Adrenal Crisis

Addison's Disease

Anterior pituitary - ACTH, GH, FSH, LH, TSH, PRL

Posterior pituitary- ADH, oxytocin

Presentation

History of recent physical stress like stress, major injury, myocardial infarction 

Nausea and vomiting, muscle pains, confusion, coma, fatigue
Low BP or postural hypotension, tachycardia

Risk if ≥5 mg prednisolone equivalent for more than 4 weeks

Investigations

Hypoglycaemia
Low sodium

High potassium 

A patient with hypothyroidism feels worse on thyroxine

T1 DM with unexplained hypoglycaemia

Hyperuraemia
Hypercalcaemia
Metabolic acidosis
Random 9am cortisol  or short synacthen test - helps differentiate between primary and secondary adrenal insufficiency. 

Raised thyroid stimulating hormone (TSH)

Pathophysiology

Primary - disease affecting the adrenal gland  Addison's 

  Autoimmune 

  Infective (including TB, HIV and fungal) 

  Iatrogenic

  Haemorrhage or infarction (Waterhouse- Friedrichsen- meningococcemia)

  Malignant infiltration (metastasis, lymphoma) 

  Non malignant infiltration (sarcoidosis, haemochromatosis, amyloidosis)

  Genetic 

Secondary/Tertiary adrenal insufficiency (twice as common as addisons)

Panhypopituitarism

Pituitary apoplexy – infarction or hemorrhage of tumor

Chronic steroid therapy (suppresses HPA axis)

Tumors, granulomas

Treatment

1L/hour to maintain their BP

Hydrocortisone 100 mg with subsequent doses of 100 to 200 mg over 24 hours divided into three or four doses.

Look for and treat trigger 

Adrenal crisis. Do a random cortisol. Give steroids! ↓Na less likely unless SIADH, ↑K+ unlikely. #foamedhttps://t.co/K6h3shBZRJ pic.twitter.com/tTcoPehG3N

— South London EM FOAM (@slemfoam) June 15, 2017

Sick Day Rules
Double hydrocortisone if fever > 37.5 C or for infection or sepsis requiring an antibiotic

For severe nausea (often with a headache), 20 mg of hydrocortisone orally and sip rehydration or electrolyte fluids (such as dioralyte)

On vomiting, they should use their emergency injection if they have one (eg 100 mg of hydrocortisone) immediately. Then they should call a doctor, saying ‘Addison’s emergency’

They should take 20 mg of hydrocortisone orally immediately after a major injury to avoid shock

If patients have persistent vomiting or diarrhoea that is likely to interfere with absorption of medication or fluid balance, you should admit them to hospital for intravenous hydrocortisone

Some authors recommend that the dose of hydrocortisone should be increased (by 5 mg to 10 mg) before strenuous exercise.

Pituitary Apoplexy

Acute haemorrhagic or non-haemorrhagic necrosis of the pituitary gland. An existing pituitary macroadenoma is usually present (60-90%) but it can occur with healthy glands in few isolated cases. It is also more likely with medical treatment of a prolactinoma, pregnancy (Sheehan) and cerebral angiography, trauma and sudden changes in ICP.  

As the gland suddenly enlarges it may cause compression of structures adjacent to the sella leading to: 

  sudden headache

  loss of visual acuity with a chiasmal field defect

  oculomotor palsies (CN III) 

  Decreased level of consciousness, hypopituitanism, Addisonian crisis and subarachnoid irritation. 

Investigation

CT -  routine CT is insensitive to the diagnosis unless frank intracranial haemorrhage is present. The pituitary mass may be evident and be hyperdense. Fluid debris levels may also be evident. Useful to do to exclude a sub-arachnoid. 

MRI - typically demonstrates a pituitary region mass. Confirms the diagnosis in over 90% of patients. A pituitary CT is indicated if MRI is contraindicated or not possible.

Endocrine evaluation with blood samples for random serum cortisol, TSH, free T4, prolactin, IGF1, LH, FSH, testosterone (men), oestradiol (women) for later analysis

Hyponatraemia in 40% of cases 

Treatment

Hydrocortisone 100 mg i.m. bolus followed by 50–100 mg six hourly by intramuscular injection or 100–200 mg as an intravenous bolus followed by 2–4 mg per hour by continuous i.v. infusion can be used

Neurosurgical intervention should be considered in patients with:

   Severely reduced visual acuity

   Severe and persistent visual field defects

   Deteriorating level of consciousness

References 
https://lifeinthefastlane.com/ccc/adrenal-insufficency/

https://wikem.org/wiki/Adrenal_crisis

http://www.emdocs.net/em3am-acute-adrenal-insufficiency/

https://lifeinthefastlane.com/pediatric-perplexity-012/

http://sinaiem.org/tag/adrenal-crisis/

https://radiopaedia.org/articles/adrenal-insufficiency-1

http://www.emdocs.net/core-em-adrenal-crisis/

https://emsimcases.com/2017/02/14/adrenal-crisis/

http://www.endocrineconnections.com/content/5/5/G12

https://emedicine.medscape.com/article/765753-overview

http://learning.bmj.com/learning/module-intro/-diagnose-manage-adults-addison%27s-disease.html?moduleId=10013263&searchTerm=%E2%80%9Cadrenal%E2%80%9D&page=1&locale=en_GB

https://radiopaedia.org/articles/pituitary-apoplexy

http://www.endocrineconnections.com/content/5/5/G12.full

https://link.springer.com/article/10.1007/BF02112028

http://www.bmj.com/content/342/bmj.d1270

Cerebral Venous Thrombosis

In a lot of places I work, headaches either go home for GP review, or get admitted as a ?SAH. And if they're a possible SAHs, they get a normal CT in six hours (maybe) and many go home without an LP. This really worries me, as there's loads of other serious causes of headache I don't think we exclude thoroughly. In the "old" days, a second doctor generally reviewed the ?SAH to do (or get the results of) a lumbar puncture. So one of the diagnoses we could be missing that worries me is a cerebral  venous thrombosis - this is dangerous to miss.


 Is there a difference between cerebral venous thrombosis and cavernous venous sinus thrombosis?
CVT and CVST have common underlying etiologies including thrombosis, and terms are occasionally used synonomously. CVST is specifically thrombosis in the cavernous sinus, normally with infection, so cerebral venous thrombosis is a safer term.

Pathology
If you can't remember your venous sinus anatomy, check out Andy's posts on emergency medicine ireland. I can not think of a better way to learn anatomy.
At a very basic level, what happens is you get a clot in one of the veins in the head, which causes problems. At its worst, this can cause death and coma. Middling effects present as a stroke, especially now anyone slightly lopsided seems to get a stroke call. At the "mild" end, a headache may be the only presenting symptom.

