Lecture 2: Brain Injury Flashcards
Brain damage caused by events AFTER birth (not congenital or genetic)
Aquired brain injury
An anoxic brain injury is what?
* Is it genetic or aquired?
Anoxic brain injury - happens when the brain is deperived of oxygen
* Think something like cardiac arrest, stroke, tumor, infection all causing some kind of brain injury
Its Aquired
Alteration in brain function caused by an external force
Traumatic Brain Injury
* Evidence of brain pathology caused by an external force (think blunt force)
Multiple systems involved, leads to secondary impairment. Think getting a lascerantion the impacts the integumentary system as well as the brain
Example of a Mild Traumatic Brain injury
Concusion
* Common: atheletes - incidence highest in female atheletes
Motor vehicle releated accidents often lead to what kind of TBI?
Moderate/Severe
What scale is commonly utilized w/ traumatic brain injury?
Glasgow coma scale
What are the 2 leading causes of brain injury associated hospitilizations?
1) Falls (ederly) - most at risk greater than 75 years old
2) Motor vehicle releated incidents
NOTE: Individuals who survive TBI often experience persistent morbidity, with reduced participation and productivity driving the need for ongoing supports for them and their familys
Penetrating break in the skull is open or closed TBI?
* What are breached?
* What is exposed
* Is it focal or diffuse?
Open
Meninges are breached
Brain exposed
Focal injury (we can pinpoint it)
* Focal = releating to center or point of interest
NOTE: This can lead to vascular injury
Non-penetrating, no skull fracture or laceration on brain
* Open or closed
* What often causes this?
* Is it focal or diffuse?
Closed
Coup/Countercoup
* This is that sloshing of brain back and forth
* Often happens in MVA
Can be both focal and diffuse
KNOW: Subarachnoid and subdural hemorrhage can occur w/ diffuse injury
Coup/Contercoup
Primary TBI (this is the first thing that happens)
1) Brain tissue contacts an object - typically open injury
* Penetrating injury
* Leads to: contusions, lacerations, hematomas
2) Rapid acceleration/deceleration - typically closed injury
* Shear, tensile and compression forces
* Diffuse axonal injury (DAI), tissue tearing, hemorrhages
This can all trigger a metabolic cascade
NOTE: Primary traumatic brain injury occurs at the movent of impact and is the direct result of an external force aplpied to the head.
Secondary = Physiological and biochemical changes that occur after the inital injury. This can include swelling, increased intracranial pressure, and inflammation, which may lead to further damage to cels over time.
Diffuse axonal injury, tissue tearing, hemorrhages typically happen w/ open or closed TBIs?
Closed
* do to that coup/counter coup
Cell death due to secondary effects of hypoxia and hypotension, ischemia, edema and elevated intracrainial pressure changes
Secondary injury
Happens after some primary TBI
Blast injury is made up of a primary, secondary, and tertiary response. Explain what each is for this varient of brain injury
1) Primary: Direct effect of overpressure from blast
2) Secondary: Shrpnel contracting person
3) Tertiary: person thrown backwards
Moving of that intracrainal pressure is going to create a herniation somewhere (the brain needs to go somewhere when pressures change)
* often downwards herniation through foramen magnum
* can also affect arteries supplying cerebrum
Which of the following causes a primary injury releated to TBI
* Cell death due to hypoxia
* Brain tissue contacting an object
* Formation of a gematoma
* Diffuse axonal injury
Brain tissue contacting an object
NOTE: If its a closed injury that axonal injury happens after that coup countercoup (brain is sheared back and forth)
What space is between the skull and the dura matter?
Epidural space
What space is between the skull and the brain?
Subdural
Space within the skull
Intracerebral space
What is a contusion?
Bruise in the brain
What is a Hematoma?
* What are the three kinds?
Pooled blood outside a blood vessel
1) Intracerebral
2) Epidural
3) Subdural
What is a hemorrhage
* Our 3 kinds
active bleeding / burst vessel
* can be intracerebral
* Subdural
* Subarachnoid
KNOW: Vascular injury can lead to ischemia/infraction/stroke
Vascular injury can lead to changes in intracrainal pressure
* Brain can be displaced
* Intracrainial pressure increased (because the brain is pushed more over to one side)
Hypotension is #
* What can this often cause?
Systolic BP less than 90 mmHg occuring between injury aand resuscitation can occur
Can often cause hypoxia