Emergency Treatment of Headache

Introduction

Headache is the chief complaint in 2-3% of patients on admission to emergency departments (EDs) in the United States – the fourth most common reason for an ED visit. The incidence of headaches with significant morbid or fatal outcome is low. However, ruling out secondary causes of such headaches is essential. Once diagnosis is established, acute treatment measures and referral to appropriate specialists can be completed. Follow-up referral is crucial to avoid repeat ED visits and possible analgesic abuse. Repeat visits and obvious habituation problems will frustrate the staff of the ED and diminish the potential for recovery for the patient.

To adequately treat the patient presenting with the complaint of headache to the ED, the emergency physician should be aware of:

• Headache classification
• Appropriate diagnostic testing
• Available treatment modalities.

Headache classification is reviewed in the Classification section. The evaluating physician should be familiar with the dynamics of the headache history and the types of headache patients most likely to visit the ED. Although the emergency physician will rarely examine the patient for secondary causes of the headache, ruling out these possible morbid causes is imperative.

Of those headache patients visiting EDs, 4.5% to 20% will be experiencing some form of vascular headache. Tension-type headaches (TTH) are the most prevalent type of headache in patients presenting to the ED. Narcotic analgesics must be totally avoided in these chronic headache patients. Table 10-1 details the differential diagnosis of the types of headaches seen in the ED.

Headache history taking has been reviewed in the Diagnosis section. The interviewer in the ED has time constraints not experienced in a physician’s office setting. Obtaining an accurate history may be difficult if the patient is in acute distress, and involving a family member or friend may be necessary. In the ED setting, it is essential to determine:

• Onset of this particular episode
• Any triggering factors, particularly trauma
• Presence of associated symptoms
• Any prior history of similar headaches or family history of headaches
• Previous and current medications
• Previous tests and hospitalizations.

The physician should conduct a physical and neurologic examination, with the extent dependent upon the patient’s current status. During the examination, the physician should evaluate:

• Fundus
• Neck
• Throat
• Nose.

If the patient reports a recent onset of headaches or a change in the headache pattern, the physician should be alert to possible secondary causes. The presence of exertional aspects to the acute headache should also signify the need for extensive diagnostic testing.

A complete blood count is indicated if infection is suspected. If the test reveals a marked anemia, the physician should consider a hypoxia-related vascular headache. In those patients with status migrainosus (attacks lasting over 72 hours) associated with severe vomiting, serum electrolytes and renal function should be evaluated to treat complications of dehydration. Patients who are consuming excessive amounts of over-the-counter (OTC) or prescribed analgesics should undergo blood chemistries to determine renal or liver function. A sedimentation rate by the Westergren method should be performed on any patient over age 50 with recent-onset headache or a change in the headache pattern to rule out temporal arteritis. Prompt diagnosis and immediate treatment are essential to prevent irreversible blindness associated with this disorder.

Neuroimaging is an invaluable tool for the emergency physician confronted with headache patients. The criteria for ordering neuroimaging are listed in Table 10-2. Because of the acute presentations of headache that are seen in the ED, these more rigid guidelines are necessary. If the headache pattern suggests elevated intracranial pressure due to focal lesions, a computed tomography (CT) scan and careful eye ground examination are indicated prior to performing a lumbar puncture (LP) to prevent cerebellar herniation.

LP is indicated in those patients presenting with symptoms similar to:

• Subarachnoid hemorrhage (SAH)
• Meningitis.

LP can be used to determine the pressure of the cerebrospinal fluid (CSF), both when the needle first pierces the arachnoid mater (the opening pressure) and when it is retracted from the subarachoid space (the closing pressure). This makes it useful for diagnosing headaches due to altered cerebrospinal fluid (CSF) pressure, including:

• Headache attributed to idiopathic intracranial hypertension (IIH)
• Headache attributed to spontaneous intracranial hypotension (SIH).

Again, if a focal lesion is suspected, LP should not be undertaken until a CT scan has ruled out an intracranial lesion. Xanthochromia or red blood cells will be evident in the CSF of patients with SAH. In patients with meningitis, the CSF will reveal white blood cells as well as bacteria.

In the ED, the most striking presentation of headache will probably be patients with SAH. Usually, these patients will not provide a previous history of headaches. If they have a history of headaches, they will not have noticed a change in the headache pattern or difficulties with their treatment. However, they will describe:

• The worst headache ever
• Acute onset
• Nausea and vomiting
• Meningism
• Focal neurologic signs.

