Analgesia for the emergency headache patient

SCOPE OF THE PROBLEM Headaches present a frequent diagnostic and therapeutic challenge to emergency physicians. In fact, it is estimated that patients with the complaint of headache account for 1-2% of all emergency department (ED) visits. Primary headache, also known as “benign headache,” is a headache that is not “secondary” to some identified discrete pathology (e.g., meningitis, sinusitis, subarachnoid hemorrhage, toothache, etc.). The ED evaluation of headache is twofold: first, to determine whether the headache is primary (Table 15-1) or secondary (Table 15-2), and then, if primary, to relieve the patient’s pain, and if secondary, to treat the underlying condition. The International Headache Society (IHS) has established several definitions for classifications of primary headaches. Although these remain useful in determining long-term treatment strategies, most ED patients present with undifferentiated headaches. These include migraine, probable migraine, episodic tension type, and cluster headaches. For the practical purpose of ED evaluation, ED patients with headache may be classified as serious or benign after the initial evaluation. The benign causes of headache (primary headaches) have been reported to account for up to 90% of ambulatory patients presenting with a complaint of headache. Since the further differentiation of the headache before treatment is unlikely to occur in the ED setting, treatment strategies must take into account the full range of headache subtypes and the evolving nature of the diagnosis of a patient’s headache pain.