head trauma/ brain injury

Question 0

Identify and discuss skull fractures

Answer 0

Base of skull fractures can be associated with underlying cranial nerve and vascular injuries
Signs and symptoms
-Combativeness, agitation
-Racoon eyes (bilateral eyelid bruising)
-Battle sign (behind the ear bruising)
-CSF leak
Do not insert NG tube

Question 1

Differentiate between primary and secondary brain injury

Answer 1

Primary brain injury is caused at the time of the impact, it can be focal or diffuse (tension, stretching and shearing of brain tissue usually causes by rotational acceleration/deceleration movement).
Secondary brain injury is what medical/nursing staff try to prevent as it occurs after the initial insult and is caused by hypoxaemia, hypercapnia, hypotension, raised ICP, hypo/hyperglycaemia and infection.

Question 2

Discuss management of pt with head injury

Answer 2

• • hypertonic saline/mannitol
• Diuretic: frusemide
• Anticonvulsant: phenytoin, phenobarbital and diazepam (if have seizure)
• Antibiotics (fracture)
• Sedatives ( with care in head injury as don’t want to mask raised ICP)
• If sedated or paralysied patient will require HDU or ICU
• May require surgery : evacuation or clips
• Need to consider: nutrition (increased metabolic rate), temperature regulation, speech, continence, skin integrity, psychosocial care, DVT prevention.

Question 3

Define and discuss Concussion

Answer 3

Define and discuss Concussion
Is caused by a violent jarring or shaking (such as blunt trauma or acceleration-deceleration called contra cue) that results in a disturbance of brain function.
Signs and symptoms:
-ACS +/- LOC
-Dizziness, drowsiness, confusion, retrograde amnesia
-Vomiting, combativeness, transient visual disturbances
-Changes to vital signs are rare but possible
-Post concussion syndrome: headache, difficulty concentrating

Question 4

Define and discuss cerebral oedema

Answer 4

Cerebral Oedema is swelling of the brain tissue with or without associated bleeding. Can result from metabolic response to an injury, tumour or as result of hypoxia to the brain. Results in marked increases in ICP.

Question 5

Define and discuss cerebral contusion

Answer 5

Bruising of brain in area of cortex or deeper (commonly frontal, temporal or occipital lobes)

• More serious neurologically than concussion due to structural changes
• Can result in LOC or coma for hours to days
• Associated with seizures, hemiparesis, aphasia, personality changes.
• Usually heal on own with improvement over time
• Complication: increased ICP secondary to cerebral oedema.

Question 6

Altered consciousness state and ICP

Answer 6

Discuss causes of Altered consciousness state and ICP
Cerebral causes
•Head injury: oedema, haemorrhage, local or diffuse injury
•Infection: meningitis, cerebral abscess and encephalitis
•Seizure
•Ischaemic event: stroke, Transient ischaemic attack (TIA)
•Drugs and poisons
•Space occupying lesion (blood clot, tumour
Non-cerebral
•Respiratory: hypoxia, hypercapnia
•Cardiovascular: decreased perfusion, fast drop in BP. CPP (MAP-ICP needs to be between 60-80mmHg)
•Metabolic: hypo/hyperglycaemia, acidosis, kidney disease, liver disease
•Other: psychiatric illness (catatonia), hypo/hyperthermia

Question 7

Discuss the management of Altered consciousness state and ICP

Answer 7

Discuss management
•Requires primary and secondary assessment, followed by in-depth focused assessment of the neurological system
Focused
•GCS
•Urgent head CT
•Pathology
•Lumbar puncture (if signs of raised ICP must have head CT first)
•Insertion of ICP monitor – sustained ICP above 20mmHG represents a neurosurgical emergency)

Question 8

Define ICP

Answer 8

Define ICP
ICP is the hydrostatic force measured in the brain CSF compartment. Normal ICP is the pressure exerted by the total volume of the three components within the skull: brain tissue of 80%, blood of 10% and Cerebral spinal fluid of 10%).
Define normal parameters
Normal ICP is under 15mmHg

Question 9

Discuss signs of increased pressure

Answer 9

Discuss signs of increased pressure
Early - altered state of consciousness (restless, agitation, confusion, drowsiness)
- headache
- Nausea and vomiting (important sign)
-? Pupil changes
-? Seizures
Late - urine output above 300ml/hr
- unresponsive
- cushings reflex: HT, widening pulse pressure, bradycardia
- cheyne-stokes respirations (irregular and deep) sign of brain stem compression
- abnormal posturing (feet extended, don’t normally respond to pain, abnormal; flexion)

Question 10

Discuss management of ICP

Answer 10

Aim
-prevent secondary injury such as herniation,
-maintain or optimise cerebral perfusion and keep ICP below 20
•Position at 30-40 degrees head up
•Aim to control seizure activity (sodium)
•Reduce noxious stimuli (adequate sedation, pain management)
•Pharmacological: osmotic diuretic therapy (mannitol)
•Drainage of CSF (external ventricular drain)
•Surgical decompression - craniectomy