The associated symptoms are related to increased intracranial pressure. With the onset of bleeding, a transient loss of consciousness may be noted. The emergency physician should be aware that the “thunderclap” headache can occur in patients with migraine or SAH. A 50% mortality rate has been reported in patients with SAH, and 50% of those with SAH who survive the initial bleed but do not receive treatment will expire within the following 2 weeks. Immediate diagnosis will increase the survival rate for these patients.

Patients presenting to the ED with headache may have a disorder associated with changes in CSF pressure. Idiopathic intracranial hypertension is a type of increased CSF pressure-associated headache. It is most common among women of childbearing age. While this condition is generally rare (affecting 1-3 people per 100,000 persons), up to 40% of patients with IIH use ED services to for the headache. Symptoms are non-specific, including in addition to the headache:

• Visual darkening
• Pulsatile tinnitus
• Back pain
• Dizziness
• Neck pain
• Blurred vision
• Cognitive disturbance
• Radicular pain
• Diplopia.

The diagnosis of headache attributed to IIH can be challenging and is typically made after other possible causes are excluded; it is often diagnosed, especially among the most commonly affected population of childbearing age women. Lumbar puncture is used in the diagnostic process to determine the CSF pressure and composition; like for other increased CSF pressure headaches, a diagnosis of IIH headache requires a CSF pressure of >250 mm CSF (>280 mm CSF in children with obesity) and a normal CSF composition. Management depends on whether the IIH threatens the patients’ vision: if not, medical therapy for the headache is often sufficient; otherwise, surgery for CSF diversion or optic nerve sheath fenestration may be required. In the context of ED care, pharmacological pain relief and in some cases LP-based CSF drainage are often the only services that can be provided for patients with IIH-associated headache.

Patients may also present in the ED with headaches associated with low CSF pressure. These headaches pressure may be either spontaneous (headache attributed to SIH) or secondary to CSF leakage after an LP (post-dural puncture headache) or another procedure (CSF fistula headache). These headaches are typically orthostatic, ie, exacerbated by standing or sitting upright and ameliorated by lying down. Diagnosis of a low CSF pressure headache requires an LP-derived CSF pressure of <60 mm CSF or imaging evidence of a CSF leak. Like that attributed to IIH, headache attributed to SIH is often misdiagnosed; in addition to being orthostatic, SIH-associated headaches are typically accompanied by neck stiffness and hearing changes. Conservative management options include bed rest (remaining in a horizontal position), oral hydration and caffeine (intravenous or oral). In the ED context, pain management medication may be provided, or, in some cases, an autologous epidural blood patch – the injection of autologous blood to the region of the leakage – may be provided to seal the dural tear. Sealing the dural damage represents the definitive treatment for nearly all cases of low CSF pressure headache.

In dealing with meningitis, the emergency physician should be aware that this disorder can affect any population and is not limited to any particular season. These patients will more likely present to an ED as opposed to the primary care physician’s office. The clinical picture of meningitis includes:

• Severe global headache, throbbing in nature
• Nausea and vomiting
• Fever
• Photophobia
• Stiff neck
• An alteration in consciousness (in some patients)
• Rash.

The age of the patient can aid in determining the causative agent for the meningitis:

• Haemophilus influenzae—ages 2 through 5
• Neisseria meningitidis—older children and adolescents
• Streptococcus pneumonia—adults.

Immunosuppressive therapy renders patients especially susceptible to these and other organisms. Immediate, aggressive antibiotic therapy is essential to prevent a morbid outcome.

Headache due to brain tumor has been reviewed in Secondary Headaches Due to Organic Causes. These patients will rarely visit an ED since these slow, progressive headaches will usually respond to OTC analgesics and ice packs. Recent changes in headache pattern may alert the emergency physician to possible organic causes. Certain increases in intracranial pressure may exacerbate the headache, such as:

• Valsalva maneuver
• Exertion.

If the headache is accompanied by focal neurologic signs, neuroimaging is indicated. These symptoms may also validate the need for neurosurgical consultation.

Headaches associated with brain abscess have also been described in Secondary Headache Due to Organic Causes. The emergency physician should question the patient regarding:

• Recent-onset headache
• Recent or concomitant ear infection
• Recent history of sinusitis.

The pain will usually be apparent in the nasal and aural structures adjacent to the site of the infection. Brain abscess may manifest as:

• Headache
• Papilledema
• Other signs of localized traction and generalized displacement of the brain.

Brain abscess-associated signs include:

• Fever
• Leukocytosis
• Pleocytosis.

