(Enochs + some)Lecture 5: CNS Trauma Flashcards
What is a TBI?
Traumatic brain injury, which is an alteration in brain function.
What is a primary brain injury?
The insult that caused the TBI.
- Explosion
- MVC
- Penetrating head trauma
- etc
What is a secondary brain injury?
The cascade of molecular injury mechanisms initiated at time of trauma and continues. (Neuronal cell death)
electrolye imbalances, mitochondrial dysfunction, apoptosis, scondary ischemia from vasospasm, ect
What conditions do we need to avoid for TBI patients?
- Hypotension
- Hypoxia
- Hyperglycemia
- ICP
What is CPP?
Cerebral perfusion pressure = MAP - ICP
What two things result in decreased ICP?
- Tachypnea/alkalosis (inducing hypocarbia)
- HTN
causes vasoconstriction and therefore decreases ICP
What is goal MAP in TBI?
- > = 80 in order to keep CPP high.
CPP = MAP - ICP
What physical exam triad helps us determine increased ICP?
Cushing reflex:
- HTN
- Bradycardia
- Decreased respiratory drive
HIB
HTN
Irregular breathing
Bradycardia
What happens to ICP in TBIs?
Increases, so we need to increase MAP to counteract it.
CPP = MAP - ICP
For a patient with increased ICP, what can we do to help lower it?
6
- Elevate patient head
- Glucose between 80-180
- Prevent any fever (96.8-100.4)
- Keep O2 > 90%
- IV Lorazepam to treat seizures
- IV phenytoin to prevent seizures (esp. for GCS < 10)
What is the trimodal age group for TBI?
- 0-4
- 15-24
- > 75
What is the ABCDE for trauma?
- Airway (C-spine and maintain airway)
- Breathing (ventilation)
- Circulation (pulses)
- Disability (GCS, neuro)
- Exposure (undress pt and check injuries)
A patient that can communicate clearly is already cleared A-D
What are the 3 severity ratings for GCS?
- Mild = 13-15
- Mod = 9-12
- Severe = 8 or less
If it’s 8, then you intubate (mnemonic)
Most TBIs are mild (75%)
What is the inclusion criteria for Head CTs?
- Age 16-66
- Not on blood thinners (except baby asa)
- No seizure after injury
What are the 4 high risk criteria that prompt a Head CT for head trauma?
- GCS < 15 2 hours post injury
- Suspected/confirmed skull fracture
- Signs of basilar skull fracture
- > = 2 eps of vomiting (brainstem injury)
What are the 2 medium-risk criteria that prompt a Head CT for head trauma?
- Retrograde amnesia >= 30 mins prior to TBI
- Dangerous mechanism (hit by car as a pedestrian, ejected from car, fell from >3 ft or 5 stairs)
What criteria is used for determing Head CT criteria for children < 16?
PECARN
How does a concussion typically present in terms of S/S?
- Loss of memory prior to event
- Confusion
- HA, N/V, dizziness
- Visual changes
- LOC (rare)
- AMS
Any neurological symptom can techincally occur
How does a concussion injury look like?
Coup contrecoup injury
What are the more alarming S/S in a concussion?
- Focal neurologic deficit
- Visual field deficit
- Pupil abnormality
- Horner syndrome
Stroke can be caused by traumatic hemorrhage
What is the ED treatment in a concussion
- no less than 2 hr of obs after injury in ED setting and 24 hrs at home.
- any change in neuro status = CT brain w/o
rest, no studying/TV/exercise or ETOH. NO NSAIDS.
what indicates need for admission in Concussions
6
- GCS <15 at 2 hours post injury
- Abnormalities on CT if obtained (at hospital with neurosurgery)
- Seizure
- Bleeding disorders or on anticoagulants
- Recurrent vomiting
- No family or friends able to observe for 24 hours
What is CTE and what makes it more likely?
Chronic traumatic encephalopathy: 3+ concussions (football)
presents w short term mem loss, early dementia, impulsive behavior and depression
How long does it typically take to recover from concussion?
Around 6 days
What is post concussive syndrome
vage neuropsych s/s starting 7-10 days after injury that end within a year of injury.
get MRI if s/s are disabling.
What is the treatment for a linear skull fracture?
obs 4-6 hrrs in ED and dc w/ 24 hr obs if no s/s.
Little to no clinical significance
What is the treatment for a depressed skull fracture?
- Usually open, so give tetanus + ABX (vanco + rocephin)
- If it is greater than the skull’s thickness, surgery
- Consult neurosurg
usually open because when youre depressed you open up to people
What bone is most commonly affected in a basilar skull fracture? what is the tx for this?
- Temporal bone trauma
- admit ALL pts with this
- surgery for underlying bleeds, look for CSF leak from ear/nose
What are the hallmark signs of a basilar skull fracture?
- Halo sign (CSF + blood from ear/nose)
- Raccoon eyes
- Battle sign (under the ear)
- haemotympanum
- bump on head
What is the treatment for an elevated skull fracture?
IV ABX + surgery