EM guidemap - Headache Click on any of the headings or subheadings to rapidly navigate to the relevant section of the guidemap
When should an EP consider, and exclude, a subarachnoid hemorrhage?
When should an EP consider, and exclude, meningitis?
When is a CT scan of the head indicated in an ED headache patient?
What should an EP do next if the CT scan of the head is negative (or not clinically indicated)?
What other serious causes of a secondary headache should an EP consider?
How can an EP differentiate the different primary headache syndromes?
How should an EP treat a primary headache disorder in the ED? Appendix
- ice-pick headache
- cough headache
- benign coital headache
- hypnic headache syndrome
- analgesic rebound headache
Introduction - this guidemap is specifically designed to help EPs problem-solve the clinical problem of acute headache in an ED setting
- although the majority of ED headache patients have benign causes of their headache, a prudent EP should first consider, and exclude, many serious causes of a secondary headache by a careful history, targeted examination and selective diagnostic testing
- this guidemap is divided into a series of sections specifically designed to answer specific questions:-
- this guidemap does not provide much background information on diseases causing a secondary headache => this guidemap is mainly targeted toward ensuring that an EP considers, and excludes, serious causes of a secondary headache
- when should an EP consider, and exclude, a subarachnoid hemorrhage?
- when should an EP consider, and exclude, meningitis?
- when is a CT scan of the head indicated in an ED patient?
- what should an EP do next if the CT scan of the head is negative?
- what other serious neurological causes of a secondary headache should an EP always consider?
- how can an EP differentiate between the different primary headache syndromes?
- how should an EP treat a primary headache disorder?
When should an EP consider and exclude a subarachnoid hemorrhage? - all EPs would consider the possibility of a subarachnoid hemorrhage if a patient presented to the ED with a thunderclap headache (sudden, severe headache that develops within seconds and achieves maximal intensity within a few minutes) that is temporally related to exertion - especially if the patient also had altered mental status and/or meningism and/or focal neurological signs
- however, many subarachnoid hemorrhage patients (20 - 50%) present initially with sentinel bleeds that produce sudden onset headaches ("warning" headaches) that are less intense in nature, and which are not not associated with altered mental status or meningism, and that may not be precipitated by exercise
- there are no characteristic features of a sentinel headache and a prudent EP would consider a subarachnoid hemorrhage workup if a headache patient had any of the following clinical presentations:-
(* benign coital headaches can mimic a sentinel headache and the diagnosis of benign coital headache can only be made if the patient has a known history of benign coital headaches and if the headache pattern is identical to previous episodes of benign coital headaches => see the appendix for further details about benign coital headache)
- sudden onset headache of moderate/severe intensity
- "worst" headache of his life
- "first" severe headache of his life
- "new onset" headache in a patient with a history of migraine that is more severe (or very different in character) than the usual primary headaches - especially if the headache is of sudden onset ("crash" migraine)
- any headache that develops suddenly during exertion or coitus
- any headache associated with transient loss of consciousness or buckling of the legs
- patient has a very strong family history of cerebral aneurysms or SAH
- patient has a personal history of having had a previous SAH
- patient has a history of polycystic kidneys or heritable connective tissue disease eg. fibromuscular dysplasia
- sub-hyaloid hemorrhages seen on fundoscopy
- "new onset" headache or posterior neck pain, which radiates down the neck and back (interscapular area)
- any headache or posterior neck pain + "subtle" meningism
- any headache/peri-orbital pain associated with a pupil-involving third nerve palsy
- any severe headache in a patient with a bleeding diathesis or known AVM
- any headache + a multiplicity of 'soft" neuro signs eg. diplopia, subtle focal neurological signs
- if an EP suspects an subarachnoid hemorrhage, what is the optimal diagnostic approach?
