What percent of ATP depletion leads to changes in neurologic cortical signs? (p.1)
55% ATP depletion
Neurological cortical signs(5)
speechbehaviormemoryjudgmentpersonality
At what temperature does brain cell death occur due to ATP depletion? (p.3)
106 degrees Fahrenheit
In terms of time frame, when does a seizure become a medical emergency? (p.3)
20-30 minutesrapid ATP depletion
Review changes in blood flow during a seizure (increased or decreased). (p.2)
Seizure activity = rapid ATP depletionIncrease in CBF 250-300% to meet metabolic demands of seizure activity
What is the primary energy source for brain function? (p.1)
Glucose - converted to ATP
What effect does increase in BP have on diameter of cerebral arteries? (p.6)
VasoconstrictionIncrease systemic arterial pressure or ICPPrevents hyperemic flow state
What effect does decreased BP have on the diameter of cerebral arteries? (p.6)
VasodilationProtects brain from subflow state and subsequent infarction
Metabolic factors affecting brain's ability to auto-regulate. (p.7)
Increased PaCO2Decreased PaO2Brain injuryIntracranial bleeding
Pressure changes affecting brain's ability to auto-regulate (p.7)
Cerebral vasodilatory drugsChange in MAPIncreased ICP >35 mmHg longer than 20-30 minutes Change in CPP
Normal CPP range
50 - 150 mmHg
Average CPP
80 - 100 mmHg
CPP < 50
Ischemia
CPP > 150
Hyperemia
CPP < 30
Incompatible with life