There are lots of theories about what is happening to cause these symptoms. It is thought that venous occlusion leads to the development of collateral veins, which combined with altered arachnoid absorption of CSF causes cerebral oedema - which can cause the headache. They can also cause cerebral venous infarction (in 50% of cases) and even haemorrhage.


Risk Factors
Excess Oestrogen: 
oral contraceptive pill: very common cause in female patients <50 years of age 2
pregnancy, IVF
puerperium - more common then than in the pregnancy

Clotty 
prothrombotic haematological conditions: 35% 2
e.g. prothrombin 20210 (factor II) mutation 7
infection: especially mastoid sinus (dural sinus occlusive disease - DSOD)
systemic illness
dehydration: e.g. gastroenteritis
sepsis
malignancy
connective tissue disorders

Local Factors
skull abnormalities/trauma
compressing mass: e.g. meningioma

steroids
idiopathic: ~12% - this is worrying. If you're going to get a rare disease, being in the rarest bit of rare is unlucky!

Presenting Features
Headache (70-90% of cases)
    There is no particular "type" of headache, but it is normally persistent. Onset may be sudden, like in sub-arachnoid, or gradual. Most patients present with symptoms that have evolved over days or weeks.
Headache is the most frequently (80–90%) occurring symptom in cerebral venous thrombosis and often the first symptom reported by patients. The International Classification of Headache Disorders describes the headache as having no specific characteristics[2] but one study found the headache was usually acute or subacute in onset, localised, continuous and moderate to severe.[23] Cases have been reported where headache is the only neurological symptom or sign but this is very rare.

"Stroke"
  Stroke without any typical risk factors, especially in young people may be due to CVT. Up to 75% of cases have focal deficit and headache.
Diplopia here (CN VI palsy) is a focal sign here, and should stimulate you to look for papiloedema...and really think hard about CVT.

Symptoms are not always classic, but they can be associated with the thrombus location.3,4
– Cortical vein thrombosis presents with motor and sensory deficits, as well as seizure.
– Sagittal sinus thrombosis may present with motor deficits, bilateral deficits, and seizures.
– Patients with thrombus in the lateral sinus may present with intracranial hypertension and headache alone.
– Thrombosis of the left transverse sinus can present as aphasia.
– Thrombosis of the deep venous sinus can cause behavioral symptoms due to lesions in the thalamus.

Cavernous sinus thrombosis is associated with ocular pain, chemosis, proptosis, and oculomotor palsies.3,4


 Seizures
 Seizures occur in 30- 50% of presentations, and they are often followed by a Todd's paresis. Superior sagittal sinus thrombosis (4%) can present with bilateral or alternating neurological deficits.

 Coma or encephalopathy
This isn't common, but you can get a rapidly progressive illness with deepening coma, headache, nausea and pyramidal signs, due to extensive involvement of the deep cerebral veins.
More often other clinical manifestations present at onset or develop during the course of the disease. These include papilloedema, focal deficits, altered consciousness, seizures and cranial nerve signs, in particular diplopia caused by sixth nerve palsy. Psychosis, in conjunction with focal neurological signs, has also been reported.[25] The development of symptoms may occur over hours, days or even weeks.

Examination Features
 Papilloedema
 Altered vision
 Neurological symptoms

Investigations
Examination of the cerebrospinal fluid (CSF) does not necessarily help in establishing the diagnosis as there are no pathognomonic features. Abnormalities are found in up to 84% of cases and include raised CSF pressure, increased protein content, the presence of red blood cells and pleocytosis.
D-dimers probably not useful

Radiology 
CT -             Often normal, but there may be subtle hyperdensity of the affected sinus or vein for the first 7 - 14 days. May have associated venous haemorrhage or infarction. Haemorrhagic infarcts may be multiple, in no particular location.

String Sign
Seen in 25% of patients with a cavernous sinus thrombosis. It looks like elongated hyperdense image relating to the brain parenchyma.

Dense Triangle
This can be seen in the first two weeks in up to 60% of patients. Fresh, coagulated blood causes a superior sagittal sinus opacification. The opposite of this is the empty delta sign, where contrast is administered highlighting an intraluminal filling deficit. It is not a specific sign.


Treatment
Anticoagulation - In the last Confidential Enquiries into Maternal Deaths in the United Kingdom report there were four deaths from CVT compared with eight in 2003–05.[22] The previous report expressed the hope that increasing application of thromboprophylaxis among at-risk women will reduce deaths from both pulmonary embolism and CVT but figures are as yet too small to draw a conclusion.[1]

General measures like proper headboard inclination, adequate oxygenation, and protection of airway due to risk of bronchoaspiration are recommended (although now this has been disproved in stroke, I wonder if its accurate).
Anti-convulsant treatment after even a single seizure is reasonable

Lumbar puncture not recommended by LITFL

Full References 
http://onlinelibrary.wiley.com/doi/10.1111/tog.12101/full
http://onlinelibrary.wiley.com/doi/10.1111/tog.12101/abstract
https://lifeinthefastlane.com/ccc/cerebral-venous-thrombosis/
http://pmj.bmj.com/content/76/891/12
http://www.emdocs.net/cerebral-venous-thrombosis-pearls-and-pitfalls/
http://emedicine.medscape.com/article/1162804-overview#a7
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3858762/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4517419/
http://emergencymedicineireland.com/2012/03/anatomy-for-emergency-medicine-8-cerebral-venous-sinuses/
https://radiopaedia.org/articles/cerebral-venous-thrombosis
https://emin5.com/2017/02/22/approach-to-headaches/
https://stmungos-ed.com/s/N8.pdf

Headache

Headache is a massive subject to try and cover. One website nicely splits them into three main groups - so I'll go over headache in each of these groups...

