DESCRIPTION

• Pain in the cranium, orbits, or upper neck
• Pain within the skull is projected to the surface:
  • Intracranial:
    • Arteries, veins, dura, meninges
  • Extracranial:
    • Skin, scalp, fascia, muscles
    • Mucosal linings of the sinuses
    • Arteries
    • Temporomandibular joints, teeth
• Pain is transmitted via the V cranial nerve.
• May be caused by a number of mechanisms:
  • Nerve irritation
  • Traction on pain-sensitive vessels
  • Vasodilatation of pain-sensitive vessels
    • Hypoxia, hypercapnia, fever, histamine injection, nitroglycerin ingestion
• Complaint in 2–4% of all ED visits:
  • 95% have a benign etiology (lower in patients older than 50 yr)
  • Life-threatening etiologies are rare and can be difficult to diagnose.

ETIOLOGY

• Migraine:
  • Intra/extracranial vasodilatation and constriction of pain-sensitive blood vessels
  • May also involve cortical depression
  • Throbbing headache
• Tension:
  • Requires ≥10 attacks of a similar nature
  • Unknown etiology (possibly serotonin imbalance, decreased endorphins, spasm)
  • Most common type of recurring headache
  • Triggered by poor posture, stress, anxiety, depression, cervical osteoarthritis
  • Bilateral, nonpulsatile, band like
  • Mild to moderate intensity
  • 4–13 hr duration
• Cluster headaches:
  • Triggered by alcohol, certain foods, altered sleep habits, strong emotions
  • May involve vasospasm near cranial nerves
• Intracranial (traction, pressure):
  • Mass lesions
  • Idiopathic intracranial hypertension
• Extracranial (compression):
  • Pathology causing pain in a peripheral nerve of the head and neck
• Inflammation:
  • Temporal arteritis
  • Cerebral vasculitis
• Thrombosis:
  • Cerebral venous sinus thrombosis (CVST)
• Impaired vascular autoregulation/endothelial dysfunction:
  • Posterior reversible leukoencephalopathy syndrome (PRES)
  • Reversible cerebral vasoconstriction syndrome (RCVS)

Pediatric Considerations

Serious causes of headache in children are rare but those who come to the ED for this complaint should all have follow-up with a pediatrician.

Geriatric Considerations

Older patients with new headache have a higher likelihood of a serious etiology and should have more thorough evaluation with a low threshold for imaging.

Pregnancy Considerations

In addition to all other causes of headache, pregnant women (and recently postpartum women) are at increased risk for CVST, eclampsia, PRES, and RCVS.

[Outline]

• DESCRIPTION
• ETIOLOGY

SIGNS AND SYMPTOMS

History

• Attributes of the pain—PQRST:
  • Provocative and palliative features:
    • Position of the head, coughing or straining (increase suggests elevated ICP), and movement
  • Quality:
    • Throbbing or continuous
    • Deep or superficial
    • Change compared to prior headaches
  • Region
  • Severity
  • Worst headache of life?
  • Timing
  • Sudden or gradual?
• Associated findings:
  • Visual symptoms, dizziness, nausea, vomiting
• Historical factors indicating additional testing:
  • New onset:
    • Age > 50
    • HIV, transplant, or cancer patient?
  • Trauma or falls (even without headstrike)
  • Persistent vomiting
  • Any new focal neurologic or visual symptoms
• Risk factors for cerebral sinus thrombosis:
  • Malignancy
  • Pregnancy (or postpartum)
  • Protein S or protein C deficiency
  • Oral contraceptive
  • Ulcerative colitis
  • Behçet syndrome

Physical Exam

• Complete neuro exam including cranial nerves, motor, sensation, deep tendon reflexes, gait
• Examine for papilledema.
• Evaluate skin for rashes:
  • Zoster
  • Purpura
• Palpate temporal arteries

ESSENTIAL WORKUP

• Detailed history, CNS, HEENT, and neck exam
• Factors indicating testing beyond the history and physical exam:
  • Severely elevated diastolic BP
  • Fever
  • Altered level of consciousness
  • Papilledema
  • Abnormal neurologic exam or meningismus

