The flashcards below were created by user
on FreezingBlue Flashcards.
What are the O2 requirements for cerebral metabolism?
- 2% of body weight
- 20% of CO
- The cerebral cortex is most sensitive to O2 delivery
What does anoxia cause?
Cerebral edema and neuron death
Does the brain need insulin to use glucose?
What is CPP (Cerebral perfusion pressure)?
Mean arterial pressure - mean intracranial pressure=CPP
What is normal CPP?
What is the normal BP goal in stroke patients?
180/100- this gives a good CPP
What should the CPP be in a brain injury patient?
70's (MAP should be at least 75)
What causes increased CBF?
- blood viscosity
What causes decreased CBF?
- blood viscosity
- intracranial HTN
Why is the goal when hyperventilating a patient?
Keep CO2 32-35. This slight decrease is CO2 causes arterial blood vessels to remain normal. (High CO2 dilates the vessels)
What are early signs of increased intercranial pressure?
What cranial nerves controls the tongue?
Nerves 10,11, and 12
What cranial nerve controls the pupil function?
Cranial nerve 3
What do racoon eyes indicate?
Basal skull fracture
What are signs and symptoms of increased ICP?
- 1) Mental status changes
- 2) Pulse pressure widens and HR drops
When assessing respitory what does bradypnea indicate?
When assessing respiratory where in the brain does Chine-Stokes respirations indicate damage?
When assessing respiratory where in the brain does hyperventilation indicate damage?
lower midbrain or upper pons
When assessing respiratory where in the brain does amnestic respirations indicate damage?
mid to lower pons
When assessing respiratory where in the brain does ataxic respirations indicate damage?
What is good to remember in a central fever?
Temps will not decrease with medications
What is a central fever caused by?
Injury to the hypothalamus
What should you do with a patient with a GCS of 8 or less?
What pupil abnormality is normal in light colored eyes?
One pupil is larger than the other
What is cushing's triad?
- A sign of increased intracranial pressure
- Progressivly increasing SBP
- widening pulse pressure
What are the phases of decompensation with increased ICP?
- 1- mental status changes
- 2-pulse pressure and HR changes
- 3-pupilary changes (small and sluggish)
What are complications of Increased ICP?
- Ischemia and edema
- Diabetes Insipidus/SIADH
- DVT/Stress ulcer
- Respiratory insufficiency
What is hydrocephalus?
Excessive accumulation of CSF causing increased ICP
What causes hydrocephalus?
- Acquired-communicating--CSF blocked and leaving ventricles (open)
- Non-communicating- obstructed
- Ex-vacuo- stroke or traumatic injury cause brain damage
What causes normal pressure hydrocephalus?
- Most common in the elderly
- Caused by: Subarachnoid hemorrhage, head trauma, infection, tumor or complications of surgery, idopathic
What is muscular dystrophy?
- Genetic disorder
- Complications include- CMP, decreased mobility, over all muscle weakness, respiratory compromise, scoliosis, nurtional and swallowing abnormalities, falls
What is Guillain-Barre syndrome?
- Inflammatory peripheral neuropathy
- Autoimmune response is most suspected, possible infection
- Myelin sheath around the axon is lost
- respiratory compromise
What is Myasthenia gravis?
- Neuromuscular transmission disorder
- Autoimmune response
- Anticholinesterases, steriids, Mestinon
- ThymectomyRespiratory comprimise
If LP fluid is cloudy with low BS then think:
How should serum BS and CSF BS compare?
They should be the same
What are symptoms of a brain contusion?
partial or complete dysfunction for less than 24 hours, petechial hemorrhages, lacertion may occur, areas of infarction and necrosis may occur=edema, IC HTN
What are sympotoms of a concussion?
- Transient state of partioal or complete paralysis of cerebral functioning with complete recovery within 12 hours, Headache
- Mild= no loss of consciousness or memory loss
- Classic= loos of consciousness or memory loss
What can be expected with a difuse brain injury?
- loss of consciousness more than 24 hours and axonal disruption
- amnesia, residual deficits in memory
What can be expected with a difuse axonal injury?
- Severe mechanical disruption of axons and neuronal pathways in both cerebral hemispheres, diencephalon and brainstem
- Not going to recover
Where is the most common place for a blood clot in the brain?
Mid cerebral artery
What are the cardinal findings in brain death?
- Coma or unresponsiveness
- absence of cerebral motor responses to pain in all extremities
- absence of brain stem reflexes
What tests are done to declair a patient as brain dead?
- Cerebral angiography
- Transcranial doppler
- Somatosensory and brain stem auditory evoked potentials
- Technetium Tc 99m brain scan
Usually venous bleed, accumulated below dura mater
What are the different classifications of SDH?
- Acute SDH- clinical indications occure within 24 hours
- Subacute SDH- within 2 weeks
- Chronic- weeks to months