Common
    Migraine Headache
    Tension Headache
    Cluster Headache

Killers
    Meningitis/encephalitis
    SAH / sentinel bleed
    Intracranial Hemorrhage (ICH) (subdura/epidural)
    Acute obstructive hydrocephalus (and blocked shunts)
    Space occupying lesions
    CVA
    CO Poisoning
    Basilar artery dissection
    Preeclampsia
    Cerebral Venous Thrombosis (pregnancy/post-partum)
    Brain abscess

Maimers
    Temporal Arteritis (>50yrs & ESR)
    Idiopathic Intracranial Hypertension (pseudotumor cerebri)
    Acute glaucoma
    Acute sinusitis

References
http://www.doctors.net.uk/ecme/wfrmNewIntro.aspx?moduleid=1559
 http://www.doctors.net.uk/ecme/wfrmNewIntro.aspx?moduleid=1553
http://learning.bmj.com/learning/module-intro/tricyclic-antidepressants-headaches.html?moduleId=10017236&searchTerm=%E2%80%9Cheadache%E2%80%9D&page=1&locale=en_GB
http://jnnp.bmj.com/content/72/suppl_2/ii33.full
http://embasic.org/2011/08/27/headache/
http://wikem.org/wiki/Headache
http://emeddoc.org/?p=481
http://flippedemclassroom.wordpress.com/category/headache/
http://lifeinthefastlane.com/education/symptoms/headache/
http://secure.collemergencymed.ac.uk/code/document.asp?ID=5074
http://guidance.nice.org.uk/CG150
http://www.sign.ac.uk/guidelines/fulltext/107/

Misc. Headaches

Benign Inter-cranial Hypertension
This is caused by raised CSF pressure, often in middle aged, obese females. It is occasional associated with a VI nerve palsy. It can be caused by SLE, CRF, endocrine problems. Also known as pseusotumour cerebri.

Symptoms:
Frontal headache, worse on lying down or stooping, night waking.
Can exacerbate migraines.
Lethargy, tiredness. Get papiloedema.

Investigations:
Need CT and MRI.

Treatment
Acetazolamide can help. Steroids in first two weeks LP shunt.

Management
Need to monitor vision
Antimigraine treatment may help.

Trigeminal Neuralgia
Stabbing unilateral pain. Treat with carbamazepine and oral analgesia. Admit if pain severe.

Space-occupying Lesion
Consider if headache always on same side. Dull, aching and headaches made worse by lying down or straining.

Central venous thrombosis
Presents similarly to SAH. May be associated with sinus infections, pregnancy and the post-partum period. May be missed on CT, but a clue would be raised intracranial pressure at LP.

Thunderclap Headache
several other potential vascular causes of thunderclap headache, other than SAH and these include:
    cerebral venous thrombosis
    arterial dissection
    ischaemic or haemorrhagic stroke
    intracerebral, intraventricular, extradural or subdural haemorrhage
    vasculitides
    reversible cerebral vasoconstriction syndrome

Pituitary Apoplexy
Occurs in 5% of patients with a pituitary tumour, and for 80% of patients is the first presentation of the tumour. Sudden onset headache, vomiting, visual impairment and decreased consciousness. Think about if headache + eye signs.

Brain Abscess

Thinking about these headache causing diseases when it comes down to a patient with HIV/AIDS. #FOAMED #aceprecap13 pic.twitter.com/O6F6Xe20JV

— FOAMed NL (@FOAMedNL) November 22, 2013

Symptoms of raised intracranial pressure, seizures and focal neurological deficits are most common forms of presentation.  Eventually many abscesses rupture into ventricular system, which results in a sudden and dramatic worsening of the clinical presentation and often heralds a poor outcome.



Toxoplasma gondii is an intracellular parasite that infects birds and mammals. Its definitive host is the cat. Excretion of oocytes in its faecal content followed by human contaminated uncooked consumption can lead to human infection. In immunocompetent individuals, it primarily causes a subclinical or asymptomatic infection. In immunocompromised individuals (e.g. AIDS patients), toxoplasmosis is the most common cause of a brain abscess.

http://m.adc.bmj.com/content/78/1/89.full http://radiopaedia.org/articles/idiopathic-intracranial-hypertension-1
http://radiopaedia.org/cases/benign-intracranial-hypertension-3 
http://annals.org/article.aspx?articleid=
http://radiopaedia.org/articles/dural_venous_sinus_thrombosis
http://radiopaedia.org/articles/cerebral-venous-thrombosis

http://radiopaedia.org/articles/brain-abscess-1
http://radiopaedia.org/cases/brain-abscess-1
http://ermentor.com/2013/10/does-that-hiv-infected-patient-with-a-headache-really-require-that-ct-head/
http://www.atsjournals.org/doi/abs/10.1164/ajrccm-conference.2013.187.1_MeetingAbstracts.A2958
http://radiopaedia.org/articles/cerebral-toxoplasmosis-2
http://lifeinthefastlane.com/education/ccc/toxoplasmosis/

Blocked VP Shunts

Normal Patho-physiology
- CSF produced at 0.35 ml/min (20 ml/hour or 500 ml/24 hours)
- Recycled over three times each day
- Capacity of normal lateral and third ventricles is approximately 20 ml
- ICP rises if production of CSF exceeds absorption. CSF production falls as ICP increases.

Shunts
Most shunting systems drain according to the differential pressure gradient between the ventricle and the tip of the distal catheter. Most neurosurgeons use medium pressure valves, that will drain CSF continuously if the differential pressure is over about 10 mm Hg. The ventricular catheter of a shunt is normally inserted through a burr-hole in the right parieto-occipital region and the valve will sit usually behind the right ear. The distal catheter is tunnelled subcutaneously down to another incision in the abdomen where it is then placed into the peritoneal cavity. It is not usually helpful for non-neurosurgeons to palpate or flush the shunt valve, as their contours and characteristics are so variable as to make interpretation notoriously inaccurate.

Blocked shunts:
blood or debris in the proximal site (choroid plexus within the ventricle can get stuck in it
fracture of the tubing along its course
infection of the tubing along its course
something like a piece of omentum getting stuck in the distal port in the abdomen

Hydrocephalus features
Young adults:
- Symptoms—headache, vomiting, failing vision, drowsiness, “muzziness of the head”, fatigue
- Signs—papilloedema, enlarged blind spots on visual field analysis or reduced visual acuity, failure of upward gaze, general clumsiness, dyspraxic gait, large head

Older adults/elderly:
- Symptoms—slowing of mental capacity, unsteady on feet/frequent falls, incontinence, drowsiness, headaches less frequently
- Signs—gait dyspraxia (slow, hesitant shuffling gait), dementia (reduced mini-mental score), rarely papilloedema

Clinical features of shunt malfunction:
Drowsiness and general malaise
Headaches
Vomiting
Papilloedema with or without failing vision
Occasionally failure of upward gaze
Neck stiffness
Thoracic back pain in patients with spina bifida
Abdominal tenderness or distension

Investigations
CT scan has sensitivity of 80% and shunt series (plain films of neck and abdo) has sens of 20% but you still need both.
Head CT (to help define if there is hydrocephalus vs overdrainage)
Shunt Series (to image the apparatus for obvious kinks and breaks)Peripheral blood for C reactive protein, white cell count if there has been any recent surgery
ICP monitoring/lumbar infusion test

http://jnnp.bmj.com/content/73/suppl_1/i17.full
http://adc.bmj.com/content/87/3/198
http://emergencymedicineireland.com/2012/04/raised-icp-and-intracranial-shunts-some-notes/
http://pedemmorsels.com/tapping-a-vp-shunt/

Glaucoma

Glaucoma is listed in the headache syllabus, but no-where else. It's implied in the red eye syllabus.

