Week 22 - Raised intercranial pressure, sub arach haemmorhage, subdural haematoma, vasovagal, tension headache Flashcards
how does one test for raised intracranial pressure
imaging - a CT of the head or MRI can reveal signs of raised ICP,
what are the signs on imaging of raised ICP
enlarged ventricles
herniation
or mass effect from causes such as tumours, abscesses, haemoatomas
what can you used to measure the pressure of the CSF
a lumbar puncture
what do subarachnoid haemorrhages involve
bleeding into the subarachnoid space, where the CSF fluid is located, between the pia mater and the arachnoid membrane
what is subarachnoid haemorrhage usually a result of
ruptured cerebral aneurysm
subarachnoid haemorrhages are most common in who
aged 45-70
women
black ethnic origin
what are the general risk factors for subarachnoid haemorrhage
hypertension
smoking
excessive alcohol intake
what is subarachnoid haemorrhage particularly associated with
Family history
Cocaine use
Sickle cell anaemia
Connective tissue disorders (e.g., Marfan syndrome or Ehlers-Danlos syndrome)
Neurofibromatosis
Autosomal dominant polycystic kidney disease
what is the typical history of a subarachnoid haemorrhage
sudden-onset occipital headache during strenuous activity, such as heavy lifting or sex
what does the sudden and severe onset of activity lead to in subarachnoid haemorrhage
thunderclap headache description - may feel like being struck over the back of the head
what are other important features of subarachnoid haemorrhage presentation
Neck stiffness
Photophobia
Vomiting
Neurological symptoms (e.g., visual changes, dysphasia, focal weakness, seizures and reduced consciousness)
what is the first line investigation for subarachnoid haemorrhage
CT head
what will be seen on a CT head with a subarachnoid
blood will cause hyper-attenuation in the subarachnoid space. however, a normal CT does not exclude a subarachnoid haemorrhage
what is considered after a normal CT in the case of suspected Sub Arach
lumber puncture
NICE recommends waiting at least 12 hours after the symptoms start before performing a lumbar puncture, as it takes time for the bilirubin to accumulate in the CSF.
what will a CSF sample show in the case of a sub arach
raised RBC - a decreasing red cell count on successive bottles may be due to a traumatic procedure
Xanthochromia - a yellow colour to the CSF caused by bilirubin
what is used after confirming the diagnosis of a sub arach
CT angiogrpahy is used to locate the source of the bleeding
what may be used to treat aneurysms
surgical intervention - this aims to repair the vessel and prevent re-bleeding.
this can be done by endovascular coiling, which involves inserting a catheter into the arterial system, placing platinum coils in the aneurysm and sealing it off from the artery
what is used to prevent vasospasm - a common complication of sub arachs
nimodipine is a CCB used to prevent vasospasm
vasospasm resulting in brain ischaemia
what are the treatment options for hydrocephalus in sub arachs
Lumbar puncture
External ventricular drain (a drain inserted into the brain ventricles to drain CSF)
Ventriculoperitoneal (VP) shunt (a catheter connecting the ventricles with the peritoneal cavity)
what are the four types of intracranial haemorrhage
Extradural haemorrhage (bleeding between the skull and dura mater)
Subdural haemorrhage (bleeding between the dura mater and arachnoid mater)
Intracerebral haemorrhage (bleeding into brain tissue)
Subarachnoid haemorrhage (bleeding in the subarachnoid space)
what are the risk factors for intracranial bleeds
Head injuries
Hypertension
Aneurysms
Ischaemic strokes (progressing to bleeding)
Brain tumours
Thrombocytopenia (low platelets)
Bleeding disorders (e.g., haemophilia)
Anticoagulants (e.g., DOACs or warfarin)
what is the presentation of a intracranial bleed
Sudden-onset headache is a key feature. They can also present with:
Seizures
Vomiting
Reduced consciousness
Focal neurological symptoms (e.g., weakness)
what is the minimum score on GCS
3/15
where does an extradural haematoma occur
between the skull and dura mater
what is an extradural haemorrhage usually caused by
a rupture of the MMA in the temporoparietal region
what is an extradural haemorrhage associated with
a fracture of the temporal bone
what is seen on a CT scan in the case of an extradural haemorrhage
they have a bi-convex shape and are limited by the cranial sutures (they do not cross the sutures, which are the points where the skull bones join together)
where does a subdural haemorrhage occur between and what causes it
the dura mater and the arachnoid mater and is caused by a rupture of the bridging veins in the outermost meningeal layer
what is seen on a CT of a subdural haemorrhage
they have a cresent shape and are not limited by the cranial sutures
who do subdural haemorrhages occur mostly in
the elderly and alcoholic patients, who have more atrophy in their brains, making the vessels more prone to rupture
what does intracerebral haemorrhage involve
bleeding in the brain tissue
how does an intracerebral haemorrhage present
similarly to an ischaemic stroke with sudden onset focal neurological symptoms, such as limb or facial weakness, dysphasia or vision loss
how do intracerebral haemorrhages occur
occur spontaneously or secondary to ischaemic stroke, tumours or aneurysm rupyure
what does a subarachnoid haemorrhage involve
bleeding in the subarachnoid space where the CSF is located, between the pia mater and the arachnoid mater.
