CHAPTER 59 ■ PAIN: HEADACHE DENIS R PAUZé, CHRISTOPHER MALABANAN INTRODUCTION Headache is a common complaint of pediatric patients in the emergency department (ED) It is estimated that by the age of 15 years, up to 75% of children have experienced headaches, although most are cared for at home Headache as an isolated complaint is a relatively unusual presentation in pediatric patients; it is more often one of a number of symptoms, such as fever, lethargy, sore throat, neck pain, and vomiting Like other challenging presentations, headache is seen with regularity and is often benign, but in a small subset of patients, it can portend a potentially lifethreatening illness Therefore, the primary responsibility of the emergency physician is to make the important discrimination between “bad” headaches and benign headaches Fortunately, this differentiation can almost always be done successfully after a thorough history and physical examination, and when necessary, laboratory and radiographic tests One notable exception to this rule, however, is brain tumor Although most serious illnesses that cause headache (e.g., meningitis, encephalitis, ruptured vascular anomaly) will be readily classified in the “bad” category, the presence of a brain tumor may not be The history can be subtle, and the examination is commonly unrevealing, often leading to a delay in diagnosis Therefore, characteristics of headaches caused by a brain tumor are described in detail in this chapter Above all, the key to proper management of such patients is ensuring appropriate follow-up care PATHOPHYSIOLOGY For a headache to occur, there must be a noxious stimulus that affects one or more pain-sensitive structures Injury to an area that is insensitive to pain, such as nonhemorrhagic stroke, may cause significant morbidity but will not manifest as headache It is therefore useful to consider the sensory innervation of the head and neck All extracranial structures are sensitive to pain Thus, processes that affect the sinuses, oropharynx, scalp, or neck musculature often cause patients to complain of headache In contrast, certain intracranial structures are sensitive to pain and others are not For example, the brain, ependymal lining, choroid plexus, and much of the dura and pia-arachnoid over the hemispheres are insensitive to pain Pathologic processes affecting these areas can cause headache, but only by