What occurs to cerebral perfusion immediately after a cardiac arrest?

In the event of a cardiac arrest, cerebral perfusion is severely compromised due to the cessation of blood flow resulting from the heart's inability to pump. Initially, the brain experiences cerebral hypoperfusion, meaning there is a reduced blood supply. This is critical because the brain relies on a steady supply of oxygenated blood to function properly.

Cerebral hyperaemia refers to an increased flow of blood to the brain, which does not occur immediately following cardiac arrest. Instead, the immediate aftermath of a cardiac arrest leads to hypoperfusion—oxygen deprivation and nutrient deficiency—as the body struggles to maintain blood flow, due in part to the loss of effective cardiac output.

Understanding cerebral perfusion dynamics in the context of cardiac arrest is essential for effective resuscitation efforts. Early intervention is paramount because the brain is particularly sensitive to ischemia, and prolonged hypoperfusion can lead to irreversible damage.