Raised Intracranial Pressure Flashcards
(26 cards)
What occurs when additional volume is present within the skull?
Raised intracranial pressure
Additional volumes can include haematomas, tumours, and excess CSF.
What is the normal intracranial pressure (ICP) range in mmHg when supine?
7-15 mmHg
What is cerebral perfusion pressure (CPP)?
Net pressure gradient causing cerebral blood flow to the brain
CPP is calculated as mean arterial pressure - ICP.
What are some causes of raised intracranial pressure?
- Idiopathic
- Traumatic head injuries
- Infections (e.g. meningitis)
- Tumours
- Hydrocephalus
What is idiopathic intracranial hypertension classically seen in?
Young, overweight females
What are some risk factors for idiopathic intracranial hypertension?
- Obesity
- Female sex
- Pregnancy
- Drugs (e.g. COCP, steroids, tetracyclines, retinoids, lithium)
What are the features of idiopathic intracranial hypertension?
- Headache
- Blurred vision
- Papilloedema
- Enlarged blind spot
What is one management option for idiopathic intracranial hypertension?
- Weight loss
- Carbonic anhydrase inhibitors (e.g. acetazolamide)
- Topiramate
- Repeated lumbar puncture
- Surgery (optic nerve sheath decompression, shunt)
What characterizes an extradural haematoma?
Collection of blood between skull and dura
Most often caused by low impact trauma, such as a fall.
What is a classic presentation of extradural haematoma?
Patient initially loses, briefly regains, and then loses consciousness again after a low-impact head injury
What imaging characteristic is associated with extradural haematoma?
Biconvex (or lentiform/lemon) hyperdense collection
Limited by suture lines of the skull.
What is a subarachnoid haemorrhage?
An intracranial haemorrhage within the subarachnoid space
What are two causes of subarachnoid haemorrhage?
- Traumatic
- Spontaneous (e.g. intracranial aneurysm, AV malformation)
What are the features of subarachnoid haemorrhage?
- Thunderclap headache
- Nausea and vomiting
- Meningism (photophobia, neck stiffness)
- Coma
- Seizures
- ECG changes (ST elevation)
What is the first-line imaging for subarachnoid haemorrhage?
Non-contrast CT head
What management options are available for subarachnoid haemorrhage?
- Supportive care
- Oral nimodipine
- Coil, craniotomy, or clipping
What are the complications of subarachnoid haemorrhage?
- Re-bleeding
- Hydrocephalus
- Vasospasm
- Hyponatraemia (SIADH)
- Seizures
What is a subdural haemorrhage?
Collection of blood deep to the dural layer of meninges
How are subdural haemorrhages classified based on age?
- Acute
- Subacute
- Chronic
What are typical clinical features of a subdural haemorrhage?
- Altered mental status
- Focal neurological deficits
- Headache
- Seizures
- Nausea and vomiting
- Drowsiness
- Signs of increased ICP
What is the first-line investigation for subdural haemorrhage?
CT scan
What are common clinical features of raised intracranial pressure?
- Headache
- Vomiting
- Reduced consciousness
- Papilloedema
- Cushing’s triad
What is Cushing’s triad?
- Widened pulse pressure
- Bradycardia
- Irregular breathing
What is a management strategy for raised intracranial pressure?
- Investigate and treat underlying cause
- Head elevation to 30 degrees
- IV mannitol
- Controlled hyperventilation
- Removal of CSF