DIAGNOSIS TESTS & INTERPRETATION

Lab

• CSF:
  • Essential in suspected meningitis, subarachnoid hemorrhage (SAH)
• ESR:
  • If temporal arteritis or other inflammatory disorders suspected:
    • See Giant Cell Arteritis

Imaging

• Head CT scan:
  • Indications:
    • Uncertain diagnosis based on history and physical exam (leaving open the possibility of serious causes)
    • Signs of increased ICP
    • "First or worst" headache
    • Abrupt onset
    • New focal neurologic abnormalities
    • Papilledema
    • Recurrent morning headache
    • Persistent vomiting
    • Associated with fever, rash, and nausea
    • Trauma with loss of consciousness, focal deficits, or lethargy
    • Altered mental status, meningismus
  • Definitive test for SAH if performed within 6 hr of onset and read by an attending radiologist
  • Within 24 hr, > 95% sensitive (sensitivity falls rapidly with time and is 50% at 7 days out)
• Sinus imaging may show acute sinusitis; chronic sinusitis rarely causes acute headache.
• MRI:
  • Indicated to assess for etiologies that are missed by CT scan and LP:
    • Posterior fossa lesion
    • Pituitary apoplexy
    • CVST
• MRA:
  • Indicated if SAH suspected, CT is negative, and unable to perform lumbar puncture
  • Suspicion of carotid or vertebral dissection (e.g., recent neck manipulation or trauma)
  • Nonmigrainous vascular cause suspected (e.g., RCVS)

Diagnostic Procedures/Surgery

Lumbar puncture:

• Perform CT 1st if:
  • New focal neurologic finding
  • Papilledema
  • Abnormal mental status
  • HIV positive or immunosuppressed
• Detect intracranial and meningeal infections
• Detect blood not evident on CT scan:
  • There is no specific threshold number of red cells below which SAH is excluded – the RBC count is a function of time from onset.
• Opening pressure:
  • Essential to diagnose pseudotumor cerebri and CVST
  • Can distinguish traumatic tap vs. true hemorrhage.
• Xanthochromia:
  • Should be visible by 12 hr after onset of a SAH
  • Visual inspection is the most commonly used method – spectrometry (is more sensitive but has a high false-positive rate).

DIFFERENTIAL DIAGNOSIS

• Note: There can be significant overlap in these groupings.
• Acute single headache:
  • SAH
  • Meningitis
  • Vascular:
    • Acute intracerebral hemorrhage
    • Hypertensive encephalopathy
    • Cranial artery dissection
    • CVST
    • Cerebellar stroke
  • Ocular:
    • Acute narrow-angle glaucoma
    • Pituitary apoplexy
    • Temporal neuritis
  • Traumatic
  • Acute sinusitis
  • Toxic/metabolic:
    • Fever
    • Hypoglycemia
    • High-altitude disease
    • Carbon monoxide poisoning
  • Narcotic, alcohol, or benzodiazepine withdrawal
  • Post lumbar puncture
  • Cold stimulus headache
• Acute recurrent headache:
  • Presenting within days to weeks of onset
  • CVST
  • Pseudotumor cerebri
  • Temporal arteritis
  • SAH (rebleed)
  • Migraine, cluster, tension
  • Hypoxic
  • Trigeminal neuralgia
  • Postherpetic neuralgia
  • Coital and exertional headache
• Subacute headache:
  • Within weeks to months of onset
  • Chronic subdural hematoma
  • Brain tumor
  • Brain abscess
  • Chronic sinusitis
  • Temporomandibular joint syndrome
  • Chronic post-traumatic headache
  • Pseudotumor cerebri (idiopathic intracranial HTN)
  • Temporal arteritis
• Chronic headache:
  • Months to years since onset
  • Chronic tension headache
  • Analgesic abuse/rebound
  • Depression
  • Extracranial:
    • Trigeminal neuralgia: Transient, shock like facial pain
    • Temporal arteritis: Elderly, severe, scalp artery tenderness/swelling
    • Metabolic: Severe anemia
    • Acute glaucoma: Nausea, eye pain, conjunctival injection, increased IOP
    • Cervical: Spondylosis, trauma, arthritis

[Outline]