- a non-contrast CT scan of the head using 3mm cuts through the base of the brain is usually the first diagnostic procedure perfomed because it is 90 - 98% sensitive in the first 12 - 24 hours, and it is non-invasive and quick to perform
- however, a CT scan can be falsely negative if (i) the sentinel bleed is very small, or (ii) if the CT scan is performed long after the onset of symptoms (> 95% sensitivity if performed within 12 hours, 85% sensitivity after 3 days, 70% sensitivity after 5 days and 50% sensitivity after 7 days), or (iii) if the patient is very anemic (hemoglobin < 10g/dl), or (iv) if motion artefacts result in a sub-optimal CT scan study, or (v) if the scan quality is technically poor (thick cuts, old-generation scanner), or (vi) if the radiologist is inexperienced or incompetent
(* a standard MRI is diagnostically superior to a CT scan a few days after a sentinel bleed, but has no diagnostic advantage in the first 24 hours and may even be less sensitive for the acute detection of blood)
- a LP should always be performed if the CT scan is negative because the CT scan is negative in ~ 5% of patients with a classic thunderclap headache presentation, and in an unknown number of patients with an early onset sentinel bleed
(* the sensitivity of a CT scan depends on spectrum bias - amount of blood present in the CSF space - which cannot be a priori determined; a LP should also be performed if the CT scan is technically inadequate or equivocal)
- a LP should definitely be performed if the patient presents a few days days after the onset of a thunderclap headache because the sensitivity of a CT scan decreases with the progression of time, while a LP will still be 100% positive for xanthochromia for 1 - 2 weeks after the onset of the headache
- there is controversy as to when a LP should first be performed, because xanthochromia may take 6 - 12 hours to develop => if a LP is performed within the first few hours after the onset of a sudden headache, the LP may be falsely negative because there may be no xanthochromia and sufficient blood may not have reached the lumbar area if the sentinel bleed is very small
(* it is important to remember that xanthochromia is only visibly detectable by the naked eye in ~ 50% of xanthochomic-positive cases and that routine spectrophotometric analysis of the CSF supernatant is therefore advisable; however, because most hospitals do not have spectrophotometric CSF analysis available => fill another test tube with water and compare the patient's CSF to the control tube to optimize simple visual detection)
- there is also the problem of differentiating a traumatic tap from a true subarachnoid hemorrhage if the LP is performed too early (before the development of xanthochromia) => the "three-tube method" of progressively decreasing RBC counts is apparently not entirely reliable in differentiating between a traumatic spinal tap and a subarachnoid hemorrhage; also, if a second confirmatory spinal tap is delayed a few hours => xanthochromia may occur from the initial traumatic tap and confound the diagnostic situation
(* remember that a positive tap is variably defined as the presence of RBCs or xanthochromia - although many experts regard xanthochromia as the critical diagnostic element)
- a LP can be used as the primary (first) test => this will significantly decrease the number of CT scans that will need to be performed and decrease the costs of diagnostic testing; it will also decrease the number of cases when physicians-or-patients unwisely decide to abort the diagnostic process and forgo the LP when the CT scan is negative + the headache spontaneously resolves (or is relieved by adequate analgesic therapy)
- however, the disadvantages of using a LP as the primary diagnostic test are:-
- if the CT scan + LP are both negative => a subarachnoid hemorrhage is reliably excluded
- it may need to be delayed 6 - 12 hours from headache onset to be 100% sensitive (or it may need to be repeated if initially negative)
- it is invasive and painful and has associated complications (post-spinal headache) that could be avoided in a minority of cases if a CT scan was performed first and was positive for a subarachnoid hemorrhage
- there is the small, but significant, problem of diagnostic confusion resulting from traumatic taps if the LP is done too soon after the headache onset
- there is the small risk of missing other intracranial pathology that could be detected by a CT scan (cerebral venous sinus thrombosis, bilateral subdural hematomas)
- possible increased risk of re-bleeding in SAH patients - by increasing the pressure gradient across the aneurysmal wall
- there is an extremely small risk of tentorial herniation in the alert patient with no focal neurological signs - however, remember that a LP is contraindicated prior to a CT scan if the patient has clinical signs of increased intracranial pressure or gross papilledema on fundoscopy
- MRI angiography/4-vessel cerebral angiography after a negative CT scan + negative LP may still be indicated if a clinician still has a strong suspicion of a cerebral aneurysm:-
If unsure how to proceed => consult a neurologist to optimize decision-making
- an absolutely "classic" thunderclap headache presentation
- headache + meningism and/or altered LOC, headache + pupil-involving third nerve palsy
- very strong family history of cerebral aneurysms
- patient history of a previous SAH
- subhyaloid hemorrhages visible on fundoscopy
- the CT scan/LP were delayed and only performed > 2 weeks after a suspected sentinel bleed
- CT scan or LP results are equivocal or uninterpretable
When should an EP consider, and exclude, meningitis? - a patient with a headache + fever + neck stiffness + altered mental status => meningitis until proved otherwise => perform stat blood cultures => administer a stat loading dose of appropriate IV antibiotics => proceed with diagnostic testing to exclude meningitis
