Patho 2 Flashcards
What direction is bad in skull fractures
in is bad
what are risks associated with depressed skull fractures
- disruption of tightly adherent dura
- tear of meningeal vessels
- contuse/lacerate underlying brain tissue
- can communicate with facial sinuses (MC maxillary) or middle ear
- infection/meningitis
Thinnest part of the skull is where? what blood vessel is associated?
- near the temple
- middle meningeal artery (epidural)
What are the sx of a basal skull fracture?
- raccoon eyes
- CSF leak out nose or ear
What is best imaging for skull fracture?
CT!!! Don’t bother with plain film
- start w/o, once r/o bleed, then can do contrast if needed
What is common secondary issue with brain injury?
Coup contracoup injury
- coup at site of injury
- contracoup opposite side of injury
Concussion
- occurs after trauma in absence of demonstrable damage to cranium or brain
- transient loss of consciousness
- amnesia (retro- and anterograde)
- minor damage to CNS
- lasting effects are minimal unless injury is repetitive
Dementia pugilistica
“punch drunk”
- fighters in past who had damage due to multiple concussions
Brain contusion
- caused by waht
- level of damage
-
- d/t violent motion or fast stopping - brain hits calvarium (skull)
- shaken baby syndrome and acceleration/deceleration injuries
- produces underlying local damage
- can be transient/minor OR produce enough damage to cause epilepsy
Brain contusion
- common brain locations of damage
- inferior surface of frontal lobes
- anterior tip of temporal lobes
- occipital poles
- may act as foci of seizure activity, esp. temporal lobes
Where is location of middle meningeal artery bleed?
Epidural
What type vasculature is typically bleeding in subdural bleeds?
- Venous – cerebral veins
- Lower pressure, sx over a longer period of time compared to epidural bleed
What type of bleeds will produce blood in a spinal tap?
- Subarachnoid – blood is between arachnoid and pia where CSF is
- Not subdural
Epidural hematoma
- location
- cause
- sx
- tx
- Between skull and dura mater
- Tearing of middle meningeal artery
- Characterized by transiet loss of consciousness with subsequent lucid interval
- 2 hours to repair!
- Surgical drainage prevents rapid expansion, brain herniation, death
Subdural hematoma associated with what cause
blunt trauma w/o overlying skull fx
Subdural hematoma acute vs. chronic
Acute
- Become clinically apparent a few days after trauma
- Fluctuating levels of consciousness
Chronic
- Clinically apparent weeks or months after trauma
- Slowly developing confusion/inattention, eventually coma
Symptoms of ICP
- HA
- vomiting
- drowsy
Describe a subarachnoid hemorrhage
- damage to blood vessels on surface of the brain (in the pia)
- Trauma most common, can also be aneurysm or arteriovenous malformation
- Does result in bloody tap
What causes papilledema
- Increased CSF, commonly subarachnoid hemorrhage
- Epidural and subdural less likely but possible if large enough
What should never be done if suspect increased ICP?
Spinal tap, risk for herniation in brain (very bad)
What areas of brain are most sensitive to hypoxia?
Medial temporal lobe (contains hippocampus)
What do neurologic changes due to hypoxia depend on?
Extent and duration of the hypoxia
- severe deficits can be cleared completely if hypoxia is revered quickly
How long might sx dt hypoxia take to resolve?
One year, after that unlikely to see additional improvement
- it is the secondary area that is recovering (the part that was damaged by glutamate release)
Is acute hypoxia or chronic hypoxia worse?
Acute is more damaging
What are the four types of stroke?
- Ischemic d/t thrombosis
- Ischemic d/t emboli
- Intracerebral hemorrhagic
- Extracerebral hemorrhagic
Is ischemic or hemorrhagic stroke more likely?
Ischemic – people live longer with more atherosclerosis
Ischemic stroke
- how fast is death
- Main cause
- Death rarely in first hour, more likely to survive than hemorrhage
- Atherosclerosis
Hemorrhagic stroke
- How fast is death
- Main cause for intracerebral and extracerebral
- Death more likely in first hour (than in ischemic)
- Intracerebral: striate arteries rupture (d/t HTN)
- Extracerebral: arteriovenous malformation or aneurysm
Stroke risk factors
- HTN
- smoking
- DM
- HIV tx (elevates cholesterol)
- bruits
- previous TIAs
- Protein C or S deficiency
- Factor V Leiden
- OCP
- fam hx
- age
- a-fib
- AA
With what sx do you workup for stroke?
- HA!
- LOC – only if large bleed
- focal deficits initially unlikely
Sx of intracerebral bleed
- HA only if large
- LOC possible (usually dt uncontrolled HTN)
- always local deficits bc of location
Sx of Ischemic stroke
- HA unlikely
- LOC unlikely
- Large focal deficits dt death of downstream neurons
Cincinnati stroke sx
- Facial droop
- arm drift
- slurred speech
1 sx = 70% likely having stroke
2+ sx = 90%+ having stroke
Infarction
- cause
- vascular thrombosis
- related to pre-existing damage to vessel wall such as atherosclerosis
Infarction
- common location
- common population
- usually preceded by what?
- Common within larger vessels (internal carotid, vertebral, basilar)
- Mostly in older pts
- Commonly preceded by TIAs
What is a TIA
Acute onset of neurologic sx that resolve in minutes to hours
Amaurosis fugax
TIA of visual field
Emboli cause of infarction
- Describe
- Sx
- emboli break off thrombi in left heart or carotid
- Tend to be multiple and involve smaller vessels
- sudden onset of neurological deficit
What do infarction sx depend on?
Location and size of infarct
Infarction sx
- Can be as mild as confusion or a change in bp
- Hard to distinguish from hemorrhage based on presentation or early imaging
How treat infarction?
- TPA w/in 3 hours of focal neurologic sign (and have ruled out hemorrhage)
What is significant about the 3 hour mark for TPA
- cut off for risk of bleed vs. likelihood for improvement.
- might be more willing to give TPA to young person later than 3 hours
- old person wakes up with focal symptoms, not going to give them TPA bc don’t know how long sx started and risk for bleed isn’t worth it
Non-traumatic hemorrhagic stroke
- describe
- commonly associated with what
- not located in a specific part of brain, will expand, doesn’t obey borders
- unlike infarcts, not limited to arterial distribution
- HTN
Non-traumatic hemorrhagic stroke
- type of damage in brain
- compress and disrupt parenchyma vs. destroy it
- may rupture into ventricular system
- herniation may occur secondary to expanding mass
Berry aneurysms
- aka
- how common?
- where occur?
- saccular aneurysms
- 5-6% of population (eeek)
- middle cerebral artery and it’s branches (more often anterior, communicating, and internal carotid than posterior circulation)
Berry aneurysm
- presentation
- usually as spontaneous rupture
- display sx of stroke
- may lead to sudden death
Berry aneurysm tx
- if has a stalk - clip it
- no stalk - coil
Vascular malformations
- how common
- two types
- 5% of population
- venous (more common)
- arteriovenous
Venous malformations
- sx
usually asymptomatic
Arteriovenous malformations
- risk compared to venous
- more likely to rupture
