Head Injuries Flashcards
1
Q
Stats
A
- TBI is 4th leading cuase of death in US, leading cause in people aged 1-44
- 50% of all trauma deaths are secondary to TBI, 35% of these are dt GSW to head
2
Q
When does neuro injury occur
A
All neuro damage does not occur at moment of impact (primary injury), often evolves over ensuing minutes, hours, days (secondary brain injury)
3
Q
Primary vs. secondary head trauma
A
- Primary injury: irreversible cellular injury dt direct result of injury, only way to avoid is to prevent the event
- Secondary injury: damage to cells that were not initially injured, occurs hours to weeks after primary injury. Goal: prevent hypoxia and ischemia
4
Q
Critical steps to head trauma
A
- Early recognition of TBI by public
- Early recognition of TBI by EMS
- Dispatch appropriate EMS
- Early intervention by EMS
- Appropriate hospital by EMS
5
Q
Prehospital treatment of head trauma
A
- CAB, O2, IVs, C-spine
- Assess and document pupil size and light reflex
- Document duration of pupillary dilation and fixation
- ID hypotension (SBP <90 mmHG)
- ID hypoxia: O2 sat <90%
- Evidence shows raising bp in hypotensive pts with severe head injury improves outcome
- Goal: get pt to hospital that has the right resources in a reasonable amount of time
6
Q
Monro-Kellie Doctrine
A
If have a brain bleed, body can compensate for a while, as mass expands, start to herniate and ICP increases
7
Q
Cerebral perfusion pressure
A
- CPP = MAP – ICP
- Normal ICP is 10-15 mmHG or less
- Goal: maintain CPP ≥ 70 mmHG **
- Maintaining adequate CPP is more important than keeping normal ICP value
8
Q
Cerebral Blood Flow
A
- Brain uses 20% of O2 consumed and 15% of resting cardiac output
- Remains constant over wide range of arterial pressures, if MAP >150, increased cerebral blood flow, if MAP <20 then CBF ceases
9
Q
Cerebral imaging
A
- CT scan: NO contrast is gold standard (assume since have TBI prob have c-spine injury so do CT of neck too)
- Plain films: not used much any more
- MRI: not used in acute situations unless known spinal cord trauma
- US: more of a brain death exam, not for acute analysis
10
Q
Skull fracture
- linear and simple comminuted
A
- Explore wound
- Prophylactic abx?
- Occipital = high incidence other injury
- If depressed beyond outer table = NS repair
11
Q
Skull fracture
- Basilar
A
- Petrous portion of temporal bone
- Results in dural tear: CSF otorrhea/rhinorrhea, battle sign, raccoon eyes, hemotympanum, vertigo, hearing loss, seventh nerve palsy
- Do start prophylactic abx (Ceftriaxone)
12
Q
Brain Lesions
A
- Caused by increasing amts of acceleration-deceleration or torsional forces
- MC type of TBI
13
Q
Brain lesion
- s/sx
A
- LOC, AMS, amnesia (retrograde or post traumatic), disorientation, sleepiness, abnl coordination or balance, abnl reaction time, poor concentration and comprehension, opposition or other behavior change, diplopia, incontinence
- On the field: vacant stare, lack of coordination, poor performance, wrong huddle, distracted, inappropriate behavior, slurred speech
14
Q
Types of brain lesion
A
- Mild concussion
- Cerebral concussion
- Diffuse axonal injury (DAI)
15
Q
Mild concussion
A
- Consciousness is preserved
- Noticeable degree of impaired neuro dysfunction
- Often go unnoticed
- Confusion/disorientation with slight anterograde/retrograde amnesia
16
Q
Cerebral concussion
A
- LOC + some amnesia
- Return to full consciousness within 6 hrs of injury
- Usu no sequelae
- Some suffer post-concussion syndrome
17
Q
Diffuse axonal injury
A
- Prolonged posttraumatic coma not dt mass lesion or ischemia, persistent vegetative state
- Disruption of axons in white matter and brainstem
- Occurs immediately, is irreversible
- Common after MVC and shaken baby syndrome
- Motor posturing and autonomic dysfunction
- Normal CT initially
- MRI shows multiple, diffuse abnormalities
18
Q
Tx
- concussion
A
- Serial neuro evaluations Q2-3 hours
- Avoid sedating medications: narcotics, alcohol, antihistamines
- Yes: ICE, Tylenol, light diet
19
Q
Post concussive sx
A
- At 3 months post injury, 20-40% have post concussive syndrome
- Neuropsychiatric impairments: attention, concentration
- Somatic complaints: HA, fatigue, dizzy
- Affect: depression or anxiety
20
Q
Secondary Impact syndrome
A
If receive second injury after first injury has healed, lose ability to regulate pressure in brain and can herniate and die
21
Q
Return to play after concussion
A
- No sports for 5-7 days
- Should f/u with PCP or neurologist before RTP
- Must be asx for a week before RTP
22
Q
Impact program for concussions
A
- Computer test that can be administered by coach, trainer, medical provider to measure baseline and post injury performance.