- a LP can be delayed a few hours without affecting the diagnostic accuracy of the spinal tap; patient stabilisation should precede a LP
- a CT scan only needs to precede a LP if the patient is significantly obtundant, or has other evidence of increased intracranial pressure, or if an intracranial mass lesion is strongly suspected (eg. brain abscess in a HIV positive patient) or if the patient has focal neurological signs
- if the patient does not have "classic" clinical signs of meningitis, consider a LP to r/o meningitis in a patient with:-
- severe headache + high fever
- headache + fever + any altered mental status
- headache + fever + any degree of meningism
- headache + fever + seizure
- headache in a HIV-positive patient (even in the absence of a fever)
- headache + fever + known primary (extra-cranial) infective source if the headache is severe or progessive, or if the patient appears disproportionately "toxic"
- headache + fever + close contact with an index patient with known bacterial meningitis
When is a CT scan of the head indicated in an ED headache patient? - a CT scan of the head is obviously indicated in the diagnostic workup of a patient with a suspected subarachnoid hemorrhage if the LP-first approach is not adopted
- other indications for performing a CT scan of the head in an ED patient presenting with a headache (if a subarachnoid hemorrhage or meningitis is not suspected) could include:-
* Brain abscess is suspected if the patient has a headache + fever + peri-cranial infection, or known endocarditis, or pulmonary infection +/- is immunosuppressed and then develops an increasingly severe headache +/- focal neurological signs +/- altered LOC; fever and abnormal neurological signs may be absent during the early stages or if the patient is immunosuppressed
- headache + any altered mental status
- headache + any focal neurological signs
- headache + vertigo + ataxia (cerebellar bleed, vertebral artery dissection, posterior fossa tumor)
- headache + gait apraxia + incontinence (chronic subdural hematoma, hydrocephalus)
- headache + any degree of papilledema on fundoscopy (increased intracranial pressure)
- headache + seizure
- headache + multiple "soft" neurological signs
- headache + any recent head injury
- headache + well-anticoagulated/over-anticoagulated patient
- headache + significant bleeding diathesis (eg. hemophilia)
- any subacute headache that is progressive and unresponsive to standard analgesic therapy (? brain tumor)
- any headache that is distinctly worse when straining, or coughing, or bending, or on early morning awakening (? brain tumor, other space occupying lesion, cerebral venous sinus thrombosis or pseudotumor cerebri)
- any "new onset" headache in a patient > 50 years, especially if inexorably progressive (? brain tumor)
- any persistent "side-locked" headache that never changes sides
- any headache that is associated with projectile vomiting, or disproportionate vomiting that is not readily explained by migraine or systemic illness (? space occupying lesion or other cause of increased ICP)
- any "new onset" headache in a HIV-positive (or severely immunocompromised) patient
- any persistent "new onset" headache + known underlying malignancy
- if a brain abscess is strongly suspected (contrast CT scan is the optimal study)
- strong suspicion of sphenoid sinusitis, pituatry apoplexy or cavernous sinus thrombosis
* Sphenoid sinusitis should be suspected if the patient has a severe/relentless vertex headache aggravated by activity or coughing + visual blurring + fever +/- previous signs of sinusitis; late complications include signs suggestive of cavernous sinus thrombosis - frontal/retro-orbital pain, chemosis, proptosis, diplopia, decreased visual acuity or visual field deficits, and cranial nerves 3, 4, 5 (first and second division) and 6 involvement
* Pituatry apoplexy is suggested by a sudden vertex headache + bitemporal hemianopia +/- extraocular muscle palsies
- an EP who feels under pressure to always order a CT scan in every ED headache patient to r/o a brain tumor should recall that the Quality Standards Subcommittee of the American Academy of Neurology issued the following clinical practice guideline:- "Neither CT scan nor MRI is warranted in adult patients whose headaches fit with the broad definition of migraine and who have not demonstrated any recent substantial change in headache pattern, occurrence of seizures, or presence of focal neurological symptoms or signs"
What should an EP do next if the CT scan of the head is negative (or not clinically indicated)?
- if there is no evidence of a subarachnoid hemorrhage or meningitis + CT scan is negative in an ED patient with a secondary headache (or if there were no clinical indications warranting a CT scan) => you should always consider (or re-consider) a number of serious diagnostic possibilities that may not be readily diagnosable by CT scan
- benign intracranial hypertension (pseudotumor cerebri)
- cerebral venous sinus thrombosis
- carotid artery or vertebral artery dissection
Clinical clues that may make you suspect benign intracranial hypertension or cerebral venous sinus thrombosis
Diagnosis Clinical clues Benign intracranial hypertension (also called idiopathic intracranial hypertension, or pseudotumor cerebri)
- obese young female
- headache worsened by bending or straining or coughing
- retrobulbar pain worsened by eye movements
- transient visual obscurations (70%)
- diplopia (40%)
- enlarged blind spot => tunnel vision
- infero-nasal visual field defects
- isolated papilledema (+++)
- absence of any neurological signs - except 6th nerve palsy
- pulsatile intracranial noises (60%)
- decreased sense of smell
- may be associated with drug use (vitamin A, tetracycline, oral contraceptives, steroids)
- normal CT scan, or empty sella sign +/- dilated optic nerve sheaths on CT scan
Cerebral venous sinus thrombosis