what is a subarachnoid haemorrhage usually the result of
a ruptured cerebral aneurysm
what is the typical history/presentation of a subarachnoid haemorrhage
sudden onset occipital headache during strenuous activity, such as heavy lifting or sex. the sudden and sever eonset leads to ‘thunderclap headache’
what is required immediately in the management of a potential brain bleed
CT head is required to establish a diagnosis
what does initial management for an intracranial bleed involve
Admission to a specialist stroke centre
Discuss with a specialist neurosurgical centre to consider surgical treatment
Consider intubation, ventilation and intensive care if they have reduced consciousness
Correct any clotting abnormality (e.g., platelet transfusions or vitamin K for warfarin)
Correct severe hypertension but avoid hypotension
what are the surgical options for treating an extradural or subdural haematoma
craniotomy (open surgery by removing a section of the skull)
burr holes (small holes drilled into the skull to drain the blood)
what percentage of all headaches do tension headaches account for
40% of all headaches
how long do tension headaches last for and how often are they
they typically last for several hours, and often recur daily
are symptoms of a tension headache uni or bi lateral
bilateral
how do patients describe a tension headache
tight band sensation, pressure behind the eyes,
can be across the whole top of the head, typically frontal with or without radiation to the occiput
do tension headaches wake patients from their sleep
do not wake patients from their sleep - typically onset is after waking, often worse during the middle of the day
are tension headaches sensitive to head movement and is there a feeling of needing to vomit
not sensitive to head movement
no feeling of need to vomit
generally no neurological signs
does alcohol make a tension headache better or worse
better
what are the causes of tension headaches
stress
noise
concentrated visual effort
fumes/smells
how is tension headache diagnosed
using the International Headache Society Criteria
what does the International Headache Society criteria state
At least x10 episodes of similar headache
Head duration 30 min – 7 days
At least two of:
Non-pulsating
Mild or moderate intensity
Bilateral
Not aggravated by routine activity
Must have both of:
No nausea or vomiting
No photophobia or phonophobia (or only one of these)
Not attributable to another disorder
in chronic tension headache, how often should one take analgesia
limit analgesia to 2-3 days per week
what is a vasovagal episode caused by
caused by a problem with the autonomic nervous system regulating blood flow to the brain.
what happens when the vagal nerve receives a strong stimulus, such as an emotional event, temperature or pain
it can stimulate the parasympathetic nervous system. Parasympathetic activation counteracts the sympathetic nervous system, which keeps the smooth muscles in blood vessels constricted. As the blood vessels delivering blood to the brain relax, the blood pressure in the cerebral circulation drops, leading to hypoperfusion of brain tissue. This causes the patient to lose consciousness and “faint”.
how do patients usually feel before a vasovagal episode
Hot or clammy
Sweaty
Heavy
Dizzy or lightheaded
Vision going blurry or dark
Headache
how would an outsider describe a patient who had a vasovagal episode
Suddenly losing consciousness and falling to the ground
Unconscious on the ground for a few seconds to a minute as blood returns to their brain
There may be some twitching, shaking or convulsion activity, which can be confused with a seizure
