Response to traumatic brain injury Flashcards
Subarachnoid hemorrhage causes damage by:
- Raising ICP
- Direct pressure on tissue
- Depriving downstream tissue of blood
- Vasospams - ischemic injury
- Inflammation of meningies - increase CSF in ventricles - hydrocephalus
Hydrochepahlus =
Dilated ventricles due to CSF
Classic symptoms of subarachnoid
- Nucal stiffness
- Thunderclap headache
- Raised ICP symptoms
Symptoms of subdural can be
Delayed in onset
Symptoms of subdural:
Loss of consciousness
Vomiting
Focal lesion
Headache
Subdural hematoma can lead to what in the brain
Midline shift
Herniation
Concussion is a
diffuse brain injury
Chronic concussions can cause a build up of
Tau proteins in neurones
2 types of injury in concussion
Couo-coutercoup
Torque
Troque injuries can effect
Reticular activating system
What can cause rapid cerebral oedema after concussion
Secondary impact syndrome
Symptoms of concussion
Memory loss
Confusion
LOC
Hematoma =
A collection or clotting of blood outside the vessel.
Types of altered conscious level in response to injury:
- Loss of consciousness
- Post-traumatic amnesia
- Pre-traumatic amnesia
Why should you always ask about memory and LOC around time of trauma?
PTA is an important risk factor for a brain bleed
Primary brain injury =
Occurs during initial insult, mechanical damage
Primary brain injuries can be what?
Focal or diffuse
What can cause progressive brain damage?
Mechanoporation Calcium flux O2 free radicals Cytokine Axotomy
Axotomy =
severing an axon
Secondary injury =
Not caused by mechanical damage. Results from the process initiated by trauma.
Ex of things that can happen AFTER inital injury
Seizures
Infection
Ex of secondary injuries
Raised ICP Hypoxic brain injury Ischemic brain injury Seizures Infection
ICP =
Brain matter + CSF + Blood
Cerebral blood flow is under what?
Autoregulation
Autoregulation acts to
Maintain cerebral blood flow at all times. Vasodilartion and vasoconstriction
Monroe-Kelly doctrine =
Decribes relationship between ICP, blood, brain and CSF. Decribes uncompensated state that is reached when mass reaches a certain size
Initially, what happens when ICP increases
CSF less produced, more absorbed
Vasoconstriction
Normal ICP =
10 mmHG
Abnormal ICP
> 20 mmHg
Severe ICP
> 40 mmHg
Mass effect =
phenomenon in which a focal lesion causes surrounding areas of brain tissue or brain structures to be compressed and injured due to the degree of space that leaking blood, cerebrospinal fluid, or edema takes up within the restricted skull space.
CPP stands for
Cerebral perfusion pressure
CPP =
MBP - ICP
What compensated for increased ICP to maintain CPP
Cushing response
Cushing reflex =
Increase BP to maintain CPP in response to ICP
Head injury will do what to BP?
Increase
To save the brain …
Save the heart
