TBI Intro Pt 1 Flashcards
define a TBI
an injury that disrupts the normal function of the brain. It can be caused by a bump, blow, or jolt to the head or a penetrating head injury
what populations are more at risk for a TBI?
- Children and older adults
- ages 0-3, 15-24 and over 65
- Men > Women 2:1
- Other:
- racial and ethnic minorities
- service members and veterans
- homeless
- incarcareted individuals
- domestic abuse survivors
- rural area dwellers
Causes of TBI
- MVA
- Falls
- Acts of violence
- Sports
Most common causes of TBI based on age
- Children
- falls and abuse
- Adolescents and young adults
- falls, assult, MVA
- Older Adults
- overwhelmingly fall related
2 main categories for brain injuries
Traumatic Brain Injury
Acquired Brain Injury
Mechanisms for Brain injuries
- TBI
- open head injury
- closed head injury
- deceleration injury
- hemorrhage/hematoma
- ABI
- chemical/toxic
- hypoxia
- tumor
- infection
difference between open and closed injury
- Open
- results from penetrating types of wounds
- skull → fractured or displaced
- meninges are compromised
- Closed
- impact to the head but skull isn’t frx
- only cortical neuronal tissue is damaged
- meninges are intact
pathophysiology of primary brain damage from a TBI?
primary brain damage resulting from mechanical issue at time of trauma
can be a focal or diffuse injury
difference between a focal and diffuse injury?
- focal → localized to area under site of impact or site opposite to site of impact
- contusions, lacerations, hemorrhage and/or hematoma
- coup-contracoup injury
- diffuse → diffuse axonal injury (DIA)
Focal Injuries
- Epidural hematomas (EDH)
- Subdural hematomas (SDH)
- Subarachnoid hemorrhage (SAH)
- Intracerebral hemorrage (ICH)
- Contusions
- Coup-contrecoup injuries
describe epidural hematomas
occur between dura mater and skull
- often seen after blow to the side of the head or severe trauma from an MVA
- brief LOC → snap back then rapidly deteriorate
- craniotomies and hematoma evac may be required
describe subdural hematomas
rupture to the cortical bridging veins
- develops betwen the dura and arachnoid
- blood leaks slowly over several hours or weeks
- seen in elderly after falls w/blow to head
- symptoms can be similar to those of CVA
- small clots may be reabsorbed by body, larger ones require surgerical removal
describe SAH
hemorrhage between arachnoid and brain tissue
- most life threatening!
- 1/3 of pts will survive w/good recovery
- 1/3 will survive with disability
- 1/3 will die
- common sequale → vasospasm
describe ICH
hemorrhage within brain tissue itself
- causes → head injury, HTN, AVM
- stroke-like presentation
Coup vs Contrecoup contusions
both are brusing on the surface of brain sustained at time of impact
- coup lesion → same side as impact
- contrecoup → opposite side of brain trauma, a result of deceleration
describe Coup-Contrecoup Injuries
blows to the head cause the brain to “bounce” off of irregular boney prominences on the inside of skull
most common structure invovled:
- anterior poles
- underside of temporal lobe
- underside of frontal lobe
describe DAI
acceleration, deceleration, rotational forces (most common causes MVA)
results in widespread shearing and retraction of damaged axons as well as traumatic micro bleeds
T/F: DIA have a good prognosis?
FALSE
poor prognosis
what is the cause of secondary brain damage during a TBI?
physiological response to initial injury
hypoxic/ischemic injury
swelling/edema
electrolyte imbalance and mass release of damaging neurotransmitters → metabolic cascade → apoptosis
list some causes of non-traumatic brain injuries (aka ABI)
- stroke
- infectious disease
- seizure
- electric shock
- tumor
- toxic exposure
- metabolic disorder
- neurotoxic poisoning
- lack of O2
- drug OD
list some vulnerable areas to anoxic/hypoxic injuries
- hippocampus
- cerebellum
- BG
subtypes of blast injuries that result in TBIs
- Primary → direct effect of blast overpressure on organs
- direct transcranial blast wave propagation
- kinetic energy through vasculature
- increase CSF or venous pressure
- Secondary → shrapnel injury
- Tertiary → direct blow to head
what is a concussion?
a force from a bump, blow or jolt to the head
sustained either directly or indirectly to the body that disrupts normal brain functioning
these forces results in various directional forces inside the skull which initiate a complex pathophysiologic process that alters neurometabolism
symptoms of a concussion
- dizziness
- disorientation
- difficulty concentrating
- sleep distrubances
- nausea
- HA
- loss of balance
- blurred vision and light sensitivity