- peri-cranial infections (sinusitis, otitis media, mastoiditis, odontogenic)
- pregnancy or peri-partum period
- oral contraceptives
- underlying malignancy
- connective tissue diseases (especially Behcet's syndrome)
- hypercoagulable disorders
- inflammatory bowel disease
- internal jugular vein catherisation/thrombosis
- severe, non-localised headache (+++)
- papilledema (45%)
- focal hemiplegia (35%)
- seizures (30%)
- if you suspect benign intracranial hypertension or cerebral venous sinus thrombosis => perform an LP and measure the opening pressure => an opening pressure > 200mm water should be regarded as elevated and a small amount of additional CSF fluid should be removed prior to completing the spinal tap => consult a neurologist to decide on further testing if the patient has an elevated CSF pressure (which is compatible with either of those two entities)
(* a venous phase MRI with gadolinium enhancement may detect a cerebral venous sinus thrombosis, which is only definitively detectable in a minority of patients using a routine CT scan of the head; 80% of CT scans in patients with cerebral venous sinus thrombosis may have non-specific changes - diffuse cerebral edema + small ventricles, hemorrhagic venous infarcts, enhancement of the falx and tentorium, thrombosed cortical veins)
- the possibility of carotid artery or vertebral artery dissection should always be kept in mind, but this is an extremely difficult diagnosis to make if the headache precedes any neurological abnormalities by days-to-weeks
- an EP should think of carotid artery dissection in any young patient (20 - 40 years of age) who has a combination of face + fronto-temporal area pain (or antero-lateral neck + temporal area pain) => look carefully for subtle ptosis and/or miosis due to a partial Horner's syndrome and listen carefully for neck bruits => re-question the patient carefully about any recent trivial neck trauma (eg. mountain bike riding on rocky terrain, sporting activities or gymnastics, forceful sneezing or nose blowing, or any activity causing excessive neck movements) or any transient neurovisual TIA-type symptoms
(* the visual symptoms of carotid artery dissection can mimic scintillating scomata and up to 20% of patients also have a history of migraine, but the scintillating scotomata associated with carotid artery dissection are often maximal at their onset, do not "march" and last longer than one hour)
Consider carotid artery or vertebral artery dissection if the following clinical features are present:-
Clinical clues that may make you suspect carotid artery or vertebral artery dissection
Diagnosis Clinical clues Carotid artery dissection
- younger patient
- history of fibromuscular dysplasia, cystic medial necrosis, Marfans syndrome (15 - 20%)
- hypertension (30%)
- recent minor neck injury (40%)
- unilateral peri-orbital/fronto-temporal pain, face, lateral neck pain
- ipsilateral painful partial Horner's syndrome (anhidrosis absent)
- ipsilateral neck bruits
- ipsilateral pulsatile tinnitus/head noises
- immediate or delayed anterior circulation focal neurological signs
- cranial nerve palsies rare (12th => 11th, 9th, 10th, 5th)
Vertebral artery dissection
- preceding violent neck movement more common (80%)
- recent chiropractic manipulation, gym workout, judo
- younger female patient (70%)
- severe unilateral posterior occipital/upper neck pain
- posterior neck bruit
- immediate or delayed neurological symptoms common
- partial or complete lateral medullary syndrome (vertigo, vomiting, nystagmus, dysequilibrium or ataxia, Horner's syndrome, ipsilateral facial or peri-orbital dysesthesia => diplopia, hemiparesis, unilateral face weakness, tinnitus, dysarthria, dysphagia)
- if the clinical syndrome suggests a carotid artery or vertebral artery dissection => consult a neurologist and arrange for appropriate imaging studies (usually Doppler sonography or MRI angiography or s-CTA or conventional angiography if a standard (non-contrast) CT scan has already been performed and was negative)
- after considering all those serious causes of a secondary headache, it may be worthwhile to use a final checklist to consider a few more causes of secondary headache that you may occasionally forget to consider
Checklist of some causes of secondary headaches
Diagnosis Clinical clues Carbon monoxide poisoning
- throbbing vascular-type headache
- nausea and vomiting
- other family members afflicted (case clustering)
- exposure history available
- consider other vasodilating drugs (eg. alcohol, nitrates, caffeine) if carbon monoxide exposure history not present
Acute angle closure glaucoma
- "red" eye
- peri-orbital pain
- impaired vision
- poorly reactive pupil
- cloudy (lacklustre) cornea
- shallow anterior chamber
- high intraocular pressure
Cerebral arteritis
- elderly patient (> 60 years)
- new onset localised headache or face pain (often dull and boring, may be throbbing +/- superimposed ice-pick pains)
- jaw claudication
- localised scalp tenderness
- scalp pain worse when laying head on a pillow, or when combing hair
- superficial temporal artery tenderness
- decreased superficial temporal artery pulsation
- polymyalgia rheumatica +/- systemic symptoms
- TIAs or amaurosis fugax or ischemic optic neuropathy
- elevated sed rate
Malignant hypertension
- usually markedly hypertensive (diastolic > 120 - 140 mmHg)
- grade 3/4 hypertensive retinopathy
- altered mental status common
- consider an underlying hyperadrenergic crises due to pheochromocytoma, cocaine or amphatamine abuse, or MAOI-other drug interaction
- severe hypertension in the absence of an encephalopathy could be a secondary phenomenon, and is often a "red herring" that may result in an EP not actively pursuing other diagnoses
Medical diseases
- febrile illness/infection
- sinusitis
- vasculitis (SLE, polyarteritis nodosa)
- polycythemia
- hyponatremia
- hypoxia or hypercarbia