Epidemiology
- Affects 2% of over 40 years old
 - Up to 10% of those above 80 years.
 - Second most common cause of blindness in the UK 
- Accounts for 10% of registrable blindness.

Pathopysiology
There are two types of glaucoma - open or closed. The "angle" in open-angle glaucoma refers to the angle between the iris and the cornea.

Closed-angle glaucoma occurs when the iridocorneal angle narrows so much that the aqueous fluid is unable to flow from the posterior to the anterior chamber and cannot reach the trabecular meshwork.

Open-angle glaucoma tends to progress at a slower rate than closed-angle glaucoma, and patients may not realise they have vision loss until there has been irreversible damage to the optic nerve and retinal nerve fibres. Acutely, closed-angle glaucoma is much more important to know about.

Risk factors include:
- history of previous episodes recent use of anticholinergic drugs
- African or Afro-Carribean origin Chinese, Hispanic and Inuit origin
- ocular hypertension (OHT)
- increasing age
- short sightedness (myopia)
- family history
- diabetes

Symptoms
- acute onset of a red and painful eye
- impaired vision
- multicoloured haloes (like a rainbow) forming around lights
- nausea, vomiting and headache

The acute attack can be preciptated by:
- topical mydriatics anticholinergic and sympathomimetic drugs
- emotional stimuli
- accommodation (e.g. reading)
- dim light 

Treatment
There are five main drug classes of glaucoma eye drops:
- prostaglandin derivatives beta-blockers carbonic anhydrase inhibitors
- sympathomimetics miotics
- head up at least 30 degrees
- symptomatic treatment of pain and nausea/ vomiting
- discontinue any precipitants and treat underlying causes

It is controversial whether to start treatment in the ED or not. I suspect it depends on transfer time to ophthalmology assessment. Consider opiate analgesia, an antiemetic and acetazolamide 500mg IV then 500mg PO. Treatment with a topical miotic such as pilocarpine 1 or 2% every 5 minutes should be started approximately 1 hour after commencing other measures as initially the pupil is usually paralysed and unresponsive.

References 
http://www.enlightenme.org/knowledge-bank/cempaedia/atraumatic-red-eye
http://www.enlightenme.org/learning-zone/under-pressure 
http://www.enlightenme.org/knowledge-bank/cempaedia/eye-initial-assessment
http://www.ophthobook.com/chapters/glaucoma 
http://learning.bmj.com/learning/module-intro/glaucoma-chronic-open-angle-glaucoma-ocular-hypertension-diagnosis-management-.html?moduleId=10013290&searchTerm=%E2%80%9Cglaucoma%E2%80%9D&page=1&locale=en_GB
http://www.doctors.net.uk/ecme/wfrmNewIntro.aspx?moduleid=1350
http://lifeinthefastlane.com/ophthalmology-befuddler-007-2/

Subarachnoid Haemorrhage

SAH - the most feared cause of headache. Syncope + headache = think SAH.

Anatomy 
Most SAHs occur in the circle of Willis - as this is where the brain gets its blood supply from.

There are two types of aneurysm with slightly different pathophysiology behind them. 

Saccular Aneurysms: Approximately 90%, with high morbidity and mortality. The internal elastic membrane weakens, at the site of vessel bifurcation where blood flow is most turbulent.

Fusiform Aneurysms: These develop from ectatic, tortuous cerebral arteries, most often in the vertebrobasilar system. Patients with fusiform aneurysms characteristically present with symptoms of cranial-nerve or brainstem compression, but the symptoms are not commonly associated with subarachnoid hemorrhage.

Epidemiology

Screening is not beneficial, even in those with first degree relative history. If screening is appropriate, cranial MRA is used. 

Aneursyms:

    NOT Congenital - increased risk if first degree relative has SAH

        With 2 relatives, 10 year risk of 7.1% versus 0.8%
    Occur in about 1 in 40 people (1-5%).
    Most never rupture.
    Multiple aneurysms in 30%.  

    Berry aneuryms have increased rate of formation in:
       Autosomal dominant polycystic kidney disease
       Pseudoxanthoma elasticum
       Ehler-Danlos syndrome type IV.

SAH:
     1-7% of all strokes.
     More common in young men than young women
     Overall, more common in women. 
     Aspirin increases the mortality if it bleeds

     Oestrogen deficiency (post - menopausal) raises the risk. 

     Hypertension

     Smoking

     Sympathomimetic drugs (phenylephrine and cocaine)

Diagnosis

Missed in 1/4 of patients as characteristic headache not present. 

50% of patients rebleed within six months of the presentation

After that, 3% per year thereafter

Even in these patients, the possibility of having an intracranial aneurysm is low and screening all patients is not required in the absence of a positive family history. Cranial MRA is the imaging method of choice for screening.

Clinical Presentation - the Headache

Classically Instantaneous:
    Instantaneous – 50%
    2-60 seconds – 24%
    1-5 minutes – 19%
    No idea/unable to remember – 9%
1 hour has been suggested. The typical duration is of the order of 1-2 weeks.

Features 

Pancephalic

Lateralised in one third of patients

Sentinel Bleed:
  No medical attention sout, or one missed. 

  Present in 30 - 50%

The classic headache, caused by aneurysmal rupture, release of blood, and raised ICP, happens in 97% of patients. Only around 25% of patients who visit A&E with this sudden severe headache (so called, “the worst headache of my life”) have acute subarachnoid haemorrhage. In only 12% of them, headache is the only complaint.

Clinical Features - other

Vomiting is not predictive but present in 75% 

Seizure at onset (74%)

Reduced level of consciousness in 2/3 of people

Transient loss of consciousness in 26%
Delirium (1%)

Focal neurology (15%)
3rd nerve palsy due to an aneurysm in the posterior communicating artery.
1 in 7 will have intraocular haemorrhages.
Ischaemic changes (of any type) on ECGare common

Neck stiffness may develop – but usually only after several hours and is due to an inflammatory reaction to the blood in the subarachnoid space, and it may not develop at all if there’s only a small amount of blood.

Imaging

    CXR: neurogenic pulmonary oedema
    CTH: 90% sensitive within 24 hrs, 50% @ 72 hrs, detects hydrocephalus
    CTA: assesses vascular anatomy
    DSA: gold standard for diagnosis, allows intervention
    MRI: mostly used for detection of AVM

CT:
    98% sensitivity if scanned within 12 hours of onset.
    93% within 24 hours.
    50% at 5 days – based on study from 1984.
Sensitivities unlikely to improve because small bleeds will be flushed away by normal CSF flow.   There may not be enough blood present to appear as hyperdense to CSF on scanning.