Certain generalities can be made regarding the site of the infection:

• Ear infection will usually produce abscesses above or below the tentorium
• Abscesses below the tentorium may cause hiccupping, vomiting and occipital headache
• Epidural abscess due to a sinus infection will produce pain in the frontal region adjacent to the diseased frontal, ethmoid and sphenoid sinus.

An elevated blood count, in the presence of fever and purulent nasal drainage, suggests the need for CT scanning and possible sinus X-rays. Prompt antibiotic therapy should be initiated and referral to the appropriate specialist is indicated.

A simple rule for all physicians treating patients with headache is to obtain a sedimentation rate by the Westergren method on all patients over age 50 with recent-onset headache. As discussed in, Headaches Due to Organic Causes, early diagnosis and aggressive steroid therapy are essential in patients with temporal arteritis to prevent the irreversible blindness associated with this disorder.

Emergency physicians may also encounter patients with hypertensive headache. Diagnosis is confirmed by:

• Diastolic pressure ≥110 mm Hg
• Headaches are worse in the morning and gradually decrease during the day
• Typically bilateral, although they can occur occipitally or involve the entire head
• Throbbing or “bursting” in nature
• Very severe
• Symptoms of catecholamine release, such as tremors or palpitations, may occur.

This type of headache may be a manifestation of another disorder, such as acute nephritis and acute pressor reactions. Referral for follow-up is essential after the blood pressure has been controlled and palliative measures for the headache are employed.

The diagnosis and treatment of migraine are described in detail in, Migraine Headaches. It should be reiterated that an adequate history and physical examination can facilitate distinguishing migraine from a possibly morbid medical emergency. Treatment in the ED is focused on abortive therapy and possible pain-relieving measures.

For the abortive treatment of migraine, several options are available in the ED. Intramuscular (IM) or intravenous (IV) dihydroergotamine (DHE) can be utilized. Subcutaneous sumatriptan is at least as effective as DHE and can also be considered, provided the patient has not used an ergotamine preparation prior to visiting the ED. The emergency physician may also consider prescribing the inhalation preparations of either DHE or sumatriptan. These agents are described fully in, Migraine Headaches. The phenothiazines may also be used in the ED for migraine abortive therapy. Metoclopramide demonstrated efficacy when used as single-agent therapy for migraine in an ED setting. Table 10-3 presents a protocol for emergency treatment of migraine.

Regarding pain relief, IM injection of ketorolac 60 mg or diclofenac 75 mg may provide rapid relief in contrast to other nonsteroidal anti-inflammatory drugs. Transnasal administration of butorphanol may be preferred to the use of injectable narcotic analgesics.

The patient with status migrainosus, i.e., a migraine attack lasting >72 hours, may come to the ED to terminate the attack. The protocol designed by Raskin and Raskin involved IV administration of DHE 0.5 mg in combination with metoclopramide 10 mg in repetitive doses every 8 hours for 2 days. To combat the sterile inflammation believed responsible for status migrainosus, the use of the corticosteroids, (eg, 4-10 mg by IV followed by another 4 mg every 6 hours as necessary) has been successful. Intramuscular administration of a long-acting preparation, such as methylprednisone 80 mg IM, may be utilized in the ED.

The short duration of a typical cluster attack precludes frequent visits to the ED while these patients are in a cluster series. By the time the patient arrives at the ED, the acute headache may have abated. Occasionally, the emergency physician may treat a patient with acute cluster headaches. The treatment of choice is oxygen inhalation by mask, at 7-12 L/minute for 10 to 15 minutes. Ergotamine preparations and other abortive measures are discussed in, Trigeminal Autonomic Cephalalgias.

In the ED, the patient with chronic headaches, either chronic TTH or coexisting migraine and TTH, may cause frustration for the staff and distrust toward the patient. It is essential that these patients be encouraged to seek follow-up care to prevent habitual ED visits as well as dependency on analgesics. Despite a busy ED, the physician must provide adequate time for evaluation of these patients to:

• Establish diagnosis
• Select nonhabituating analgesics
• Refer to appropriate specialists for follow-up care.

Treating headache in the ED can be a difficult, unrewarding task. The staff may have a basic mistrust of the patient’s motivation for seeking care. Unfortunately, there are patients who are drug-seeking and will make frequent ED visits to obtain habituating analgesics. In a busy ED, iatrogenic drug abuse is a danger since the overburdened staff will provide an analgesic, usually a narcotic, to free up the bed for a critically ill patient. Three measures must be employed in the ED for patients with chronic headache:

• Establish the diagnosis
• Provide immediate, palliative measures
• Provide referrals for follow-up care.

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