International Headache Society (IHS) code and diagnosis: 1.5.2 Status migrainosus (9)

World Health Organization (WHO) code and diagnosis: G43.2 Status migrainosus

Short description (International Classification of Headache Disorder, Second Edition, 2004): A debilitating migraine attack lasting for more than 72 hours

A. Present attack in a patient with migraine without aura is typical with previous attacks except for duration.

B. Headache has the following features:

1. Unremitting for >72 hours

2. Severe intensity

C. Not attributable to another disorder

A headache that is equally debilitating but lasting somewhat <72 hours may require the same considerations and treatment as reviewed here. Headaches that are nondebilitating but otherwise meet the criteria for status migrainosus may be coded as 1.6.1 Probable migraine without aura.

Migraine is a complex syndrome with symptoms in five domains (2): pain, general irritability (photophobia, phonophobia, kinesophobia, osmophobia), gastrointestinal (GI) (nausea, vomiting, diarrhea), neurologic (cortical and brain stem), and mood (psychiatric, irritability, depression, or occasionally euphoria). In SM, pain, general irritability, and GI symptoms predominate. Whether these lead to mood changes or whether short temper and depression are part of the migraine process is unclear. SM typically resembles the subject’s usual severe migraine but there may be a spread of pain to other areas as the headache persists and the spread of allodynia or “secondary windup” occurs (1). The process appears to become a self-regenerating one as the patient has periods of some improvement and then worsening. The GI symptoms may become very severe. Persisting vomiting and diarrhea may lead to electrolyte imbalance, dehydration, hypotension, and even shock. Listlessness and easy fatigue may be very prominent.

Typically, photophobia, phonophobia, and kinesophobia are severe. As the headache persists the patient usually becomes increasingly irritable and the tolerance to pain diminishes. If allodynia occurs the pain continues to increase.

The differential diagnosis is that of migraine syndrome, which is reviewed in Chapter 45 by Swanson and Sakai. The most pressing entities to rule out are reviewed in Table 63-1. Unless severely dehydrated or in shock, the SM subject will have a normal neurologic examination (or no new neurologic findings) and normal mental status. Imaging by computed tomography or magnetic resonance imaging is in order if there are new neurologic findings.

In the first report on SM (4), emotional stress, depression, medication abuse, anxiety, diet, and hormones were noted to be major triggering or adjunctive factors. Psychiatric factors of depression and anxiety continue to be major contributors producing stress, sleep loss, fatigue, and increased susceptibility to migraine. Depression is frequently seen and the patient should be carefully evaluated for this problem (4,14).

In women, hormonal status needs to be assessed. The premenstrual or perimenstrual part of the female cycle is a time of particular risk for SM. The patient should also be assessed for recent infection such as “flu syndrome,” upper respiratory infection, or urinary tract infection, as these may trigger SM.

The relation of analgesic overuse or rebound-with-drawal-type headache (RWHA) adds another degree of complexity. In two studies of SM subjects, 61 to 78% had RWHA (3,17).

The subject with RWHA uses increasing amounts of symptomatic medication, but with decreasing relief from each dose. At some point in the cycle, not taking medication can trigger SM. The longer the subject has been in the RWHA cycle, the more likely SM precipitation occurs on sudden withdrawal. This is clearly a different mechanism from other varieties of SM.

Status migrainosus by definition is a severe migraine that has continued for greater than 72 hours and has been refractory to usual therapies for migraine (4). Correct diagnosis is essential, and the entities outlined in Table 63-1 masquerading as SM must be ruled out. Adjunctive or precipitating factors of SM must be sought. Hormonal factors, pre- or perimenstrual status, pregnancy, miscarriage, postpartum state, recent change in birth control pills, or hormone therapy are often factors. Psychiatric aspects such as depression, anxiety, and stress due to family or business affairs may be very important. Finally, the presence of RWHA is very important.

Treatment for this condition involves: (1) medication for the headache, (2) correction of any metabolic abnormalities such as dehydration, (3) management of nausea and vomiting and, at times, diarrhea, (4) management of the general irritability, (5) management of the psychiatric aspects, and (6) recognition of hormonal aspects (4,14,17). Because the patient has had a refractory headache for greater than 72 hours and has usually had multiple therapeutic measures, hospitalization for a short period is often appropriate.