Angiography:

Cerebral angiography within 48-72 hours of the initial event.

Lumbar Puncture
1 in 10 of patients presenting with thunderclap headaches will have had a subarachnoid haemorrhage.
A non-contrast CT within 12 hours of onset of pain is 98% sensitive for detecting SAH.
Therefore the risk of missing a SAH may be as low as 2 in 1000 if the patient has had a negative CT in this timeframe.
Xanthochromia A fancy way of saying ‘Yellow colour’! - Bilirubin
    96% sensitive if done 12 hours post headache
    Positive for at least 2 weeks (possibly up to 4 weeks)  

Other Investigations
ECG: tall peaked T waves, ST depression, prolonged QT, arrhythmia
Echo: neurogenic cardiomyopathy
Hyponatraemia + hypovolaemia from SAIDH or cerebral salt wasting -> worsens vasopasm
Troponin rise due to cardiomyopathy
Magnesium - may be low, poor prognosis.
 
Treatment
Supportive care as appropriate
Neurosurgery - surgical clipping or coil
Treat seizures (occur in 18% of patients) with benzodizepines and load with phenytoin 18 mg/kg IV
Prevent vasospasm - Nimodipine
   (calcium channel antagonist with some selectivity for cerebral circulation)
Lower the SBP to below 140 mm Hg to help reduce the risk of rebleeding using intravenous labetalol. Avoid
   vasodilators, such as nitroglycerin and sodium nitroprusside, because they increase the intracranial blood    volume and intracranial pressure
If your patient is unconscious, you should not try to lower their blood pressure, at least temporarily

Anti-fibrinolytics, e.g. tranexamic acid
— controversial
— may reduce risk of re-bleed but increase risk of VTE
— some centers give until aneurysm is secured if no VTE risk factors, monitor for DVT

Treat fever - occurs in 70% of SAH and requires aggressive control. Look for and treat infection. Antipyretics.

3% will have a cardiac arrest. Aggressive resuscitation is essential as they appear to have a high rate of ROSC and half of the survivors will regain independent living.

Prognosis
Rebleeding - 24 to six hours
Vasospasm - 3 days to 2 weeks 

Death - within three weeks after subarachnoid haemorrhage. 40 - 50% of patients die.

Dependent - in a third of survivors

Hunt and Hess grading
    Grade 0: Unruptured aneurysm without symptoms.
    Grade 1: Asymptomatic or minimal headache and slight nuchal rigidity (1% mortality).
    Grade 1a: No acute meningeal or brain reaction, but with fixed neurological deficit.
    Grade 2: Moderate-to-severe headache, nuchal rigidity, no neurological deficit other than cranial nerve palsy (5% mortality).
    Grade 3: Drowsy, confused or mild focal deficit (19% mortality).
    Grade 4: Stupor, moderate-to-severe hemiparesis, possible early decerebrate rigidity and vegetative disturbances (42% mortality).
    Grade 5: Deep coma, decerebrate rigidity, moribund appearance (77% mortality).
    If there is a co-existing serious illness, this adds a grade.

The Ottawa Sub-Arachoid Rule

For alert patients older than 15 y with new severe nontraumatic headache reaching maximum intensity
within 1 h. Not for patients with new neurologic deficits, previous aneurysms, SAH, brain tumors, or history of recurrent headaches (=3 episodes over the course of =6 mo)
    Investigate if 1 or more high-risk variables present:
-   Age =40 y
-    Neck pain or stiffness
-    Witnessed loss of consciousness
-    Onset during exertion
-    Thunderclap headache (instantly peaking pain)
-    Limited neck flexion on examination

References

http://www.enlightenme.org/learning-zone/grading-subarachnoid-haemorrhage
http://www.aafp.org/afp/2002/0815/p601.html
http://learning.bmj.com/learning/module-intro/subarachnoid-haemorrhage-diagnosis-management.html?moduleId=10022933&searchTerm=%E2%80%9Csubarachnoid%E2%80%9D&page=1&locale=en_GB
http://www.bmj.com/content/341/bmj.c5204?sso= 

http://www.bmj.com/content/339/bmj.b2874?sso=

http://lifeinthefastlane.com/subarachnoid-haemorrhage/
http://radiopaedia.org/articles/subarachnoid-haemorrhage 

http://lifeinthefastlane.com/education/ccc/subarachnoid-haemorrhage-grading-systems/ 

http://lifeinthefastlane.com/education/ccc/subarachnoid-haemorrhage/ 

http://lifeinthefastlane.com/education/ccc/vasospasm-in-subarachnoid-haemorrhage/ 

http://lifeinthefastlane.com/education/ccc/coiling-versus-clipping-in-subarachnoid-haemorrhage/

http://lifeinthefastlane.com/education/ccc/subarachnoid-haemorrhage-icu-management/ 

http://lifeinthefastlane.com/education/ccc/subarachnoid-haemorrhage-initial-management/ 

http://academiclifeinem.com/journal-club-clinical-decision-rule-subarachnoid-hemorrhage/ 

http://jama.jamanetwork.com/article.aspx?articleid=1741823 

http://lifeinthefastlane.com/education/ccc/subarachnoid-haemorrhage-prognostication/ 

http://emcrit.org/podcasts/sah/ 

http://www.smartem.org/podcasts/subarachnoid-hemorrhage-rational-approach 

http://resus.me/cardiac-arrest-caused-by-subarachnoid-haemorrhage/ 

http://www.ahcmedia.com/emreports/pearls/pearls39.html 

http://jnnp.bmj.com/content/65/5/791.full

Temporal Arteritis

Temporal arteritis is a rare cause of a headache but one that I always worry about missing. I remember as an FY2 in GP land, my tutor running through an examination on how to exclude serious causes of a headache. She palpated the temporal arteries - and now, I always do too!

AnatomyThinking about the anatomy of the carotid arteries is a good start to understanding the pathophysiology of temporal arteritis. For some reason, although any artery could be affected, the carotid arteries are much more frequently affected.





