Head trauma Flashcards
What are the majority of TBIs classified as?
Concussion (65%)
How much CSF is in the brain?
150mL
What is mean arterial pressure?
Pressure driving blood into the brain
- Systole + Diastole x 2/3
- Diastole + 1/3 pulse pressure
What is cerebral perfusion pressure?
Pressure to push blood in cerebral circulation to maintain O2
- BP and ICP
** CPP = MAP - ICP
What is normal CPP?
70-80mmhg
Dura mater is?
inside the skull, tough fibrous layer, Epidural space (potential space)
Pia mater is?
closely adhered to the brain
Arachnoid membrane is?
layered on top of blood vessels adhered to pia
What cushions the brain?
CSF
What CN controls pupillary constriction?
III, herniation in the brain causes pupillary dilation
What do decreased levels of CO2 cause in the blood vessels?
Vasoconstriction
How does hyperventilating help with ICP?
Causes less CO2 which leads to vasoconstriction which then can assist with reducing ICP
What are primary brain injuries?
Direct trauma
What are secondary brain injuries?
Ongoing process from primary injury
What is mass effect?
Elevated ICP which can lead to herniation
What are the 2 biggest predictors to poor outcome in head trauma?
- Increased ICP (>20)
* Hypotension (<90 systolic)
Does the brain need sugar?
Yes, without glucose, neurons will become damaged
What should systolic be maintained at ?
Above 90