[Verse 1]
Fifty milliliters per hundred grams per minute —
cerebral blood flow keeps the cortex in it
Pressure drops below sixty, autoregulation bends,
a myogenic, metabolic vessel that defends
Carbon dioxide — the master vasodilator,
hypercapnia floods the flow like a tidal renovator
Hyperventilate, you constrict, PaCO2 descends,
but ischemia lurks when the vasoconstriction never ends
Oxygen plays a subtler game — below fifty torr
the vessels finally dilate, screaming out for more
Cerebral metabolic rate drives the coupling tight —
when neurons fire, blood follows, synaptic appetite
[Chorus]
Авторегуляция — hold the pressure steady
Monroe-Kellie — drei Komponenten, always ready
Blood and brain and CSF inside the vault,
one volume rises, something else must halt
Авторегуляция — sixty up to one-sixty
the plateau keeps the perfusion nifty
Монро-Келли — the doctrine never lies —
fixed box, no mercy, pressure always rise
[Verse 2]
The Monro-Kellie doctrine: skull's a rigid dome,
blood, brain, and cerebrospinal fluid share this home
Compensatory compliance — first the CSF retreats,
then venous blood evacuates — but elastance defeats
When all buffering's exhausted, each milliliter more
sends ICP exponential, crashing through the floor
Anesthetic agents split their loyalties here —
volatiles uncouple flow from metabolism, hear —
They vasodilate cerebral vessels, raise ICP,
propofol reduces CMRO2, keeps intracranial free
Ketamine — contested, likely safe with sedation —
yet historically maligned, a tarnished reputation
[Chorus]
Авторегуляция — hold the pressure steady
Monroe-Kellie — drei Komponenten, always ready
Blood and brain and CSF inside the vault,
one volume rises, something else must halt
Авторегуляция — sixty up to one-sixty
the plateau keeps the perfusion nifty
Монро-Келли — the doctrine never lies —
fixed box, no mercy, pressure always rise
[Verse 3]
The choroid plexus weaves its ultrafiltrate slow,
five hundred mils of CSF per day in flow
The blood-brain barrier — tight junctions, astrocyte feet,
lipophilic molecules get a first-class seat
Charged and large? Rejected at the gate —
selective permeability determines drug fate
Anterior spinal artery — a single threadbare seam,
feeds the cord from aortic branches, fragile as a dream
The artery of Adamkiewicz, T8 through L1 zone —
clip it in aortic surgery, the cord is left alone
Anterior cord syndrome — motor, pain, and heat are lost —
posterior columns spared; proprioception bears no cost