The superficial temporal artery is a branch of the external carotid artery. To test yourself on anatomy, I'd recommend the lumen website.  If you look at the anatomical pictures, the vessel I used to think about as the temporal artery is not - and the temporal artery is a lot higher and more posterior than I realise.
To remember the branches:
"Some Anatomists Like Fornication, Others Prefer S & M"
S - Superior Thyroid Artery
A - Ascending Pharyngeal Artery
L - Lingual Artery
F - Facial Artery
O - Occipital Artery
P - Posterior Auricular Artery
S - Superficial Temporal Artery
M - Maxillary Artery


PathophysiologyOnce again, the Calgary Guide summarises everything you need to know. It is important to remember that the acute phase reaction can cause both a fever, and raised inflammatory markers so a careful history and examination is needed - you're unlikely to be treating meningitis!

Histology shows intimal proliferation with giant cells, evidence of elastic lamina damage and periarterial lymphocytic infiltration. Because temporal arteritis causes skip lesions, biopsies need to be taken at more than one place.

About 50% of patients with giant cell arteritis also have polymyalgia rheumatica and 15% to 20% of patients with polymyalgia rheumatica have evidence of giant cell arteritis on biopsy

Clinical Presentation
Again, the Calgary Guide covers everything! Headache and scalp tenderness is the presenting symptom most people comment on, but don't forget jaw claudication and stroke or TIA like symptoms.

The American College of Rheumatology has criteria for diagnosing giant cell arteritis. These were written a long time ago in 1990, and as far as I can tell, haven't been updated! Diagnosis can be made if the patient has at least three of these criteria. This gives a sensitivity of 93.5% and a specificity of 91.2%.

1. Age at disease onset >=50 years
2. New headache
3. Temporal artery abnormality
  Temporal artery tenderness to palpation or decreased pulsation, unrelated to arteriosclerosis of cervical arteries. I'm not sure how you prove it's unrelated to arteriosclerosis!
4. Elevated erythrocyte sedimentation rate
Erythrocyte sedimentation rate >=50 mm/hour. This happens in 95% of patients. CRP is often used instead, and one study suggests it is a more sensitive marker than ESR.
5. Abnormal artery biopsy.
The temporal artery biopsy may be normal in 42% to 61% of the patients.

Imaging
A normal colour duplex ultrasound of the temporal artery makes giant cell arteritis unlikely with a negative predictive value of greater than 95%.

Treatment
- Prednisolone 40 mg daily
(If sight affected 60mg if  just pmr 15mg)
- Temporal artery biopsy within two weeks.
- Reduce the dose after one to two months of treatment.
- 30% to 50% of patients can stop taking steroids after two years
- Remember bone protection. Bisphosphonates, calcium and vitamin d.
- PPI if on NSAID too - not if just on prednisolone.
- Rheumatology referral, especially if frequent relapses and patients are unable to reduce their dose of prednisolone to an acceptable level.

Prognosis
The symptoms of GCA should improve in one to two weeks. Symptoms of polymyalgia improve in 48 to 72 hours.

MT “@JAMA_current: #Headache, pain chewing, & tenderness💡 #TemporalArteritis ⬆️ http://t.co/Lw352M0NVx #RatlClinExam pic.twitter.com/P5FXudvP9H”

— Ixekizumab (@Brodalumab) April 20, 2014

5-10% of central retinal artery occlusions are associated with temporal aka giant cell arteritis #themoyouknow #usmle

— JGu (@absolutjag9) April 19, 2014

#Headache, jaw claudication, & scalp tenderness? #TemporalArteritis more likely http://t.co/vv9IB4WVE3 #RatlClinExam pic.twitter.com/rZfIjfVAD5

— JAMA (@JAMA_current) April 19, 2014

Other Similar Diseases
Takayasu's arteritis affects young women and causes:
    Absent pulses in the arms
    Neck bruits
    Transient ischaemic attacks
    Visual symptoms.

Polyarteritis nodosa causes:
    Muscle pains
    "Abdominal angina"
    Livedo reticularis
    Anaemia
    Leucocytosis
    Proteinuria
    Raised ESR.

Polymyositis is most common in middle-aged women. It causes:
    Pain and weakness in proximal muscles
    A very elevated creatinine kinase.
Many patients with polymyositis have antinuclear antibodies.

References
http://learning.bmj.com/learning/module-intro/giant-cell-arteritis-diagnosis-treatment.html?moduleId=5001096&searchTerm=%E2%80%9Ctemporal%20arteritis%E2%80%9D&page=1&locale=en_GB
http://www.ncbi.nlm.nih.gov/pubmed/22119103
http://learning.bmj.com/learning/module-intro/.html?moduleId=10037282&searchTerm=%E2%80%9Ctemporal%20arteritis%E2%80%9D&page=1&locale=en_GB
http://bestbets.org/bets/bet.php?id=708http://ard.bmj.com/content/58/6/335.full
http://www.rheumatology.org/ACR/practice/clinical/classification/tcatree.asp
http://www.rheumatology.org/ACR/practice/clinical/classification/tca.asp
http://calgaryguide.ucalgary.ca/slide.aspx?slide=Giant%20Cell%20%28Temporal%29%20Arteritis%20-%20Pathogenesis%20and%20investigations.jpg
http://calgaryguide.ucalgary.ca/slide.aspx?slide=Giant%20Cell%20%28Temporal%29%20Arteritis%20-%20Clinical%20findings%20and%20Complications.jpg

Migraines

Pathophysiology

I think this picture from the amazing Calgary guide summarises everything very well.

Basically, something starts it off - we don't know why. Everything gets sensitised, and the patient has lots of pain. The pain fibres in the walls of intercerebral blood vessels are part of the trigemial nerve, which also supplies sensation to the face. This is why referred pain is common.

Epidemiology and Triggers
Migraine is three times more prevalent in women (about 18% of the population) than in men (about 6%).

Food includes MSG, tyramine - containing foods and nitrate containing foods (and skipped meals!)
Menstruation is a migraine trigger in 10% of women with migraine. This is often overestimated by the patient: true menstrual migraine can be diagnosed only after examining a few months of the headache and menstrual diary. The OCP may help, but the helpful effect is lost during the pill free week.

There is an increased risk of fatal ischaemic stroke in people with migraine with aura, increased in people using combined hormonal contraception.morrhagic stroke.

Clinical Features
To officially diagnose migraines, the following criteria must be met:
The headache should have two or more of the following characteristics:
    Unilateral location
    Pulsating quality
    Moderate to severe pain intensity
    Aggravated by or causing avoidance of routine physical activity.

The headache should be accompanied by one or more of:
    Nausea
    Vomiting
    Photophobia
    Phonophobia.
The headache should not be attributable to another disorder and there should be no red flags (abnormal neurology, systemic symptoms such as fevers, chills, and weight loss, rapid increase in headache frequency, orthostatic worsening of symptoms, exertional worsening of symptoms, new onset, thunderclap headaches (very severe headache that reaches maximum intensity in <1 min), with existing risk factors for a secondary headache (such as cancer or hypercoagulable state) or overuse of headache abortive drugs.
This is nicely summarised with this mneumonic:

When does a "normal headache" become a migraine? You can have migraine with or without aura. Most of my headaches could be officially diagnosed as migraine. I call them a migraine if I HAVE to go to bed, and a headache if I struggle on with pain killers. But officially... Officially migraine causes bed rest or severe impairment in more than half of people.

