Unit 2: CONCEPTS for Traumatic Brain Injury Flashcards
Damage to the brain from an external force not caused by neurodegenerative or congenital conditions
Traumatic Brain Injury
A force produced by a blow to the head is a ____ injury.
Direct injury (GSW, blow to the head, fall)
A force applied to another body part with a rebound effect to the brain is an ______ injury.
Indirect injury
(whiplash, rear-ended MVC, Shaken baby syndrome)
A ______ brain injury occurs at the time of injury and results from the physical stress (force) within the tissue caused by blunt or penetrating force.
Primary brain injury
Primary brain injuries can be further classified into four categories. What are they?
Opened or Closed
Focal or Diffuse
A ____ brain injury is characterized by damage throughout many areas of the brain.
Diffuse brain injury
(Typically microscopic + may not be seen on imaging until necrosis occurs)
An ____ brain injury occurs when the skull is fractured or pierced by a penetrating object.
Open brain injury
A _____ brain injury occurs when the integrity of the skull is intact, but damage to the brain tissue still occurs due to ICP.
Closed brain injury (contusion, cerebral laceration)
A ____ brain injury is confined to a specific brain area and causes localized damage.
Focal brain injury
(often detected w/ a CT or MRI)
A ______ brain injury occurs after the initial injury resulting from physiologic, vascular, &/or biochemical events.
Secondary brain injury
The severity of a TBI can be classified in three ways…
Mild, Moderate, and Severe
_______ is a type of mild TBI caused by a blow to the head and may or may not result in some period of unconsciousness.
Concussion
The most common secondary injury from a mild TBI (concussion) is ________ syndrome where Sxs continue to occur for weeks to months after initial TBI.
Postconcussion syndrome
(HA, impaired cognition, dizziness/vertigo)
The most common secondary injury from a moderate or severe TBI result from (4)
- Hypotension (MAP <65)
- Hypoxia (PaO2 <80 mmHg)
- ICP (NR: 10-15 mmHg; neurons die at >20 mmHg)
- Cerebral edema
Secondary TBI:
Hypotension may be r/t (2)
Shock or clot formation
Secondary TBI:
Hypoxia may be r/t (3)
Respiratory failure, asphyxiation, loss of airway/impaired ventilation
Secondary TBI
Cerebral edema may be r/t (2)
Low blood flow (perfusion) + hypoxemia
Which Secondary TBI has the poorest prognosis?
Cerebral Hypoxia!
As ICP increases, cerebral ______ decreases leading to tissue ischemia and edema.
cerebral perfusion
If cerebral edema isn’t treated, the brainstem may ..
HERNIATE! eeeeeek!!
Is a cerebral hematoma a big deal?
OH yeah! all are considered potentially life-threatening → space-occupying lesion surrounded by edema
What are the 5 S/S associated with a Basilar skull fracture?
- CSF leakage (ears, nose)
- Hemotympanum (blood behind tympanic membrane or external ear if ruptured)
- Ecchymosis (behind ear or periorbital area)
- Loss of smell + hearing (immediate)
- Impaired facial nerve function (immediate or delayed)
Ecchymosis found behind the ear is called
Battle sign
Ecchymosis found behind the periorbital area is called
Raccoon eyes
A “Halo sign” is indicative of
CSF leakage!
If you suspect a brain hemorrhage, what and how often should you assess your patient?
Monitor q 5-10 min for changes in Neuro status!
Call provider or Rapid Response if any changes occur
A loss of consciousness from an epidural hematoma is considered …
a NEUROSURGICAL EMERGENCY!
Bleeding will occur suuuuper fast (pg. 913)
What Sxs might we see for a pt with a Mild TBI (aka concussion) and when do they usually resolve?
Sxs usually resolve w/in 72 hours
1. +/- unconsciousness for = 30 min
2. Impaired cognition (memory, thinking; dazed, disoriented)
3. Post-traumatic HA
4. Post-traumatic vertigo
5. No brain damage evident on imaging
Cerebral Perfusion Pressure (CPP) =
CPP = MAP - ICP
A Cerebral Perfusion Pressure (CPP) <__ is considered an indicator of a poor prognosis r/t a TBI.
CPP <70
Hypercarbia can cause cerebral vasodilation and contribute to increased ___, whereas hypocarbia caused by hyperventilation can lead to ______.
Hypercarbia → Increased ICP
Hypocarbia → Ischemia
A TBI can result in “Autoregulation impairment?” What does this mean?
the ability of cerebral vasculature to modify systemic pressure such that blood flow to the brain is sufficient.
What type of Herniation am I?
Shift of temporal lobe leading to pressure on the oculomotor nerve which causes DILATED, nonreactive pupils.
Uncal Herniation
“Uncle D!”
What type of Herniation am I?
Shift downward toward the brainstem resulting in hemodynamic instability, Cheyne-Stokes respirations, and PINPOINT, nonreactive pupils.
Central Herniation
“Pin the donkey in the Center”
What should we suspect if our pt develops intense thirst and extreme urination?
Diabetes insipidus
-too little Antidiuretic hormone
What should we suspect if our pt has electrolyte imbalances, low Na+ levels, and urinary retention?
Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
-too much Antidiuretic hormone
Criteria for Brain Death (4)
- Coma for known cause
- Normal body temperature
- Normal blood pressure > 100
- Neuro exam- 2 providers
