Neuro: haemorrhage Flashcards
What is the most useful imaging to diagnose a subarachnoid haemorrhage?
A CT without contrast is very useful here as it detects around 90% of SAH within 48-hours of onset.
Where does the bleeding occur in a SAH?
Subarachnoid haemorrhage involves bleeding in to the subarachnoid space, where the cerebrospinal fluid is located, between the pia mater and the arachnoid membrane.
Most common aetiology of SAH?
Ruptured cerebal aneyruysm
How does an SAH present?
THUNDERCLAP HEADACHE - sudden onset severe occipital headache, tyoically occuring during streneous activity, associated with vommiting and rapid drop in GCS
Neck stiffness
Photophobia
Vision changes
Neurological symptoms such as speech changes, weakness, seizures and loss of consciousness
SAH risk factors?
Hypertension
Smoking
Excessive alcohol consumption
Cocaine use
Family history
Subarachnoid haemorrhage is more common in:
Black patients
Female patients
Age 45-70
It is particularly associated with:
Cocaine use
Sickle cell anaemia
Connective tissue disorders (such as Marfan syndrome or Ehlers-Danlos)
Neurofibromatosis
Autosomal dominant polycystic kidney disease
What may be seen on CT in an SAH?
Blood will cause hyperattenuation in the subarachnoid space.
Management of SAH?
Patients should be managed by a specialist neurosurgical unit. Patients with reduced consciousness may require intubation and ventilation. Supportive care as part of a multi-disciplinary team is important with good nursing, nutrition, physiotherapy and occupational therapy involved during the initial stages and recovery.
Surgical intervention may be used to treat aneurysms. The aim is to repair the vessel and prevent re-bleeding. This can done by coiling, which involves inserting a catheter into the arterial system (taking an “endovascular approach”), placing platinum coils into the aneurysm and sealing it off from the artery. An alternative is clipping, which involves cranial surgery and putting a clip on the aneurysm to seal it.
Nimodipine is a calcium channel blocker that is used to prevent vasospasm. Vasospasm is a common complication that can result in brain ischaemia following a subarachnoid haemorrhage.
Lumbar puncture or insertion of a shunt may be required to treat hydrocephalus.
Antiepileptic medications can be used to treat seizures.
How to investigate SAH if CT head is negative?
Lumbar puncture, looking for:
Raised red cell count (take multiple samples as if decreasing each sample may just be traumatic bleed from LP itself)
Xanthochromia (yellow CSF caused by bilirubin)
Potential complications of SAH?
Vasospasam
Delayed cerberal ischemia
Arrythmias
Acute or chronic hydrocephelus
Most common cause of SAH?
Trauma
Extradural haemorrhage
This is a haemorrhage between the skull and dura mater of the meninges.
Commonly caused by trauma to the pterion, with subsequent tearing of the middle meningeal artery,
patients present with acute severe headache, contralateral hemiplegia, and a rapid deterioration in GCS following a lucid period.
On CT, a biconvex hematoma is diagnostic.
This occurs as the haemorrhage stops expanding at the sutures of the skull, where the dura meets the skull, causing the haemorrhage to expand towards the brain.
Neurosurgical
intervention is usually needed.
What type of cranial haemorrhage might present with a lucid interval
Extradural haemorrhage
Extradural haemorrhage
Haematoma expansion limited by sutures of the skull so expands towards the brain giving characteristic biconvex hyper dense area
Subdural haemorrhage
This is a hemorrhage between the dura mater and arachnoid mater.
They may be acute, subacute, and chronic, but tend to present more gradually than extradural hemorrhages, with gradually increasingheadache and confusion.
They tend to occur in older patients.
Other risk factors include historic head trauma, alcoholism, and anticoagulation.
On CT, a crescent-shaped hematoma is diagnostic. This occurs as expansion of the haemorrhage is not limited by skull sutures, so follows the contour of the skull.
Neurosurgical intervention may be needed, if the haemorrhage is severe and symptomatic enough.
Acute subdural haemorrhage
Haemorrhage flows contour of skull as not limited by skull sutures