Headache

Question 1

What are the common causes of severe headache?

Answer 1

1. Migraine
2. Subarachnoid haemorrhage
3. Meningitis/encephalitis
4. Tension headache

SAH is a red flag condition that should be considered and not missed, although uncommon

Question 2

describe common investigations used to diagnose SAH and its causes

Answer 2

Ix:

• CT
• If CT is negative & high clinical suspicion, perform lumbar puncture (look for bloodstained CSF that does not “clear” on three consecutive collection tubes & xanthochromia; Yellow staining due to breakdown of haemoglobin which occurs 6-8 hours after the SAH)

Causes of SAH: 
•Ruptured cerebral aneurysm – 70%
•Ruptured arteriovenous malformation – 10%
•Undiscovered / unknown – 15%
•Rare causes – 5%
–Spinal arteriovenous malformation
–Arterial dissection
–Tumour
–Bleeding diathesis

Question 3

describe the principles of early management of SAH

Answer 3

•Monitor and treat the symptoms and complications of SAH
–Pain, nausea, vomiting
–Raised intracranial pressure and hydrocephalus

•Prevent re-bleeding
–Diagnose and manage the cause of SAH

Question 4

describe the physiological principles of intracranial pressure

Answer 4

The skull is a fixed volume with 3 intracranial contents of brain, CSF, blood. If any of these increase in amount or if there is a mass occupying lesion (e.g. tumour), the volume of the intracranial contents increases and hence the ICP also increases.

I.e. ICP is directly related to the volume of the intracranial contents (Monro-Kellie doctrine)

Question 5

list the causes of raised intracranial pressure and their treatment

Answer 5

–A space occupying lesion: Tumour, blood clot, abscess

–Increased volume of normal intracranial constituents
•Brain e.g. cerebral oedema
•CSF e.g. hydrocephalus (as for Mr Styles)
•Blood e.g. vasodilatation due to hypercapnia from hypoventilation

Question 6

Describe a common Px of SAH

Answer 6

•Headache: sudden onset, severe, not previously experienced. Sentinel headache
•Reduced conscious state
•From normal to minor confusion to coma: 30% present deeply comatose or with sudden death
•Due to immediate effects of SAH or evolving hydrocephalus
•Meningism: Due to blood in the subarachnoid space. Headache, neck stiffness, photophobia, fever, vomiting
•Focal neurological signs. May be due to:
–Intracerebral component to the bleeding: Frontal or temporal haematoma
–Local pressure effects of the aneurysm, Especially third nerve palsy
–Cerebral vasospasm: Delayed 2-7 days after presentation

Typical story coincidentally: in the morning, during a shower

Question 7

Compare tension headache with migraine

Answer 7

•Tension headache
–Very common, associated with stress
–Gradual onset, BILATERALl or all over

•Migraine
–More common in women, often family history
–Often a past history
–Gradual onset, UNILATERAL, NAUSEA
–Accompanying or preceding visual or sensory deficit

Question 8

List 6 headaches (not as common) but not to miss & briefly list their Px

Answer 8

•Subarachnoid haemorrhage
–Sudden onset, severe, warning headache, family history

•Meningitis / encephalitis
–Fever, neck stiffness

• Subdural haematoma - Elderly, alcoholics, anticoagulants
• Space occupying lesion - Morning headaches, seizures, neurological deficit

•Giant cell arteritis
-Unilateral, over 50, visual disturbance, jaw claudication

•Glaucoma - Unilateral with visual disturbance

Question 9

DDx of SAH

Answer 9

• Meningitis
• Intracerebral haematoma: Hypertensive or amyloid haematoma
• Migraine, cluster headache
• Other causes of sudden onset headache. e.g. Headache with orgasm, Reversible cerebral vasospasm

Question 10

What do you look for in lumbar puncture of a patient with suspected SAH?

Answer 10

• bloodstained CSF that does not “clear” on three consecutive collection tubes
• xanthochromia; Yellow staining due to breakdown of haemoglobin which occurs 6-8 hours after the SAH

Question 11

What is the risk of re-bleeding of cerebral aneurysm & how can you avoid it?

Answer 11

•Common
–50% of patients within 6 weeks of 1st SAH
–25% of patients within 2 weeks of 1st SAH

Avoid by:
•Normotension
•Avoid pain, straining, vomiting, agitation, coughing etc
•URGENT diagnosis and treatment of the aneurysm
–CT angiogram / formal catheter angiography
–Surgical clipping of the aneurysm neck or endovascular coiling (Platinum wire coils are placed in the aneurysm angiographically to induce thrombosis)

Question 12

What is normal intracranial pressure & what factors determine it?

Answer 12

•Normal 10-15 mmHg
•ICP is directly related to the volume of the intracranial contents (Monro-Kellie doctrine)
•Intracranial contents are
–Brain
–CSF
–Blood

Question 13

Symptoms of raised ICP

Answer 13

•Headache
•Nausea and vomiting
•Drowsiness, eventual coma
•Papilloedema
•Signs of transtentorial herniation:
-Unilateral dilated pupil (third nerve palsy)
-Contralateral hemiparesis (midbrain)
-Hypertension/bradycardia (Cushing response; Cushing's triad)
-Respiratory failure

Question 14

What are (4) signs of transtentorial herniation?

Answer 14

• Unilateral dilated pupil (third nerve palsy)
• Contralateral hemiparesis (midbrain)
• Hypertension/bradycardia (Cushing response)
• Respiratory failure

Question 15

How do you treat raised ICP?

Answer 15

•Elevation of head to encourage venous return
•Diuresis to reduce cerebral oedema / extracellular fluid
•Hyperventilate/avoid hypoventilation
–Intubate and ventilate if necessary
•Sedate / paralyse
•Remove mass
•Drain hydrocephalus
–e.g. an external ventricular drain insertion to drain CSF prior to coiling of the aneurysm