Convincing the skeptic. How to fix emergency department headache management

In their analysis of a research database from an academic emergency department (ED) in California (1), Drs McCarthy and Cowan identify three features of emergency headache care that have been reported by multiple clinical investigators from a multitude of North American EDs (2–7): (i) emergency physicians often fail to assign specific primary headache diagnoses to their headache patients; (ii) emergency physicians frequently treat migraine in particular and headaches in general with opioids; (iii) emergency physicians use triptans infrequently and dihydroergotamine rarely.

These practices seem difficult to understand. In the outpatient setting, an accurate headache diagnosis will lead to appropriate treatment. Parenteral opioid use has been associated with undesirable headache outcomes, such as headache recurrence and ED recidivism (3). Long-term problems associated with recurrent use of opioids include refractoriness to standard headache medications (8) and chronification of migraine (9). Triptans and dihydroergotamine on the other hand are evidence-based therapies. The number needed to treat for subcutaneous sumatriptan, for example, is a very impressive ‘2’ (10).

Unfortunately, there are no data available to help us comprehend and contextualize emergency practice—why do emergency physicians practice as they do? It is clear that time has not changed long-held practice patterns—opioid use for management of migraine in the ED is as prevalent today as it was 15 years ago (4). As demonstrated by Drs McCarthy and Cowan and elsewhere (1,4), this practice is highly prevalent in academic settings, the setting in which one might most expect to see appropriate practice.

Use of opioids in the ED for migraine may be an education issue—it could be that emergency physicians simply do not appreciate the long-term sequelae of repeated opioid use. Alternatively, it may be an informed choice. Consider how a skeptic might respond to the American Headache Society’s Choosing Wisely guidelines (11): ‘Parenteral opioids are a guideline-supported, evidence-based therapy (12). There are no high quality clinical data demonstrating detrimental effects of parenteral opioids when compared to alternative therapy. Much of the data come from non-randomized studies, which failed to account for important baseline factors’. For example, Drs McCarthy and Cowan did indeed find an association between parenteral opioid use and length of stay. However, is this because of opioid administration, or are there plausible unmeasured confounders, such as the severity of the underlying headache disorder or duration of the acute attack? Could it be that the patients treated with parenteral non-steroidal anti-inflammatory drugs (NSAIDs) in Drs McCarthy and Cowan’s database were some of the many patients who present to the ED having not taken any medication at all, while the ones given opioids were the patients with chronic migraine and medication overuse headache who had already exceeded recommended doses of triptans and NSAIDs? Failure to account for these baseline differences is a limitation encountered in many retrospective ED analyses. There are compelling data demonstrating an association between outpatient oral opioids and progression of episodic to chronic migraine (9). However, it is not clear if these data are relevant to patients who receive a single dose of parenteral hydromorphone in the ED.

Consider the dilemma of the busy emergency physician when deciding among acute headache therapeutics; metoclopramide, droperidol and ketorolac each have FDA black box warnings. All the parenteral anti-dopaminergics can cause akathisia, which is often an unpleasant experience for the patient and, at least theoretically, may cause tardive dyskinesia. Subcutaneous sumatriptan causes adverse medication effects in more than 50% of patients when administered in the ED setting (13). While triptans are probably safe in pregnant or mildly hypertensive patients, unknown pregnancy status and high blood pressure certainly might give the emergency physician pause before administering one of these medications. Early pregnancy cannot be excluded by history alone. One-quarter of ED headache patients present with at least moderately elevated blood pressure (14). In our ED-based sumatriptan trials, we have excluded more than 25% of potential subjects for pregnancy and elevated cardiovascular risk. Finally, some patients may have recently taken large enough doses of triptans or NSAIDs that further administration of these agents would be both contraindicated and unlikely to succeed.

Now consider the appeal of opioids. Emergency physicians know this class of medication well. Opioids are quite potent, but are safe when administered in a monitored setting (15). Importantly, opioids can be administered in successive doses until a patient’s pain is controlled.

However, the reality of ED-based headache management is that, while opioids may be useful acutely, they are certainly overused. It is probably true that clinic-based physicians underestimate the difficulty of choosing an appropriate medication for an ED patient who presents for the first time to a particular emergency physician within the throes of an acute headache. On the other hand, emergency physicians no doubt underestimate the downstream consequences of opioids when used in patients with chronic recurrent pain disorders. Unfortunately, evidence-based answers are not yet available: it is not clear how many of the millions of patients who receive opioids for headache in North American EDs wind up in a headache clinic with chronic migraine and how many would have wound up in the same place even if they had been treated in the ED with a migraine-specific agent.

With regard to parenteral therapeutics for acute migraine, patients’ preferences are poorly understood. Do patients prefer metoclopramide or sumatriptan or ketorolac to hydromorphone? Would a patient rather face the risk of akathisia or the risk of a recurrent ED visit? What is needed, we believe, are randomized comparative effectiveness studies designed specifically to answer these questions. For now, interested headache specialists should collaborate with their ED colleagues. Together they should determine barriers to implementation of headache treatment protocols and jointly develop protocols that are pragmatic, feasible and beneficial to patients.

With regard to the issue of diagnosis in the acute care setting, we empathize with our colleagues’ non-specific coding. We understand that the majority of headaches that present to an ED ultimately prove to be migraine, but we also know that many acute headaches prove difficult to categorize because of atypical or conflicting features and prolonged duration of headache (7,16). However, regardless of whether the acute headache takes the form of migraine or tension-type headache, it is likely to respond to most non-opioid parenteral treatments, including subcutaneous sumatriptan (17), metoclopramide (18) and ketorolac (19). We do our best to provide our patients with a specific diagnosis, but because the vast majority of primary headaches in the ED take the form of migraine or tension-type headache (16), diagnosis is not necessary acutely. This in fact may be key advice to emergency physicians as interested parties meet to develop local parenteral treatment protocols for acute headache: You do not always need to arrive at a specific diagnosis. Once you have ruled out secondary headache, treat with these medications: ___. Caveats, of course, would be needed for cluster headache, paroxysmal hemicrania and other recurrent headaches that only uncommonly appear in the ED (16). While patients are often eager to receive a specific diagnosis that they can then research and reference, we know that ED interventions designed to educate headache patients produce very modest long-term benefits (20). The most important intervention emergency physicians can deliver for their headache patients is to connect them with outpatient physicians savvy about headache management, who will then provide these headache patients with appropriate acute therapeutics, initiate preventive therapy and counsel their patients against receiving opioids in the ED.