Effects of Cardiac Arrest on the Brain

Cardiac arrest (CA) is a sudden stop in effective blood circulation due to the failure of the heart to contract effectively or at all. Arrested blood circulation prevents delivery of oxygen and glucose to the body. Lack of oxygen and glucose to the brain causes loss of consciousness, which then results in abnormal or absent breathing. Brain injury is likely to happen if cardiac arrest goes untreated for more than five minutes. During total circulatory arrest, lack of cerebral oxygenation results in loss of ATP production and dysfunction of membrane ATP–dependent Na-K pumps. Subsequent loss of cellular integrity triggers the release of glutamate, which causes excitotoxic injury. Global cerebral ischemia during cardiac arrest results in heterogeneous injury to the brain. Large projection neurons of the cerebral cortex, cerebellar Purkinje cells, and the CA-1 area of the hippocampus are the most vulnerable areas