- drug-induced (nitrates, NSIADs, anti-hypertensives, vasodilators, H2 blockers, hormones, antibiotics, cocaine, volatile hydrocarbons, monosodium glutamate)
- drug-withdrawal (alcohol, caffeine)
- if a patient with a secondary headache has no clinical evidence of subarachnoid hemorrhage, meningitis, cerebral venous sinus thrombosis, benign intracranial hypertension, carotid/vertebral artery dissection, carbon monoxide poisoning, malignant hypertension or cerebral arteritis + there are no indications to perform a CT scan of the head to r/o other pathology eg. strokes, intracranial bleeds, brain tumor (or if the CT scan is negative for intracranial pathology) => treat the patient symptomatically and give the patient appropriate discharge instructions
- all headache patients discharged from the ED should be encouraged to return to the ED if:-
- the headache worsens dramatically
- there is any change in mental status
- they develop any neck stiffness
- they develop any focal neurological signs
- they become ataxic and cannot ambulate
How can an EP differentiate the different primary headache syndromes? - the characteristic feature of a primary headache syndrome is that it is always associated with recurrent headaches
- common primary headache syndromes include migraine, cluster headache, tension headache and chronic daily headaches
- these headache syndromes have precise diagnostic definitions and it is important that an EP not use the term 'migraine' non-specifically to describe any chronic headache
- divided into two types:- migraine with aura (previously called "classic" migraine) and migraine without aura (previously called "common" migraine)
- both types of migraine patients may report prodromal symptoms (hyperactivity, mild euphoria, lethargy, depression, craving for certain foods, frequent yawning) that begin 24 - 48 hours prior to an attack
- prodromal symptoms should not be confused with the aura, which usually precedes the headache by 1 - 2 hours and lasts < 60 minutes
- complicated migraine (migraine with a prologed aura) is defined as a migraine attack associated with an aura lasting > 1 hour and < 1 week + normal neuroimaging study
- migrainous infarction refers to a prolonged aura that persists for longer than one week due to a cerebral infarction
- status migrainosus refers to migraine heaches that last longer than 72 hours despite treatment
- familial hemiplegic migraine should be suspected if a hemiplegic aura persists for weeks in a patient with a strong family history of similar migraine presentations (autosomal dominant)
- opthalmoplegic migraine consists of a third nerve palsy (ptosis + mydriasis + opthalmoplegia) that may appear before/after the headache and persist for weeks, and it usually begins in childhood
Criteria for the diagnosis of migraine with aura
A. Migraine headache is preceded by at least one of the following auras (neurological symptom complexes) which have at least 3 of the following 4 criteria: - i) aura is fully reversible, ii) aura develops gradually over > 4 minutes, iii) aura does not last > 60 minutes, iv) aura is followed by a headache in < 60 minutes or the aura may occur during the headache
- visual aura
- focal aura
- scintillating scotomata (expanding scomata with scintillating border consisting of shimmering zig-zag patterns that starts as a hazy spot in the center of one visual hemifield => expands slowly over ~ 20 minutes as it moves to the periphery of the involved half of the visual field and disappears over the edge)
- fortification spectra (expanding C-shaped paracentral scotoma with serrated edges resembling a "fortified town with bastions all around it")
- photopsia (unformed flashing lights)
- teichopsia (bright shimmering or wavy lines)
- macropsia or micropsia (distortions of size)
- metamorphopsia (distortions of size or shape)
- negative phenomena (bilteral scotomas that may be a complete homonymous hemianopia, a quadrantic field defect, an altitudinal or central scotomata or even total blindness) => monocular scotomas should be regarded as non-migraine until proved otherwise and the patient requires a meticulous workup
B. No evidence of neurological disease (eg. cardiogenic emboli, carotid artery dissection, arteritis - especially associated with SLE, hypercoagulable states and and sickle cell disease may mimic complicated migraine and produce a headache + TIA - usually the TIA is abrupt in onset and does not "slowly march" and it does not usually involve multiple modalities eg. visual scintillation displays + sensory paresthesias +/- hemiplegia)
- unilateral numbness/paresthesia (often cheiroaural starting in the hands and then "slowly marching" up the arms and then jumping to the face and lips and around the mouth over 10 - 20 minutes - slower progression than a TIA)
- unilateral weakness or limb heaviness
- dysphasia or other language disturbance (may be associated with upper limb heaviness)
- basilar symptoms - vertigo, tinnitus, dysarthria, fluctuating deafness, ataxia, bilateral weakness, +/- temporary confusion or sensorial clouding +/- total blindness (basilar migraine may occur without any headache and be mistaken for a psychosis - seen more commonly in adolescent or young adult females)
Criteria for the diagnosis of migraine without aura
A. Migraine headache lasting 4 - 72 hours (untreated or unsuccessfully treated)
B. Two of the following
C. During the migraine headache, at least one of the following occurs
- unilateral location
- pulsating quality
- moderate or severe intensity
- aggravated by routine physical activity
D. Both of the following
- nausea and/or vomiting
- photophobia and/or phonophobia
- a major clue that suggests migraine is the patient's age - migraine commonly starts when the patient is a teenager or young adult (female:male = 3:1) and very rarely starts in middle age or beyond; and there is often a strong familial history of similar headaches
