Raised Intracranial pressure Flashcards
What causes a raised intracranial pressure?
Any additional volume within the skull
What can increase the volume within the skull?
Haematoma
Tumour
Excessive CSF
What is the normal ICP in adults in a supine position?
Normal ICP is 7-15 mmHg
What is the cerebral perfusion pressure?
Net pressure gradient causing cerebral blood flow to the brain
How is the cerebral perfusion pressure calculated?
CPP = mean arterial pressure - ICP
What are the main causes of raised intracranial pressure?
idiopathic intracranial hypertension
traumatic head injuries
infection- meningitis
tumours
hydrocephalus
What infection can cause a raised intracranial pressure?
Meningitis
What are the main features of raised intracranial pressure?
headache
vomiting
reduced levels of consciousness
papilloedema
Cushing’s triad
What is cushing’s triad?
widening pulse pressure
bradycardia
irregular breathing
What is the main investigation for raised intracranial pressure?
Neuroimaging- CT/MRI
Identify underlying cause
What other investigation/monitoring can be done for raised ICP?
Invasive ICP monitoring
What does invasive ICP monitoring involve?
Catheter placed into the lateral ventricles of the brain to monitor the pressure
What is the management of raised ICP?
Investigate and treat underlying cause
head elevation to 30º
IV mannitol
controlled hyperventilation
Removal of CSF
What is the function of IV mannitol?
osmotic diuretic
What is the function of controlled hyperventillation?
reduce pCO2 → vasoconstriction of the cerebral arteries → reduced ICP