- Measures attention, memory, processing speed, reaction time
- Measures cognitive function: attention span, working memory, sustained and selective working time, response variability, non-verbal problem solving, reaction time
- Post-concussion testing within 24-72 hours of injury
23
Q
Focal brain lesions (4)
A
- epidermal hematoma
- Subdural hematoma
- traumatic SAH
- Contusion
24
Q
Epidural hematoma
A
- Blunt trauma to temporoparietal region
- 80% associated with skull fracture
- Usu middle meningeal artery under the temporal bone
- May experience a “lucid interval” and then crump
- Tx: acute craniotomy with sx drainage
25
Subdural hematoma
```
• Tearing of veins
• Sudden acceleration-deceleration injury
• Common in elderly and alcoholics
• Acute, sub-acute, chronic
- Acute < 2 weeks
- Chronic >2 weeks
```
26
Traumatic SAH
* MC CT finding in moderate to severe TBI
* HA, photophobia, meningismus
* Early SAH triples mortality
* CT: can see blood inside gyri
27
Four types of brain herniation
* Uncal transtentorial
* Central transtentorial
* Cerebellotonsillar
* Upward posterior fossa
28
How to select a hospital for head trauma care
- Trauma center preferred
- Want immediate dx and interventional capabilities and appropriate medical personnel
- CT scan and operating room
- ICP monitoring capabilities
- ICU
29
Reasons to CT
* LOC or persistent AMS
* Intoxicated
* Other associated injuries
* Poor f/u likely
30
Reasons to not CT
* Alert and awake and not confused
* Reliable family and transportation
* Knowledge and wits to come back if things get worse
31
Tools to use to determine extent of head injury
- Canadian CT head injury/trauma rules for adults
| - PECARD and Pediatric NEXUS II Head CT Decision for Blunt Trauma for pediatrics
32
When to admit head trauma
- GCS < 14 or
- Not CT available or abnl CT
- Penetrating in jury
- LOC or fluctuating LOC
- Severe HA
- Intoxicated
- Skull fx
- Sig associated injuries
- No reliable caretaker
- Not able to promptly return to ED
- Sig amnesia
CSF leak
33
Prognosis for head trauma
- Poorer as GCS decreases
- Inversely proportional to age
- Pupillary findings:
Bilateral worse than single non-reactive pupil (>4 mm is dilated)
34
Head trauma
| - tx
- Aggressive patient resuscitation
- Blood pressure control
- O2
- IV fluids
Goal is euvolemia
- Patient positioning: elevate head to dec ICP
- Sedation: brain injuries cause irritation. Also if have shunt
- Mannitol and Lasix – diuretics, can be used together
- NO STEROIDS
- Anticonvulsants: Keppra MC. Phenytoin or carbamazepine may also be used. (Acute control via diazepam or lorazepam)
- Neuromuscular blockade: paralysis
CSF reduction: ICP monitoring device, release CSF based on ICP
35
IV fluid tx
* Goal is euvolemia
* Isotonic fluids to avoid hyperglycemia
* Non-dextrose containing fluids: dextrose crosses bbb and can cause edema
* Watch for hyponatremia
* Monitor I&Os
* Foley catheter
36
Treatment for intracranial HTN
No specific tx unless signs of herniation or neuro deterioration
37
head trauma pearls
- Scan all elderly heads if any possibility of head injury
- Scan all pts on ASA, Coumadin, Plavix if any possibility of head injury
- Repeat neuro exams (inc pupil exams)
- Don’t hesitate to intubate in a controlled setting if at all worried will lose airway
