Neuroanesthesia Pt. 2 (Exam I) Flashcards
How much CSF do we typically have at any given moment?
150mls
Where does CSF typically “pool”?
Cisterns
Areas where arachnoid membrane and pia mater are further apart.
Don’t need to know specific cisterns.
What is normal CSF pressure for a horizontal patient?
10 mmHg
What type of tissue lines the cerebral ventricles?
What does this tissue do?
Choroid Plexus (produces CSF)
Which cells excrete CSF?
Ependymal (E = Excrete)
What absorbs CSF?
Arachnoid Villi (A = Absorb)
What is the path of CSF?
In which ventricles is the majority of CSF produced?
Lateral Ventricles
CSF Diagram (Flip)
What is idiopathic Intracranial HTN?
CSF Buildup causing ↑ICP with no obvious reason.
Who is idiopathic intracranial HTN common in?
- Obese women of reproductive age.
What is another name for idiopathic Intracranial HTN?
Pseudotumor Cerebri
What is normal ICP?
7 - 15 mmHg
When is ICP considered pathologic?
> 20 mmHg
Whats a normal CPP?
60 - 80 mmHg
What is the critical ischemic threshold for CPP?
30 - 40 mmhg
What would the following do to CBF?
- Hypoxia
- Hypercarbia
- ↑ CMRO₂
↑CBF
Where does aqueductal stenosis occur?
Aqueduct of Sylvius (between 3ʳᵈ & 4th ventricles)
What are the three components of Cushing’s Triad?
- Irregular Respirations
- Bradycardia
- Widened pulse pressure
How long might the effects of hyperventilation on PaCO₂ last?
6 - 12 hours
What dose of Mannitol is typical in neurosurgery?
0.5 - 1 mg/kg
What are the benefits of corticosteroids in neurosurgery?
What are the negatives?
- Pros: Lowers local cerebral swelling (around tumors typically)
- Cons: May ↑BG and ↓ elasticity of blood vessels
What is parenchyma?
Functional Brain Tissue (grey & white matter)
What are potential concerns associated with utilizing hyperventilation to induce brain relaxation?
- Potential ischemia in some areas
- Brain relaxation temporary (6 - 12 hours)