- similar headaches in the past
- no evidence of organic disease
- classical migraine often starts as an unilateral, aching or throbbing pain in the fronto-temporal area, which may then radiate to the occipital area and then become more diffuse, bilateral and aching (or more throbbing)
- patients prefer to lie still and avoid activity and sleep may result in resolution of the headache
- migraine may rarely present with a very sudden headache ("crash" migraine) mimicing a subarachnoid hemorrhage and mandating a subarachnoid hemorrhage exclusionary-workup
- it is very rare for a first attack of migraine to present as complicated migraine eg. basilar migraine => always presume that the cause is cerebrovascular disease until proved otherwise
Diagnostic criteria
A. Severe unilateral orbital or periorbital pain lasting 15 - 180 minutes with a maximum number of 8 attacks per day
B. At least one of the following ipsilateral to the headache
C. No evidence of organic disease
- conjunctival injection
- lacrimation
- nasal congestion
- rhinorrhea
- facial sweating
- miosis
- ptosis
- eyelid edema
- cluster headache is more common in males (> 5:1) and in the 20 - 40 year old age group
- cluster headaches usually occur in daily bouts (or almost daily) of 1 - 8 episodes per day for an active cluster period of 2 weeks - 3 months
- remission periods should last at least 2 weeks, but usually last months or years
- the pain is usually excruciating and stabbing and penetrating in nature (non-throbbing) and situated in the territory of the trigeminal nerve, and the patient may often moan-and-cry in desperation because the pain is so intense and the patient will not usually lie quietly in bed => the patient often paces about relentlessly and bangs his head in desperation (in contrast to a migraineur, who prefers to lie quietly in a darkened room)
- the cluster headache is always unilateral and may be "locked" to the same side during every attack and every cluster period, and one of daily cluster episodes may occur at the same time every night at 2 - 3 am (alarm-clock headache)
- chronic cluster headache syndrome occurs infrequently (< 10% of cases) and there are no remission periods; chronic cluster headache syndrome may evolve from episodic cluster headaches or may be unremitting from the onset
- cluster headaches may be provoked by alcohol, or histamine or nitroglycerine - but only during the active cluster period
- the first episode of cluster headache (face/temporal area pain + ptosis/miosis) may mimic a carotid artery dissection, which is not associated with the other autonomic features (rhinorrhea, nasal stuffiness, excessive lacrimation, conjunctival injection)
- the Horner's syndrome associated with cluster headache may persist between attacks
IHS criteria for different types of tension headache include:-
Tension-type headache
A. At least two of the following pain characteristics
B. Both of the following
- pressure/band-like tightening (non-pulsating) quality
- mild or moderate intensity (may inhibit but does not prohibit activities)
- bilateral location
- no aggravation by walking stairs or similar activity
C. At least one of the following
- no nausea or vomiting (anorexia may occur)
- phonophobia or photophobia are absent, or one but not the other is present
Episodic tension-type headache
- history and physical examination does not suggest a secondary headache
- history and physical examination does suggest a secondary headache, but it is ruled-out by appropriate investigations
- a secondary headache is present, but a tension-type headache does not occur for the first time in close temporal relationship to the secondary headache
Diagnostic criteria
A. At least 10 previous headache episodes + number of days per year with such a headache is < 180/ year (< 15/month)
B. Headache lasts 30 minutes - 7 days
Chronic tension-type headache
Diagnostic criteria
A. Average headache frequency > 15 days/month for > 6 months
- daily or near-daily headache lasting > 4 hours/day for > 15 days/month
- typical patient is a young female in her 20 - 40s, who also has associated depression and/or anxiety
- four subtypes:- transformed migraine, chronic tension-type, new daily persistent headache, hemicrania continua
Transformed migraine
- typically the patient describes a history of distinct attacks of migraine, which start during her teens or early 20s, and which eventually become more frequent
- in addition, the patient develops interparoxysmal tension-type headaches, which also become more frequent => daily or near-daily headaches
- there is a definite tendency for this subgroup of female migraineurs to have worsening headaches perimenstrually with relief during pregnancy
- analgesic/ergotamine overuse may be a significant factor
Chronic tension-type headache
- most occur through gradual transformation from episodic tension-type headache to a chronic pattern over a period of time
- factors that may result in this transformation include:- analgesic or ergotamine overuse, comorbid disorders - anxiety and/or depression, abnormal personality profile, family-life or work-related stress
Comparison of clinical characteristics of transformed migraine
and chronic tension-type headache
Transformed migraine Chronic tension-type headache
- previous history of distinct migraine attacks
- no history of distinct migraine attacks
- increased incidence of headache in the family
- positive family history less important
- retains migrainous characteristics to a significant degree, intermittently or continuously
- migranous features absent or very insignificant
- increased neurological and gastrointestinal symptoms
- neurological and gastrointestinal symptoms minimal
- menstrual aggravation
- no particular aggravation during menstruation
- more relief during pregnancy
- less relief during pregnancy
- excessive intake of analgesics common
- excessive intake of analgesics common
