ACTIONABLE HEADACHES

Headache is an almost universal symptom that occasionally has a serious or urgent cause. Headache, like chest pain and dizziness, is so common that all clinicians must have a routine for reliably identifying the minority that require emergency or urgent attention.

The sheer volume of patients with complaints of headache in a busy practice requires that clinicians quickly determine which headaches are merely unpleasant, while remaining vigilant for the occasional patient whose headache has an urgent or serious cause.

One in twenty people consult physicians about headaches in any one year ¹. The International Headache Society distinguishes 13 major categories of headache, and 129 subcategories ².

Up to 10% of all emergency room patients have headache as a symptom ³, and about 2% of emergency room visits are for a chief complaint of headache ⁴.

Nevertheless, only 1% of headaches in emergency room patients have serious or urgent cause ⁵, of which subarachnoid hemorrhage and meningitis ⁶ are by far the commonest. Indeed, misdiagnosis of these two conditions accounts for 2-5% of all claims filed against emergency room physicians ^{7, 8}.

Headache may or may not dominate the symptoms of meningitis and a common diagnostic problem in both adults and children is that headache often accompanies less serious infections. A further diagnostic difficulty is that meningitis may develop as a complication of throat infections.

SubArachnoid hemorrhage (SAH) is bleeding into the cerebrospinal fluid surrounding the brain, usually from "blow out" of an aneurysm (outpouching of an artery) just behind the eyes. Once the bleeding has occurred, most of the damage is done, and action for missed diagnosis often fails on Causation.

However, 50% of SAH patients have leakage of blood from the aneurysm, a sentinel bleed, days to months earlier ⁹. This "worst headache of my life" may be of "thunderclap" onset, and is often misdiagnosed. Urgent investigation includes both Computed Tomography(C-T) scanning and spinal tap. Cerebral arteriography (dye-enhanced imaging studies of the arteries supplying the brain) is followed by emergency neurosurgery to place a surgical clip on the aneurysm.

In the elderly, temporal arteritis (= giant-cell arteritis) causes a new-onset headache located in the temple. Erythrocyte Sedimentation Rate (ESR) is usually significantly increased, and temporal artery biopsy may be diagnostic, though both tests can be normal ¹⁰. There is urgency to administer corticosteroid medication, to prevent potential sudden blindness.

Certain features of headache alert the careful physician to make or exclude a serious diagnosis. These qualities¹⁰ of headache should alert the busy clinician to the need for a complete evaluation.

Particular elements of physical examination distinguish substandard misdiagnosis from simple error. Claims of substandard assessment may succeed if delayed diagnosis or misdiagnosis occurred and important components of the clinical examination ¹¹ are not documented.

Not all these elements of the physical examination need be present in every case. However, if the defence claims misdiagnosis occurred despite standard assessment, relevant items should have been documented.

Copyright © 2009 Electronic Handbook of Legal Medicine