Definitions
Define cerebral blood flow
What is the amount of blood flow necessary for the brain to maintain nutritional status and nitrogenous waste clean up
When the pressure inside the skull has increased. This is a medical emergency!
What is increased intracranial pressure
What is a normal CPP (Cerebral Perfusion Pressure)
What is 60 to 100 mmHg
Blood pressure is 82/64. What is the MAP (mean arterial pressure)
What is 70
64x2 + 82/3
128 + 82 = 210 210/3 = 70
What is mental status changes (restless, confused, problems performing normal movements and responding to questions)
Decorticate posturing
What is bringing upper extremities to the core of the body (middle) - adduction and flexion of arms, leg rotated internally, feet flexed
A catheter inserted in the area of the lateral ventricle to assess ICP and drains CSF during increased pressure readings.
What is a ventriculostomy
The range for normal ICP
What is 5 - 15 mmHg (greater than 20 needs medical attention)
Blood pressure is 141/57. What is the MAP (mean arterial pressure)?
What is 85
57x2 + 141/3
114 + 141 = 255. 255/3 = 85
A late sign of increase intracranial pressure
What is irregular breathing (slow down of respirations and irregular…Cheyne-Stokes…hyperventilation then apnea cyclic)
Decerebrate posturing
What is extending the upper extremities from the body - Upper extremities move away from the body
This is the worse of the two (remember all the E’s in decerebrate and think EXTEND arms)
The three structures that control intracranial regulation
What are blood, cerebral spinal fluid and the brain tissue
PaCO2, and why is it important to keep normal
What is 35 - 45, and when blood oxygen levels drop or carbon dioxide levels increase, vasodilation occurs and this increases intracranial pressure.
Blood pressure is 83/40 and the ICP is 20, what is the CPP?
What is 34
CPP = MAP - ICP
40x2 + 83/3 = 54
54 - 20 = 34
Nerve changes to optic and oculomotor nerve include these four things, name two
What is double vision, swelling of optic nerve (papilledema), pupil changes (decreased, increased, or unequal size), abnormal doll’s eyes
Cushing's triad
What is increased systolic blood pressure (widening pulse pressure: increase in SBP and decrease in DBP), decreased heart rate, and abnormal breathing
Late signs, indicates herniation of the brain stem
There are at least 5 things that can cause intracranial pressure to fluctuate. Name three
What are
person’s body temperature
oxygenation status, especially CO2 and O2 levels
body position
arterial and venous pressure
anything that increase intra-abdominal or thoracic pressure (vomiting, bearing down etc.)
CPP incompatible with life
What is < or equal 30
Blood pressure is 81/40 and the ICP is 28. What is the CPP?
What is 42
MAP 40x2+81/3 = 53.6
53.6 - 28 = 41.6, 42
This CPP is incompatible with life
Reflex change
What is positive Babinski's (toes fan out)
Doll's eye reflex
What is oculocephalic reflex…in an unconscious patient open the eyes and move the head from side to side….if eyes don’t move in the opposite direction but stay fixed in a mid-line position this is a very bad sign….indicates brain stem damage
The Monroe Kellie hypothesis
What is if the volume of one of the three intracranial structures increases, the others must decrease their volume to help alleviate pressure
Proper bed positioning for patient with an increased ICP
What is 30 to 45 degree (helps blood return to heart), proper alignment of head (midline) NO flexion of neck (decreases venous return) or hips (increases intra-abdominal/thoracic pressure)…watching moving around in bed
Your patients eye's open to pain, they are muttering incomprehensible phrases, and they are withdrawing from pain. Evaluate the GCS and tell me what that means
What is GCS of 8, get ready to intubate
Neurological changes
What are headaches, seizures, and loss of consciousness (LOC is a late sign)