- responds to anti-migraine therapy
- response to anti-migraine therapy occurs, but less strikingly
- behavioral and psychological factors prominent
- behavioural and psychological factors prominent
New daily persistent headache
- rapid onset of a daily persistent headache that continues on a daily basis + no previous history of episodic tension-type headaches
- this entity is not clearly understood
Hemicrania continua
- unusual headache syndrome consisting of constant unilateral headache of moderate-to-severe intensity + unprovoked brief episodes of sharp jabbing pain in a similar location (shorter duration than cluster headaches
and paroxysms occur 12 - 20x per day + no accompanying autonomic symptoms)- always responds to indomethacin
How should an EP treat primary headache disorders in the ED? - an EP should resist the tendency to simply treat migraine and cluster headaches with narcotic analgesics => it is better to use targeted therapy directed at the etiology of the disorder
- many patients with migraine headache have already used immediate relief medications (acetaminophen and NSIADs' and narcotics) orally at home +/- po triptans +/- migraine prophylactic regimens
- the optimum approach in the ED is to use parenteral medication - preferably by the IV route - using a step-wise approach
Treatment of migraine in the ED setting
- there are different approaches and an EP can select from one of the three following approaches:-
1) Start with IV droperidol - 2.5mg over 2 minutes => repeat the IV dose of droperidol every 15 - 30 minutes to a maximum of three doses
- it is unknown how droperidol works in migraine and it is unknown whether it is better than DHE
(* there are very few studies of droperidol use in migraine and all the studies are small; droperidol is associated with a prolonged QT interval and torsade des pointes => the drug manufacturer recommends that an ECG be performed prior to using droperidol to first exclude a prolonged QT interval)
- droperidol is a powerful anti-emetic and additional anti-emetic agents will not be required
- droperidol causes akathisia (marked restlessness, state of inner agitation) or acute dystonia in a significant number of patients => it would be advisable to always use benadryl or benztropine mesylate simultaneously IV to try and decrease the incidence of akathisia
(* see the akathisia guidemap or drug-induced dystonia guidemap for further details)
- rapid bolus administration can cause hypotension and caution is advisable in the elderly/dehydrated patient
- repeated IV doses of droperidol is rarely associated with QT interval prolongation and torsade des pointes
2) Start with 10mg of metoclopramide or 10mg of prochlorperazine IV over 2 minutes => give 1mg of dihydroergotamine (DHE) IV over 2 minutes if there is no response to the anti-emetic agent within 20 minutes
- many patients respond to metoclopramide or prochlorperazine and do not require DHE; prochlorperazine may be more effective than metoclopramide as the first-line agent
- both prochlorperazine and metoclopramide are associated with extra-pyramidal side-effects (dystonia) and akathisia, and prophylactic administration of an anticholinergic agent is recommended
(* see the akathisia guidemap or drug-induced dystonia guidemap for further details)
- DHE cannot be given alone because it aggravates nausea and vomiting => an antiemetic must be given before DHE, or simultaneously with DHE (mix 10 mg of prochlorperazine and 1 mg of DHE in a syringe and give IV over 2 minutes)
- some physicians recommend using two 0.75mg doses of IV DHE sequentially => using the second dose after 20 - 60 minutes if there is no response to the first IV dose
3) Start with 6mg of sumatriptan sc
- does not require the use of an additional antiemetic agent
- rapid onset and may be as effective as the prochlorperazine/DHE combination
- patients have often administered sc sumatriptan at home and only one additional dose of sc sumatriptan can be administered within 24 hours; the two doses of sumatriptan must be given at least one hour apart
- the disadvantage of sumatriptan is that its beneficial effect is short-lived and rebound migraine headache is common (DHE is not associated with rebound headaches)
- DHE should not be used if a triptan has been used within the past 24 hours
- sumatriptan occasionally produces chest pain as a side-effect, and it is unknown whether the chest pain is related to coronary artery vasoconstriction => it is better to err on the side of caution and regard all post-sumatriptan administration chest pain as due to cardiac ischemia until proved otherwise (because there is no practical way to differentiate benign chest pain from triptan-induced cardiac ischemia)
- newer-generation triptans may have a faster onset of action, last longer and ? may cause less coronary vasoconstriction
- contra-indications to triptans and ergot preperations include:-
Chlorpromazine has been frequently used but it is associated with significant orthostatic hypotension (requiring pre-treatment IV saline fluid loading), excessive sedation, akathisia and other extra-pyramidal side-effects; it is probably also less effective than the other regimens
- known coronary artery disease, or multiple risk factors for CAD
- peripheral vascular disease
- uncontrolled hypertension
- previous stroke
- MAOI use within 2 weeks
- basilar or hemiplegic migraine
- age > 40 years
- pregnancy
- known drug hypersensitivity
A number of studies have stated that IM ketorolac compares favorably to IM meperidine in the treatment of acute migraine => however, meperidine is not very effective in acute migraine and I am sceptical whether any of those two agents should be used for the treatment of acute migraine attacks unless there are contra-indications to triptans/DHE and there is no beneficial effect from two 10mg doses of IV prochlorperazine given 30 minutes apart