Other useful pointers to a diagnosis of migraine include:
    family history of headache/ migraine
    motion sickness or cyclical vomiting as a child
    delayed headache following alcohol, or "unfair" tendency to hangovers
    typical migraine triggers, for example sleep disturbance, missing meals, relaxation, pre- or perimenstrual timing, cheese, wine, chocolate, citrus, etc

Typical aura symptoms include visual, sensory and speech symptoms. Visual symptoms are most common, and include flickering lights, spots or lines, or loss of vision (blind spots or scotoma). An aura typically lasts for <60 minutes, and usually precedes or sometimes accompanies the headache. Around a third of migraine sufferers report the experience of aura symptoms. Only just over half of migraine sufferers who experience aura experience it with every attack. Most aura symptoms last between 30 minutes and one hour and occur before the onset of pain.

Chronic migraine is properly defined as >15 days of headache per month, with >eight days being migraine, for at least three months. The definition excludes people who overuse medication

Treatment
Consider rectal treatment if IV inappropriate or for home. Do NOT  use opiates!
Naproxen: NNT of 11.
Aspirin: 1000mg
Ibuprofen is more effective than paracetamol at pain relief for migraine attacks in children

Chlorpromazine: IV + NaCl
Prochlorperazine: 10mg IV + NaCl is better than metoclopramide
Metoclopramide: Conflicting evidence
Haloperidol: 2.5 mg of haloperidol as a substitute (the literature on this is scarce, and some of it is old).

Triptans: More effective if taken in the prodromal window. They block the stimulation of the trigeminal ganglion and preventing the sensation of pain. The triptans are selective 5-hydroxytryptamine (5HT) receptor agonists, with high affinity for the 5HT1B and 5HT1D receptors. 5HT1B receptors are on smooth muscle cells of blood vessels and cause vasoconstriction when stimulated.
Around 1-7% of participants in clinical trials (without cardiovascular disease) experience “triptan sensations”—a burning, tingling, or tightness in the face, neck, limbs, or chest—which is not associated with electrocardiographic or enzymatic evidence of myocardial ischaemia.
Triptans are not recommended for use in pregnancy or in the presence of coronary heart disease, as there are also receptors in the coronary arteries.

Propofol: 20-30mg every 3 - 5minutes reduces pain quickly and effectively. I don't think it'd ever be in my top million treatments!
Dexamethasone: 26% relative reduction in headache recurrence (number needed to treat=9) in 72 hours.

Prophylaxis
Pharmacological prophylaxis is recommended in those who:
-    Have frequent, high impact migraine attacks (>4 per month)
-    Are not treated satisfactorily with appropriate acute medications
-    Have concomitant conditions that do not allow the use of acute medications (for example, a migraine variant)
-    Are overusing acute medications, or have chronic primary headache, or both
-    Advice on behavioural and physical therapies, including acupuncture, relaxation, biofeedback, stress reduction, cervical manipulation, massage, exercise and avoiding migraine triggers. Change in sleeping times at weekends and irregular shift work may usefully be avoided, as is the abrupt let-down from stress.
-    Feverfew, magnesium, and vitamin B2

Propanolol, topiramate and acupuncture should be considered.

References:
http://jnnp.bmj.com/content/early/2012/07/23/jnnp-2012-302487
http://circ.ahajournals.org/content/118/14/1405.full
http://emupdates.com/2009/11/23/migraine-criteria-for-diagnosis/
http://socmob.org/2013/11/propofol-migraine-part-2/
http://bestbets.org/bets/bet.php?id=545
http://bestbets.org/bets/bet.php?id=88
http://bestbets.org/bets/bet.php?id=504http://bestbets.org/bets/bet.php?id=787
http://bestbets.org/bets/bet.php?id=1036http://bestbets.org/bets/bet.php?id=2454
http://bestbets.org/bets/bet.php?id=2333
http://bestbets.org/bets/bet.php?id=2045
http://bestbets.org/bets/bet.php?id=2074http://bestbets.org/bets/bet.php?id=2458
http://academiclifeinem.com/on-the-horizon-propofol-for-migraines/
http://annals.org/article.aspx?articleid=715803http://empharmd.blogspot.co.uk/2013/05/milking-it-propofol-for-migraine.html
http://jnnp.bmj.com/content/72/suppl_2/ii10.full
http://learning.bmj.com/learning/module-intro/preventive-%CE%B2-blocker-migraine-optimised-acute-migraine.html?moduleId=10017044&searchTerm=%E2%80%9Cmigraine%E2%80%9D&page=1&locale=en_GB
http://www.bmj.com/content/348/bmj.g1416.pdf%2Bhtml
http://www.bmj.com/content/347/bmj.f6952.pdf%2Bhtml
http://bestbets.org/bets/bet.php?id=1416
http://www.enlightenme.org/node/2331
http://learning.bmj.com/learning/module-intro/migraine-diagnosis-prevention.html?moduleId=5003207&searchTerm=%E2%80%9Cmigraine%E2%80%9D&page=1&locale=en_GB
http://learning.bmj.com/learning/module-intro/migraine-patient-experience-pathology-therapies.html?moduleId=10021852&searchTerm=%E2%80%9Cmigraine%E2%80%9D&page=1&locale=en_GB
http://learning.bmj.com/learning/module-intro/migraine-haemorrhagic-stroke-women.html?moduleId=10016760&searchTerm=%E2%80%9Cmigraine%E2%80%9D&page=1&locale=en_GB
http://calgaryguide.ucalgary.ca/slide.aspx?slide=Migraines%20and%20Auras%20Pathogenesis%20and%20Clinical%20Findings.jpg

Tension Headache

Re @embasic The proper dose of opioids for acute headache is 0.0 mg/kg #foamed
— Mike Abernethy (@FLTDOC1) April 3, 2014

Tension Headache and Medication Overuse headache are very similar in my head (the former sometimes literally), so I'm going to cover both of them together!

Tension Headache
Tension headache can be episodic or chronic. It is normally described as a featureless headache. It can cause daily or very frequent headaches, lasting minutes to days.
- Symptoms begin before the age of 10 years in 15% of people with chronic tension-type headache.
- It affects 4.1% of the population
- 65% of cases are women
It is thought to be triggered at least partially by stress.

