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)
What conditions do we need to avoid for TBI patients?
- Hypotension
- Hypoxia
- Hyperglycemia
- ICP
What is CPP?
Cerebral perfusion pressure = MAP - ICP
What breathing pattern results in decreased ICP?
Tachypnea/alkalosis (inducing hypocapnia)
What is goal MAP in TBI?
> = 80 in order to keep CPP high.
CPP = MAP - ICP
What physical exam triad helps us determine 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?
- 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
What is the physical description of what happens in a concussion injury?
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 CTE and what makes it more likely?
Chronic traumatic encephalopathy: 3+ concussions (football)
How long does it typically take to recover from concussion?
Around 6 days
What is the treatment for a linear skull fracture?
Generally just obs
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
What bone is most commonly affected in a basilar skull fracture?
Temporal bone trauma
What are the hallmark signs of a basilar skull fracture?
- Halo sign (CSF + blood)
- Raccoon eyes
- Battle sign (under the ear)
What is the treatment for an elevated skull fracture?
IV ABX + surgery
What is the ABX for all open fractures in general outside of da hospital?
2g ancef/cefazolin
If we suspect a skull fracture, what additional scans should we order?
- Noncon CT brain and Cspine
- Con CT chest + abd + pelvis
What should you never place in a patient with a basilar skull fracture?
Nasal airway, as the cribiform plate could be fractured.
What is the MC type of traumatic intracranial mass lesion?
Subdural hematoma
Usually due to vein tearing
What are the 3 classifications for SDH?
- Acute <= 2 days
- Subacute <= 3-21 days
- Chronic > 21 days
Darker on CT = older
What gender is SDH MC in?
Males
If a patient has a new type of HA, what imaging should be considered ASAP?
CT head w/o con
What is the criteria for surgical intervention of acute SDH?
- Symptomatic
- Bleed thicker than 10mm
- Midline shift > 5mm
- GCS decrease >= 2
- Fixed or dilated pupils
Craniotomy
When is surgery indicated for chronic SDH?
- Risk of herniation
- > 10mm thickness or 5mm midline shift
- Anyone that has the potential to recover
Burr holes to relieve
What are the 4 types of brain herniation?
- Trans calvarial (going laterally)
- Transtentorial (towards center?)
- Tonsillar (downard)
- Subfalcine (upward/towards face?)
What is the MC type of brain herniation?
Uncal transtentorial herniation
What is the common presentation of brain herniation?
Ipsilateral fixed pupil
What is the primary cause of a epidural hematoma?
Middle meningeal artery rupture
What does an epidural hematoma look like on CT?
Lens shaped
What is the mnemonic for epidural hematoma S/S?
- Epidural hematoma
- Luc E (lucid interval)
- Looks like an Eye on CT
- Middle meningEEEal artery
What is the treatment for epidural hematomas?
- Surgical evacuation
- Monitoring with serial CT scans
What is the classic symptom of SAH?
Thunderclap headache/worst HA of their life
What are the S/S of a SAH?
- N/V
- Nuchal rigidity
- Back pain
- BL leg pain
- Seizures
- Sudden LOC at onset
What is the first step in working up a SAH?
CT w/o con
When would we do an LP for SAH and what would we see?
- Neg CT
- Increased opening pressure
- Increased RBC count in all tubes
- Xanthochromic (yellow) CSF
What is the gold standard imaging for a SAH?
CTA of Brain
What meds do we use to reduce MAP < 130 in SAH?
- Esmolol
- Labetalol
Short half-lives
For a patient with increased ICP and SAH, what interventions do we do?
- Intubate and hyperventilate to REDUCE PCO2 to 30-35.
- Consider mannitol to reduce ICP
- Lasix to reduce IVP
- Surgical clipping/coiling of aneurysm
- Neuro ICU
What is the can’t miss condition in spinal cord injuries?
Cauda Equina syndrome
What is the most commonly injured area of the spine?
Cervical
What is NEXUS criteria used for?
Determination of whether a C-spine injury requires imaging
What is the NEXUS criteria?
- Midline posterior Spinal tenderness present
- Painful distracting injury present
- Intoxication present
- focal Neurological Deficits present
- Encephalopathy (or ALOC) present
All must be negative to clear a patient without imaging.
SPINE
What exam should we not neglect in testing the spinal cord’s motor function?
DRE to test sphincter tone
For significant trauma, what CTs do we order?
- Brain
- C-spine
- Chest w/ con
- Abd/Pelvis w/ con
Con for organs
Can add thoracic and lumbar if needed.
Cranium to coccyx
How do we treat a C1/atlas fx?
Rigid-C collar
Often associated with a C2 facture and without deficits
How do you treat torticollis/C1 rotary subluxation?
- Pain control
- Restrict motion with SOFT collar
- Refer
Soft collar because we don’t want to forcefully correct it.
What are the two types of a C2 facture?
- Odontoid fx
- Posterior element/hangman’s
What is the most common cervical fx in adults?
C5
What is the most stable part of a vertebrae?
Anterior
How do thoracic fx typically occur?
- Anterior wedge/compression: Axial loading with flexion
- Burst/chance/fracture = dislocation
How do you manage anterior wedge/compression of the thoracic spine?
TLSO brace and pain meds
What is the treatment for a spinal cord injury?
- Restrict via rigid c-collar
- No backboard
- IV fluids
- Pain meds
- Transfer
What S/S might suggest cauda equina syndrome?
- Saddle anesthesia
- Urinary retention
- Difficulty walking
- LBP
- Poor rectal tone
- Change in bowel or bladder in anyway
What scan should we order for cauda equina syndrome?
MRI
