Head Injuries Flashcards
What are three ways that you can classify head injuries?
- by mechanism (how did it happen): open or closed
- by severity: mild, moderate, severe
- by morphology: skull fractures, intracranial lesions
What are some examples of closed head injuries?
falls
automobile accidents
assaults
sports
What are some examples of penetrating head injuries?
gunshot wounds
stabbings
What should you do in the ER if a patient comes in with a penetrating head injury?
leave the object in place while you get a CT scan
**this will allow you to see where the object is in relation to large vessels in the brain
A Glascow coma score of 14-15 is (blank)
A Glascow coma score of 9-13 is (blank)
A Glascow coma score of 8 or less is (blank)
mild; moderate; severe (comatose)
**highest GCS score is 15
lowest is 3
What should the Glascow coma score be combined with to establish a neurological baseline?
eye/pupil exam
When should you test a patient by looking at their pupils and getting their GCS score?
after BP and O2 are normalized
before sedative/paralyzing meds given
T/F: A higher GCS score corresponds to a higher chance of death.
False; higher GCS score, lower chance of death
What are the three components of the GCS score?
- eye opening
- motor response
- verbal response
When evaluating eye opening in the GCS, what does a 4 indicate? 3? 2? 1?
4 = eyes open sponataneously 3 = eyes open in response to speech 2 = eyes open in response to pain 1 = no response
When evaluating motor response in the GCS, what does a six indicate? 5? 4? 3? 2? 1?
6 = obeys commands 5 = localizes when touched 4 = withdraws when touched 3 = abnormal flexor response 2 = extensor response 1 = no response
Rank verbal response from 5 (max score) to 1 (min score)
5 = oriented 4 = confused conversation 3 = inappropriate words 2 = incomprehensible sounds 1 = no response
4 things you can check for when you look at a patient’s eyes?
- pupil response - pupils constrict with light
- corneal reflex (in response to Qtip)
- dolls eyes (if neck OK) - eyes remain centered = not good
- oculovestibular reflex - ice water in ear, no nystagmus = no good
Two types of skull fractures?
vault (over the brain)
basilar (under the brain)
Two types of intracranial lesions?
focal (subdural/epidural)
diffuse (concussions, diffuse axonal injury)
Vault skull fractures occur over the brain. Four ways to describe vault fractures?
linear or stellate
depressed or non depressed
Best imaging for a skull fracture (vault or basilar)?
CT scan
This may feel like a depressed skull fracture; may have a soft center and hard edges; need CT to see if there is a fracture present
hematoma
What 2 things can occur with basilar (under the brain) fractures?
CSF leakage (10%) Cranial nerve palsy (facial nerve) (5%)
Which type of basilar fracture, longitudinal or transverse, is most likely to injure the facial nerve?
transverse
What are these clinical signs associated with?
pneumocephalis (presence of air or gas in the cranial cavity) CSF leakage from nose or ear cranial nerve damage hemotympanum Battle's sign racoon eyes
basilar (beneath the brain) skull fracture
What causes racoon eyes?
basilar skull fracture; ecchymosis - blood escaping into the soft tissue
10% of basilar skull fractures present with this
treated with bed rest and head elevation
usu stops in 85% of patients
antibiotics not advised
CSF leak
**if persistent leakage, lumbar drain indicated
What does a halo sign on the pillow indicate? (yellow ring with bloody center; draining from the ear or nose) What should you test the fluid for?
a CSF leakage; test for glucose and beta-2 transferrin (protein found uniquely in CSF)
Frontal basilar fractures will most often present with (blank), while temporal bone basilar fractures will often present with (blank)
racoon eyes; Battle’s sign
What is the most common cause of traumatic subarachnoid hemorrhage?
trauma
T/F: traumatic subarachnoid hemorrhage has a low risk for deterioration or surgical intervention
True
4 types of focal brain lesions?
