What is autoregulation in the cerebral circulation?
Autoregulation of Cerebral Blood Flow. Autoregulation of cerebral blood flow is the ability of the brain to maintain relatively constant blood flow despite changes in perfusion pressure [137].
How does autoregulation affect the brain?
While most systems of the body show some degree of autoregulation, the brain is very sensitive to over- and underperfusion. Cerebral autoregulation plays an important role in maintaining an appropriate blood flow to that region. Brain perfusion is essential for life since the brain has a high metabolic demand.
Does autoregulation occur in the brain?
Autoregulation is a process within many biological systems, resulting from an internal adaptive mechanism that works to adjust (or mitigate) that system’s response to stimuli. While most systems of the body show some degree of autoregulation, it is most clearly observed in the kidney, the heart, and the brain.
What are the two types of autoregulation of blood flow?
At least two different mechanisms contribute to renal autoregulation: the fast, myogenic, and the slower, tubuloglomerular feedback (TGF), responses.
What causes impaired autoregulation?
Cerebral autoregulation is often impaired after TBI,23 and with concomitant high ICP, lead to poor outcome. In children with impaired autoregulation, lower blood pressure may result in diminished CPP and CBF. Decrease in MAP causes cerebral vasodilation, increase in cerebral blood volume, and thus an increase in ICP.
How does autoregulation affect ICP?
When autoregulation is intact, a decrease in CPP results in vasodilation (and increased CBV), leading to increased ICP due to impaired brain compliance. With defective cerebral autoregulation, any decrease in CPP, regardless of its baseline value, will produce a decrease in CBF.
Why is autoregulation of blood flow important?
These resistance vessels dilate in response to reduced pressure and blood flow. This autoregulation is particularly important in organs such as the brain and heart in which partial occlusion of large arteries can lead to significant reductions in oxygen delivery, thereby leading to tissue hypoxia and organ dysfunction.