The 2004 International Headache Society criteria for chronic tension-type headache are:
- Headaches on 15 or more days a month (180 days/year) for at least three months
- Pain that is bilateral, pressing, or tightening in quality and non-pulsating, of mild or moderate intensity, which does not worsen with routine physical activity such as walking or climbing stairs
- Presence of no more than one additional clinical feature (mild nausea, photophobia, or phonophobia) and without moderate/severe nausea or vomiting.
- Causes of normal headache --> chronic daily headache:

Interesting review of tension headache therapeutics in ED http://t.co/74XEv6lqMG #FOAMed #FOAM4GP
— Casey Parker (@broomedocs) March 15, 2014

Treatment
- Prevention is better than cure
- Amitriptyline or mirtazapine are both helpful
- CBT

Medication Overuse Headache
Medication overuse headache is difficult to diagnose, as the type of headache that develops varies eg patients with underlying migraine report migraine-like daily headache.
It is caused by tolerance, and withdrawal.
They normally use large quantities of medication (eg 35 doses/ week; six different drugs). Opiods and barbiturates are more likely to cause it.
It is the frequence rather than the absolute quantity that is important. Caffeine is thought to make you more susceptible.
- Prevalence around 1% of adults and 0.5% of adolescents (aged 13–18 years)
- Most prevalent in those aged around 40–50 years and affects about three times more women than men.

Symptoms improve 1- 6 months after withdrawal of medication. Simply recognising medication overuse and advising patients about its bad effects can be enough to significantly reduce the problem- in one study after identification of the problem, 76% no longer overused medication, and 42% no longer had chronic headache. The rate of relapse is high (between one-third and one-half of patients in specialist headache clinics), being more likely with opiates and simple analgesics than triptans.

References
http://dtb.bmj.com/content/48/1/2.abstract
http://learning.bmj.com/learning/module-intro/chronic-tension-headache.html?moduleId=10007571&searchTerm=%E2%80%9Ctension%E2%80%9D&page=1&locale=en_GB
http://bestpractice.bmj.com/best-practice/monograph/12.html
http://www.bmj.com/content/336/7635/88?variant=pdf&sso=
http://emupdates.com/2009/01/03/664-features-of-tension-headache-causes-of-subarachnoid-hemorrhage-what-of-the-population-has-a-berry-aneurysm-diseases-associated-with-berry-aneurysm/ http://www.bmj.com/content/340/bmj.c1305
http://www.doctors.net.uk/ecme/wfrmNewIntro.aspx?moduleid=1517

Cluster Headaches

Cluster headaches are severe unilateral headaches. They used to be called migranous neuralgia. They are short lasting and are accompanied by autonomic symptoms. Less than 1% of patients have cluster headache, and it affects men more than women (3- 6 times more), and young people (in their 30s) rather than old people. 85% of patients smoke. They present similarly in men and women, but women tend to have more migrainous type symptoms. Alcohol, nitroglycerine, exercise, and elevated environmental temperature are recognized precipitants of acute cluster attacks.


Symptoms
- Short bouts of pain, lasting weeks or months
- Bouts may occur up to eight times a day
- Follow a circadian rhythm, with a 24hour cycle
- One sided in the orbital, supraorbital or temporal regions
- Associated with autonomic symptoms (ptosis, miosis, eye watering, bloodshot eye, runny nose, blocked nose).
- Autonomic symptoms occur on the same side as the pain

Official Diagnosis
A diagnosis of cluster headache is supported by at least five attacks that fulfil the following criteria:
Severe pain on one side in the orbital, supraorbital, or temporal region which lasts 15 to 180 minutes if left untreated.
At least one of the following on the same side:
   Bloodshot or watery eye
   Blocked or runny nose
   Eyelid oedema
   Forehead and facial sweating
   Miosis or ptosis, or both
   A sense of restlessness or agitation
Attacks that occur every other day at a frequency of up to eight per day
Other causes have been excluded.

Migraine vs Cluster Headache

 Alcohol induces cluster headache quickly, migraines some hours after.

Treatment
To manage patients with cluster headache you should treat the acute attack and consider prophylaxis against further attacks

Oxygen
- 100% via non re-breath mask for at least 20 minutes
- 60% of patients respond to oxygen therapy
- More beneficial at the onset of symptoms

Sumatriptan
- 6mg sc sumatriptan relieves pain in 20minutes in 75% of patients
- Oral triptans are too slow
- Triptans contraindicated with cardiovascular, cerebrovascular disease and untreated arterial hypertension. Do NOT use with MAOIs or ergotamines.
- Side effects include chest pain and distal paraesthesiae.

Ergotamines
Oral ergotamine has been used to treat cluster headache for more than 50 years, but there is little evidence available to support its effectiveness.

Lidocaine
Applying lidocaine nasally is effective in about one third of patients. The suggested dosage is 1 ml with a concentration of 4-10%, given on the same side as the pain. The patient should lie back with their head turned to the affected side after application. Most of these studies are small, and the effect is unlikely to be clinically beneficial.

Steroids
Up to 80% of patients with cluster headache respond to steroids. Start with 60-100 mg of prednisolone once a day for at least five days. After this you should try to decrease the dosage by 10 mg every day.

Third Line Treatment
Pizotifen, valproic acid, topiramate and capsaicin. Prevent with verapamil or lithium.

Follow Up
It is recommended that patients attending with cluster headaches should be followed up in neurology outpatients for consideration of further imaging as there is a link with pituitary adenoma.

Paroxysmal hemicrania
Paroxysmal hemicrania is rare. It is similar to cluster headaches but patients have shorter, more frequent attacks. They have a good response to indomethacin. This is one of the diagnostic criteria. Within three to seven days of starting indomethacin at an adequate dosage the attacks disappear. The usual dose is 50 mg three times per day. It is worth trying a trial of indomethacin even if the headache is not typical of paroxysmal hemicrania; if patients are going to respond, they will do so quickly.

http://www.enlightenme.org/learning-zone/doc-my-head-hurts
http://www.bmj.com/content/344/bmj.e2407
http://jnnp.bmj.com/content/70/5/613.full
http://www.pn.bmj.com/content/1/1/42.full.pdf
http://www.bmj.com/content/344/bmj.e2407.pdf%2Bhtml
http://n3.learning.bmj.com/learning/modules/flow/JIT.html?execution=e1s1&_flowId=JIT&moduleId=5004479&status=LIVE&locale=en_GB&action=start&sessionTimeoutInMin=90
http://cks.nice.org.uk/headache-cluster
http://publications.nice.org.uk/headaches-cg150
http://www.sign.ac.uk/guidelines/fulltext/107/index.html