- epidural hematoma
- subdural hematoma
- contusions
- intracerebral hematoma
What is the difference between an epidural and subdural hematoma?
epidural: above the dura; between the dura and the skull
subdural: below the dura; between the dura and brain
What are epidural hematomas commonly due to?
arterial bleeds (middle meningeal artery); can also be from a vein or venous sinus
What do epidural hematomas look like?
lenticular shape (lens like)
Most common location for an epidural hematoma? In children?
temporal fossa; posterior fossa in children
What usually causes subdural hematoma? What is its shape?
tearing of veins or brain lacerations; shape is not lenticular but more spread out
Compare the shape of epidural and subdural hematomas. Compare the prognosis.
epidural: lenticular
subdural: diffuse
epidural: better prognosis
subdural: worse prognosis due to associated brain injury
How does a chronic subdural hematoma present?
weeks - months after head injury you will get headache, focal neuro deficits and decreased level of consciousness
**better prognosis that acute subdural hematoma
Bruising of the brain; usually due to coup-contrecoup pattern (frontal occipital)
contusions
What should you do with patients who have a contusion?
observe the patient in the ICU; monitor ICP unless the patient is responsive/cooperative; repeat CT in 24 hours (watch out for hematomas)
Why should you do a repeat CT after 24 hours if a patient has a contusion?
risk of hematoma development
What type of lesions are seen on CT with a contusion?
salt and pepper lesions
When should you use surgical evacuation on a patient with intracerebral hematoma?
if there is a significant mass effect (CT); if no significant mass effect, conservative management (intensive monitoring and serial imaging)
short loss of consciousness or temporary neurological dysfunction
concussion
loss of consciousness from time of injury beyond 6 hours
May be mild, moderate or severe
**Severe– deeply comatose for prolonged periods of time and often remain severely disabled if they survive
diffuse axonal injury
What is diffuse axonal injury? Where does most tearing occur in diffuse axonal injury?
trauma causes axons to undergo twisting and tearing; at the gray-white matter junction
What percentage of “mild” traumatic brain injuries deteriorate unexpectedly?
3%
What determines the severity of head injury in a concussed patient?
symptoms and duration of symptoms
Consists of 2 events- days, weeks or minutes apart
Athlete with post-concussive symptoms after HI
Returns later to play and sustains a second head injury.
Loss of autoregulation
Dilated blood vessels
Diffuse cerebral swelling
Increased ICP
brain herniation and death often occur.
Rare, usually young healthy athletes
second impact syndrome
This can occur with repetitive head injury
chronic traumatic encephalopathy
3 options for treatment of TBIs?
- send them home
- admit for 24 hour observation
- transfer to neuro trauma center
GSC 15
Patient alert
CT scan normal
What to do?
discharge patient with head injury warning instructions
admit if coagulation or other problems present
GSC 15
Patient alert
CT scan abnormal
What to do?
if indication for surgery: transfer to neurotrauma
if no indication for surgery: observe for 24 hours, consult neurotrauma, repeat CT scan before discharge
GSC 15
Patient alert
With risk factors: headache, vomiting, focal neurological deficit, seizure, etc
What to do?
treat like category 3
CT scan mandatory
admit patient
What percentage of patients with moderate TBI will deteriorate to coma? Death rate?
10%; 9%
What percentage of severe TBI patients (GCS <8) die?
35-40%
What could hypotension be due to following a brain injury?
severe blood loss
spinal cord injury
cardiac contusion/tamponade
tension pneumo
T/F: A patient’s neuro exam is meaningless if they are hypotensive; can go from unresponsive to near normal after BP is restored
True
3 factors associated with a poor outcome after CT?
- hypotension
- age 40+
- decerebrate motor posture
When should ICP monitoring be used? What is normal ICP?
if the patient is not following simple commands; 10mm (20 is OK)
Which is more useful, CCP (cerebral perfusion pressure) or ICP?
CCP (should be >60mm)
3 things to do when treating increased ICP (>20mm)?
make sure neck is in neutral position
check calibration system
transducer at level of foramen of Monro
How to treat increased ICP (>20mm)?
drain the ventricles with a catheter hyperventilation (reduces intracranial blood flow) hyperosmolar therapy (manitol and hypertonic saline)
What is another, more dramatic thing you could do to treat increased ICP?
decompressive hemicraniectomy (remove from the frontal to occipital bone on one side)
Should steroids be used in cases of increased ICP? What about anti-seizure meds?
NO!!!; Ok
How long is mannitol usu effective?
48-72 hours