Head injury 2 - traumatic intracranial haemorrhage Flashcards
Define intracranial haemorrhage
This is a collective term encompassing many different conditions characterised by the extravascular accumulation of blood within different intracranial spaces
What are the different types of traumatic intracranial haemorrhage which can arise ?
Define what an extradural haematoma is
This is a collection of blood between the inner surface of the skull and the outer layer of the dura
Describe the typical presentation of a patient with an extradural haematoma
- Typical presentation is of a young patient involved in a head strike (typically trauma to a temple just lateral to the eye) as a result of sport e.g. rugby or a motor vehicle accident
- The patient may or may not loose consciousness at the time but following the injury they regain a normal level of consciousness, but usually have an ongoing & severe headache, which progressively gets worse
- May take a few hours to days before the bleed presents as decreased GCS, vomiting and fits may be associated. hemiparesis and ipsilateral dilatation of the pupil, patient will then progressively loose consciousness
Bleeding of what blood vessel usually causes an extradural haemorrhage ?
Middle meningeal artery (recall it runs beneath the pterion)
How is a extradural haematoma diagnosed and what investigation is contraindicated?
- CT scan
- LP contraindicated
What are the classic radiological features of extradural haematomas ?
- Typically bi-convex (or lentiform) in shape
- Usually limited by cranial sutures
- Hyperdense & sharply demarcated
- Depending on size their may be features of mass effect (midline shift, subfalcine herniation, uncal herniation)
Define what a subdural haematoma is
It is a collection of blood accumulating in the subdural space (the potential space between dura and arachnoid mater)
What is usually the cause of subdural haematomas ?
It is bleeding from bridging veins between cortex and venous sinuses
- Most are from trauma but the trauma is often forgotten as it is often minor and a long time ago (up to 9 months) - but usually 2-3 weeks
- Subdural haematoma can also be acute and present similar to a extradural haematoma
What are some of the risk factors for subdural haematomas ?
- Elderly are more susceptible
- Falls (epileptics, alcoholics)
- Anticoagulation
Note also any injury associated with rapid change in head velocity may bring movement sufficient to distend and tears these veins.
Describe the typical presentation of a subdural haematoma
- The patients level of consciousness fluctuates which eventually decreases with increasing mass effect and confusion
- Intellectual slowing, sleepiness, headache, personality change and unsteadiness
- Seizures and localising neurological signs such as unequal pupils, hemiparesis develop later on
Subdural haematoma is diagnosed on CT also what are the typical radiological findings seen to distinguish it from other haematomas ?
- Typically crescentic (crescent moon-shaped, concave, banana-shaped) or sickle-shaped
- More extensive than EDH as the occur in the subdural space so arent limited by sutures
- The internal margin paralleling (parallel) the cortical margin of the adjacent brain.
- May be features of mass effect (midline shift, subfalcine herniation, uncal herniation)
Appreciate the difference between extradural and subdural haematomas
What is the treatment of subdural haematomas ?
- 1st line = irrigation and evacuation via bur hole craniostomy
- 2nd line = craniotomy
What is the treatment of extradural haematomas?
- Stabalise and transfer urgently to a neurosurigcal unit for clot evacuation +/- ligation of the bleeding vessel
- Care of the airways in an unconscious patient and measures to decrease ICP often required which include - intubation, ventilation + mannitol
