Subarachnoid Haemorrhage

Question 1

What are the presenting features of a subarachnoid haemorrhage?

Answer 1

Sudden onset (“thunderclap”), occipital, severe headache

Signs of meningism (due to blood in the subarachnoid space) i.e. headache, vomiting, neck stiffness, photophobia

Reducing level of consciousness

Development of Focal Neurology

Seizures

Cardiac Arrest

Question 2

What congenital conditions are associated with an increased risk of subarachnoid aneurysm development?

Answer 2

Autosomal Dominant Polycystic kidney Disease

Ehlers Danlos Type 4

Familial intracerebral aneurysm disease

Pseudoxanthoma elasticum

Marfan’s Syndrome

Hereditary haemorrhagic telangectasias

Arteriovenous Malformations

Question 3

What non congenital risk factors are there for subarachnoid haemorrhage

Answer 3

Hypertension (uncontrolled)
Cigarette Smoking
Cocaine Use
Excessive Alcohol Use
Trauma
Arteriosclerosis
Increased size of existing aneurysm

Question 4

What imaging modalities can be used in the diagnosis of Subarachnoid Haemorrhage

Answer 4

Non Contrast CT Brain (1st line investigation)
It is highly sensitive for detecting subarachnoid blood and will also diagnoses potential complications such as cerebral oedema and hydrocephalus

N.B. if a non contrast CT brain is negative but Subarachnoid haemorrhage is still strongly suspected a lumbar puncture can be performed looking for red blood cells, bilirubin and xanthochromia

CT angiogram (can identify the site of the aneurysm)

Digital subtraction Angiography
Can be used if CT angiogram is negative radio opaque structures are removed from the images to enhance the view of the blood vessels

MRI brain (rarely used)

Question 5

What are the upper and lower acceptable Systolic Blood Pressure Values in a patient presenting with a subarachnoid haemorrhage

Answer 5

Systolic BP < 160mmHg and >100mmHg
Or MAP > 80mmHg

Question 6

Describe the World Federation of Neurosurgeons’ scale for grading Subarachnoid haemorrhage

Answer 6

The World Federation of Neurosurgeons’ (WFNS) scale is commonly used as a means of communicating severity and predicting outcome after a subarachnoid haemorrhage.

Grade 1 = GCS 15
Grade 2 = GCS 13-14 without motor deficit
Grade 3 = GCS 13-14 with motor deficit
Grade 4 = GCS 7-12
Grade 5 = GCS <7

Question 7

What are the neurological complications following acute subarachnoid haemorrhage

Answer 7

Re-bleeding (resulting in further brain injury)

Delayed cerebral ischaemia / Vasospasm ( Routine nimodipine for 21 days following subarachnoid haemorrhage reduces these risks, systemic hypertension with euvolaemia can also be used to increase cerebral perfusion in patients with vasospasm AND a secured aneurysm)

Hydrocephalus

Seizures

Cerebral Oedema

Death According to Neurological Criteria

Question 8

What specific complications are associated with endovascular coiling following a subarachnoid haemorrhage?

Answer 8

Complications relating to vascular access (normally femoral or radial), including: haemorrhage, infection, pseudoaneurysm formation

Intracranial vessel injury

Aneurysmal Rupture

Cerebral Vascular Occlusion resulting in ischaemia due to: thrombus, embolus (dislodgement from the aneurysmal sac) vasospasm, misplaced catheter or coils

Failure to coil the aneurysm adequately

N.B. most aneurysms are now managed neuroradiologically instead of via neurosurgical clipping. As well as coiling (where metal coils are deployed within the aneurysmal sac to occlude it) stents can be used to seal the coiled aneurysm off from it’s parent artery or to divert blood flow from the sac, however the use of such a stent necessitates the use of long term anti platelet therapy