine coma score was developed and used to assess the neurologic status of the animals. With either antegrade cerebroplegia or simply icing the head combined with systemic hypothermia, all of the animals had enough neurologic function to be extubated and had higher neurologic scores than did the control or retrograde cerebroplegia animals.