Dexamethasone - 10mg IV followed by 4mg every 6 hours IV prn has been used in status migranosus
Consult the following online resource for further details regarding the managment of acute migraine
* http://www.aafp.org/afp/20001015/practice.html
* http://www.aafp.org/afp/20001101/practice.html
* http://www.aafp.org/clinical/migraine or http://www.aan.com/public/practiceguidelines/03.pdfTreatment of cluster headache in the ED setting
1) Oxygen inhalation by nasal cannula (or mask if there is significant nasal stuffiness) at ~ 8 litres/min for 15 minutes with the patient sitting upright is a first-line treatment
2) Sumatriptan (6mg sc) or the prochlorperazine/DHE regimen as used for the treatment of acute migraine if there is no response to oxygen inhalation therapy
3) Corticosteroids (8mg dexamethasone or prednisone 60 - 80mg/day po) for a few days followed by a two week tapering course - may help abort a bout of cluster headaches
4) Lithium carbonate, methysergide and verapamil are also used prophylactically
Appendix - single isolated jabs of pain or repetitive sharp, stabbing pains that are localised and momentary, or the pain may last a few seconds
- usually occur focally at the temporal area or orbit (area of the first division of the trigeminal nerve); 50% also occur at the mirror locus in the opposite hemicranium
- if repetitive, the paroxyms occur at the rate of one per second; while trigeminal neuralgia produces machine gun volleys of lancinating electric-like pain with each jolt of pain occurring in a fraction of a second (in the area of the second or third division of the trigeminal nerve)
- usually of benign etiology and may accompany primary headaches syndromes eg. migraine or cluster headache, or temporal arteritis
- frequency can be reduced by prophylactic treatment with indomethacin
- transient severe headache on coughing, sneezing, weightlifting, bending or stooping
- usually bi-occipital in location
- arises moments after a sufficient stimulus, reaches its peak almost immediately and subsides over seconds-to-minutes
- usually occurs in middle-aged/elderly men (male:female ratio = 4:1) and runs its course in a few years
- the first cough headache episode may require a r/o subarachnoid hemorrhage workup because it may not be possible to clinically differentiate it from a subarachnoid hemorrhage
- a posterior fossa brain tumor or Arnold-Chiari malformation causes the cough headache syndrome in 20 - 25% of cases, so timely MRI imaging is required in all cough headache patients (or ? only in patients who are < 40 years of age and/or who also have posterior fossa symptoms/signs)
- cough headache is inexplicably and remarkably ameliorated by indomethacin
- abruptly appearing, excruciating, throbbing occipital headache occurring just before, or at orgasm
- may also occur more gradually, building up slowly during the period of sexual excitement
- correlates poorly with the degree of sexual excitement and degree of physical effort expended
- may occur frequently or unpredictably (first occurrence often requires r/o subarachnoid hemorrhage workup)
- male:female ratio = 4:1
- usually lasts < 15 minutes, but may last a few hours
- consider a pheochromocytoma if the patient is very hypertensive during the recurrent episodes
- sudden headache awakening the patient (usually an elderly patient, and always > 65 years of age) at the same time every night, sometimes during a dream
- the headache is diffuse and persists for 30 - 60 minutes
- the headache is bilateral and not localised and there are no autonomic symptoms (unlike cluster headache)
- relieved by a bedtime dose of lithium carbonate
- defined as the perpetuation of head pain in chronic headache suffers by frequent and excessive use of immediate relief medications or a self-sustaining, rhythmic headache-medication cycle characterised by daily or near daily headache and irresistible and predictable use of immediate relief medications as the only means of relieving the headache
- the mere discontinuation of these analgesic medications (containing barbiturates or caffeine or ergots or narcotics) eventually results in significant improvement
- the headaches occur in patients with primary headache disorders who use immediate relief medications frequently and often in excessive amounts
- the patients have a low pain threshold and even minimal physical or intellectual effort may incite a headache; the headaches are often accompanied by asthenia, anorexia, nausea, restlessness, anxiety, irritability, difficulty in intellectual concentration and depression => however, patients are often capable of executing their normal social and occupational roles and do not have an addictive personality profile
- patients may develop signs of ergotism (cold extremities, hypertension, muscle pain in the extremities, distal paresthesias) due to chronic ergotamine use
- withdrawal symptoms occur when patients are taken off the medications abruptly (restlessness, sleeplessness, increased headache, diarrhea, seizures)
- the controlled withdrawal of medication may require inpatient admission and the use of repetitive IV doses of dihydroergotamine every 6 hours for 48 - 72 hours (or less optimally - chlorpromazine or prochlorperazine)
Disclaimer: My EM guidemaps reflect my personal approach to problem-solving/managing clinical cases in an ED setting and they should not be regarded as the standard of care. They merely represent the personal opinions of the author and they should only be used in clinical practice if the reader-user has substantial reason to believe that the clinical advice contained in the guidemaps is valid and accurate. The guidemaps are not meant to be "authoritative" and the reader-user should consult standard medical textbooks and expert opinion articles/guidelines for more authoritative advice. The reader-user should particularly confirm all drug doses, their indications and contra-indications, prior to their use.