CNS Trauma Flashcards
Whats a Primary Brain Injury
Occurs at the time of impact, cannot manage/treat this. Main concern is preventing secondary injury
The 3 Brain Bleed Types
- Subdural
- Epidural
- Cerebral (intra-parenchymal)
Cortical Brain Contusion
- Coup/contra-coup injury (brain is injured on two sides, one at the point of contact and the opposite side of the brain as the head moves with the initial trauma)
- Focal Injury - disruption of normal neurological function
- Size of contusion defines extent of injury
Diffuse Axonal Injury
- Most common mechanism is acceleration and deceleration
- Leads to shearing forces of white matter of brain and gross dmg to axons, therefore disrupting impulses
Systemic Causes of Secondary Brain Injury
- Hypoxia
- Increase/decreased CO2
- Anaemia
- Hypotension
- Increased/decreased BM
Intracranial Causes of Secondary Brain Injury
- Seizures
- Cerebral oedema
- Haematomas
- Increased intracranial hypertension (ICP)
Warning signs of increased ICP or impending herniation - treatment
- Decreased GCS
- Development of sluggish /unequal/nonreactive pupils
- Hemiplegia or hemiparesis (unilateralbody paralysis)
- Signs of Cushing’s triad (brady, irregular resps, hypertension)
- Hypertonic solution (CCP) and surgery to releif pressure
Impact Brain Apnoea
A phenomenon where a TBI results in a period of apnoea, can be reversed by assisting ventilations then pt will spontaneously inhale
x3 Layers of Brain
- Dura Mater - Outer layer - extremely tough.
- Arachnoid Mater - can bleed in this area - subdural haematoma
- Subarachnoid Space - Has CSF + large blood vessels. Bleed called subarachnoid haematoma
- Pia Mater - connective tissue
Skull Fracture Types
- Linear (80%) single line fracture
- Depressed - the fracture causes displacement of the bone toward the brain
- Open/closed - skin intact or not
- Basilar - battle sign (behind ear), racoon eyes
The presence of a skull fracture increases the suspicious for intracranial bleed
Dmg to Spinal Cord; Symptoms
- Weakness or paralysis
- Pain, paraesthesia or total loss of sensation
- ParasympethicNS distrupting meaning continual stimulation of vasodilation, bradycardia and warm, dry skin
High/Low Spinal Injuries
High cervical injuries; loss of ability to ventilate
Lower cervical injuries; diaphragm still functions, loss of intercostal muscles
Nerves of Diapgrham and Intercostal Muscles
Diaphragm - C3, C4, C5 keep the diaphragm alive
Intercostal muscles = T2 to 11 keep the intercostals from heaven
Collars
- Adjunct only - doesn’t full immobilise
- Can increase ICP
- Soft collars for non-standard patients
Neuro-Protective Care
- Head up to 20-30 degrees
- No ligatures (loosen collar/tube ties)
- Prevent gagging on adjuncts/instruments
- Analgesia
- Minimise restraint
- Treat systemic causes