• SIGNS AND SYMPTOMS
• ESSENTIAL WORKUP
• DIAGNOSIS TESTS & INTERPRETATION
• DIFFERENTIAL DIAGNOSIS

INITIAL STABILIZATION/THERAPY

• ABCs if altered mental status
• Empiric antibiotics if bacterial meningitis is suspected, acyclovir if immunocompromised

ED TREATMENT/PROCEDURES

• Migraine (See Headache, Migraine)
• Tension:
  • Aspirin
  • Acetaminophen
  • NSAID
  • Nonpharmacologic (meditation, massage, biofeedback)
• Cluster (See Headache, Cluster)
• Temporal arteritis (See Giant Cell Arteritis)
• Intracranial infection (See Meningitis)
• Intracranial hemorrhage (See Subarachnoid Hemorrhage)

[Outline]

• INITIAL STABILIZATION/THERAPY
• ED TREATMENT/PROCEDURES

DISPOSITION

Admission Criteria

• Headache secondary to suspected organic disease
• Intractable vomiting and dehydration
• Pain refractory to outpatient management
• Consider ICU admission:
  • Suspected symptomatic aneurysm
  • Acute subdural hematoma
  • SAH
  • Stroke
  • Increased ICP
  • Intracranial infection

Discharge Criteria

• Most migraine, cluster, and tension headaches after pain relief
• Local or minor systemic infections (e.g., URI)

Issues for Referral

Patients with recurrent headaches should have follow-up with a neurologist or PCP.

MEDICATION

• Chlorpromazine: 25–50 mg IM/IV (peds: 0.5–1 mg/kg/dose IM/IV/PO) q4–6h
• Dexamethasone: 10–24 mg IV once
• Dihydroergotamine: 1 mg IM/IV, repeat q1h; max. dose 3 mg
• Ergotamine: 2 mg PO/SL at onset, then 1 mg PO q30min; max. dose 10 mg/wk
• Ketorolac: 30–60 mg IM; 15–30 mg IV once, then 15–30 mg q6h (peds: 1 mg/kg IV q6h)
• Lidocaine 4%: 1 mL intranasal on same side as symptoms
• Metoclopramide: 5–10 mg IM/IV/PO q6–8h
• Morphine: 2.5–20 mg (peds: 0.1–0.2 mg/kg/dose) IM/IV/SQ q2–6h
• Prochlorperazine: 5–10 mg IM/IM/PO TID–QID; max. 40 mg/d
• Sumatriptan: 6 mg SQ, repeat in 1 hr, up to 12 mg/24h

ALERT

[Outline]

• DISPOSITION
• MEDICATION

• The sensitivity for detecting SAH on CT scan falls rapidly after 24 hr. LP remains essential for all patients with suspected SAH presenting after 6 hr of symptom onset.
• Neurology consultation should not delay urgent imaging in patients with high-risk features.
• Use dopamine antagonists with caution in patients with QT prolongation or electrolyte abnormalities. Use ergotamines and triptans carefully in patients with a documented history of CAD.
• Patients with chronic headaches and multiple visits benefit from consistent protocols for pain management; however, be alert to significant changes in their symptoms
• Do not wait for LP results to empirically treat cases of suspected meningitis.

ICD9

• 339.00 Cluster headache syndrome, unspecified
• 346.90 Migraine, unspecified, without mention of intractable migraine without mention of status migrainosus
• 784.0 Headache

ICD10

• G43.909 Migraine, unsp, not intractable, without status migrainosus
• G44.009 Cluster headache syndrome, unspecified, not intractable
• R51 Headache

[Outline]

• ICD9
• ICD10

• Edlow JA, Caplan LR, O'Brien K, et al. Diagnosis of acute neurological emergencies in pregnant and post-partum women. Lancet Neurol. 2013;12:175–185.
• Perry JJ, Stiell IG, Sivilotti ML, et al. Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhage: Prospective cohort study. BMJ. 2011;343:d4277.
• Pope JV, Edlow JA. Avoiding misdiagnosis in patients with neurological emergencies. Emerg Med Int. 2012;2012:949275.
• Swadron, SP. Pitfalls in the management of headache in the emergency department. Emerg Med Clin North Am. 2010;28(1):127–147.

Josh W. Joseph