Neurotrauma Flashcards
What is a Traumatic brain injury (TBI)?
= a form of acquired brain injury, occurs when a sudden trauma causes damage to the brain.
- Can be caused when the head suddenly and violently hits an object or when an object pierces the skull and enters the brain tissue
Anatomy of the brain?
- grey & white matter
- 3 parts = Brainstem, cerebellum, cerebrum
- 4 lobes = Frontal, parietal, temporal, occipital
- R & L Hemispheres
- 12 Crainal nerves
TBI severity (Categories)
Mild = GCS 13-15
Moderate = GCS 9-12
Severe = GCS <8
Three main parts of the brain?
- Brain stem = changes in HR, breathing, BP, Vomiting, swallowing & Digestion
- Cerebrum = intelligence, learning, judgement, speech & memory, hearing, vision, taste & smell, skeletal muscle movements
- Cerebellum = balance, coordination & posture
Pathophysiology of the Brain?
— skull is rigid compartment which holds everything
— Any changes to blood, CSF, Brain, volumes creates pressure build up
— Pressure on the Brain leads to death
What is cerebral blood flow?
— brain has the ability to control its blood supply to match its metabolic requirements
- vasoconstriction and dilation
- CBF increases with
— increase metabolic rate
— Hyperthermia
— seizures
— pain + anxiety
What is cerebrospinal fluid (CBF)?
- purpose = buffer —> thick and buffers the brain through movement (protection
- absorbs
- if blocked = increase of pressure = problem
Types - haemorrhage of the brain
Focal injuries
1. Haematoma
a) Epidural haematoma
b) Subdural Haematoma
c) Subarachnoid haemorrhage
2. Cerebral Contusions
3. Meningitis
Diffused injuries:
1. concussion / mild TBI
2. Diffuse atonal injury DAI
Describe the types of haematomas TBIs?
- Haematoma: haemorrhage of the brain
a) Epidural haematoma (ARTERY) —> middle meningeal artery rupture
— usually due to blow to side of head at pteranodon (thinnest part of skull)
— Rapidly expanding
b) Subdural haematoma (Veins) —> tears in bridging veins that cross the subdural space
— slower symptom onset due to slower nature of bleeding from vein
c) Subarachnoid haemorrhage —> bleeding into the subarachnoid space = raised ICP
What is cerebral contusions?
- Cerebral Contusions —> bruise on surface of the brain
— caused by movement in cranial vault & evolves over time (12-14 hrs to appear on CT)
What is menegitis?
- Meningitis —> inflammation of the meninges of the brain/ spinal cord or both.
Describe concussion/ mild TBI?
- Concussion/ mild TBI
— direct blow
— Diffuse injury
— transient amnesia / LOC
Describe Diffuse atonal injury DAI
- Diffuse atonal injury (DAI)
— Mild-Severe TBI
— Diffuse = microscopic damage
— damages integrity of axon
— ICU ventilated for long period
— MRI diagnosis
Mechanism of injury TBI
— Blunt (common in ED)
— penetrating (bullets, knives)
— MVC
— Falls
— Assults
— Less common:
smoke inhalation, burns, explosion)
What is primary injury TBI?
= injury at time of event
— Primary irreversible injury
— only treatment is prevention of secondary injury —> once damage is done you may not be able to fix
What is secondary injury?
Secondary injury = Follows the initial even (PREVENTABLE)
— e.g. hypoxia, hypercapnia, hypotension (CCP > 60mmHg), metabolic changes
Is concussion a diffuse or focal bleed?
= diffuse
Can diffuse axonal injury be seen on a CT scan?
= no
Is epidural haematoma an arterial or venous bleed?
= Arterial
Is subdural haematoma an arterial or Venous bleed?
= Venous
Can cerebral contusion be seen on a CT scan?
= yes appears over time
After a positive CT scan do all patients need an operation?
= No small bleeds may need to be watched
What are the causes of a secondary brain injury?
— hypoxia
— hypercapnia
— hypotension
— temperature (hypothermia/ hyperthermia)
What is the normal range for ICP?
= >20mmHg
Factors that affect ICP
Factors affecting ICP
- cerebral blood flow
- cerebral venous return
- oxygen
- carbon dioxide blood pH
Preventing Hypoxia?
- Below 8 GCS = intubate
- SPO2 above 90%
- RSI with c-Spine protection
- ensure adequate mechanical ventilation
Prevent hypercapnia?
- causes cerebral vasodilation and increase ICP
- keep patient at normocarbia 35-45 mmhg
- continuous capnography
Prevent hypotension?
- above 90 mmHG
- decrease cerebral perfusion pressure
- decreased oxygenation to cerebral tissue
Prevent Hyperthermia?
- temp increase linked to raised ICP
- ICP falls at temp below 37
- active cooling
Prevent coagulopathy?
- Detect clotting cascade
- worsens injury
- increases with IV fluids
What is the primary survey for TBI?
- Airway & C-Spine stabilator
- Breathing (ensure high oxygenation & consider pneumothorax)
- Circulation (use blood products & inotropes in ICU if needed)
- Disability (AVUP, GCS)
- Exposure (Wounds, bleeding, insert IVC)
- Re-evaluate continuously
What is the treatment for severe TBI?
- Sedation
- Fluid management
- Osmotherapy
- Hypothermia
- Surgery
- hyperventilation
- steroids
What is the treatment for raised ICP?
Treatment to reduce ICP
- Reduce cerebral oedema (osmotherapy)
- promote venous return
- reduce activity associated with elevated ICP
- reduced cerebral metabolic rate
- reduced hyperthermia
- management of pain and agitation
- risk of hypertension
What is the ongoing nursing management of TBI?
Ongoing management
- sedation/ analgesia
- Imaging diagnosis
- monitor MAP
- observe signs of impending
- herniating
Nursing care for TBI?
- GCS hourly consistency
- Head to 30 degrees
- Temperature (high temp = oedema)
- Cervical collar/ clearance
- Cluster care
- Adequate analgesia (prevent ICP)
- DVT prophylaxis
- TEDS
- Calf compressors until fully ambulatory
- Chemical prophylaxis (heparin
- Avoid NSAID/ Aspirin
- Positioning
- Foot splints
- Bed rails / restraint
- Pillows
- Regular passive movement
- Families are important
- Reduced stimulation
- Consistency in routine
- Rest
- Familiar objects/ photos
- Maintain safe distance
- Develop plan
What is the long term treatment for TBI?
Long term treatment:
- promote return to functional and independent life (social, emotional, physical and relationship)
- must be in conjunction with family
Take home messages for TBI?
Take home message:
- regular monitoring
- secondary injury prevention
- reduction ICP
- avoid hypoxia/ hyperthermia
- early rehab
- nursing management
- reduced simulation
- cluster care
