Subarachnoid Haemorrhage (SAH)**** Flashcards
Pathophysiology
Bleeding in the subarachnoid space, causing brain injury through local pressure, toxicity from bleeding and global raised ICP.
Rupture of berry aneurysms on the Circle of Willis
Presentation:
What type of headache do you get? Where?
What are sentinel headaches?
Symptom due to raised ICP
Symptom you get in epilepsy
Symptoms when it is quite severe
Thunderclap
Occipital
Milder headache in the preceding days to weeks, reflecting small aneurysmal leaks
Vomiting
Seizures
Collapse
Loss of consciousness
Coma
Signs:
They get signs of meningism - what are a few examples?
Kernig’s sign:
- What do you do?
- What is a positive sign?
Brudzinki’s sign:
- What do you do?
- What is a positive sign?
What other signs may you see?
Meningism - stiff neck, photophobia
Kenig’s sign:
- The patient lies supine.
- The hip and knee is flexed by the examiner up to 90 degrees..
- The examiner then attempts to passively straighten the leg at the knee.
- In a patient with a positive Kernig’s sign, the patient experiences pain along the spinal cord and the pain limits passive extension of the knee.
Brudzinki’s sign
- The patient lies supine in extension.
- The examiner gently grasps the patients head in the occipital lobe region and attempts flexion of the neck.
- Brudzinski’s sign occurs when flexion of the neck causes involuntary flexion of the knee and hip (an attempt by the patient to lessen the stretching of the inflamed meninges).
EXTRA INFORMATION:
Kernig’s Sign
- Occurs when the patient does not a the examiner to extend the knee of the elevated leg due to pain along the spinal cord.
- Bilateral Kernig’s sign is more likely to implicate meningitis.
Brudzinki’s Sign
- Neck stiffness upon test movement causes the involuntary flexion of the knee & hip.
- The patient experiences pain along the cervical spine and thoracic spine.
Paraesthesiae may also be experienced in the hands and feet FOR BOTH.
Retinal and sub hyoid haemorrhage
Focal neurological signs
Risk factors
Smoking HTN FH Hypercholesterolaemia Kidney disease - HTN control Coagulopathy
Investigations:
Why do you do:
- FBC
- Clotting
- What might happens to sodium levels and why?
- Glucose
- ECG
Anaemia
Coagulopathy
Low sodium due to cerebral salt wasting
May be elevated
SAH can cause cardiac abnormalities (e.g. long QT syndrome)
How is it diagnosed?
When is it most sensitive?
Non-contrast CT head
First 6 hrs
Lumbar puncture:
When is it done?
Why is it done?
What might you see in the CSF?
12 hrs after if CT negative
Yellowing due to Hb breakdown
4th bottle as they may be a new something
How is it diagnosed?
When is it most sensitive?
Non-contrast CT head
First 6 hrs
Lumbar puncture:
When is it done?
Why is it done?
What might be in the CSF? - starts with x
What machine is used to detect any Hb breakdown?
Why is on the 4th bottle used for the above?
What do you do to compare LP?
12 hrs after if CT negative
Yellowing due to Hb breakdown - Xanthochromia
Spectrophotometry
4th bottle as they may be RBC’s in the first few ones from a traumatic tap
Venous bloods - BR, protein and glucose comparison
Is CT or LP positive, how could the diagnosis be diagnosed?
CT angiogram
Management:
Where?
What regular neurological obs need to be done?
What SBP are you aiming for?
What can be given to reduce vasospasm?
What can be given for headache?
ITU
GCS
Pupils
Neurological signs
<180
Nimodipine - calcium channel blocker that reduces vasospasm
Analgesia
Management:
They should be referred to neurosurgery. What are the 2 things that can be done for them?
Clipping
Endovascular coil embolisation
Complications:
Acute:
Obstructive hydrocephalus
Rebleed
Vasospasm in the circle of willis (nimodipine given to prevent)
Arrhythmias
Pulmonary oedema
