Headache Answers 369the edges accumulate edema from the increase pressure of the anterior cham-
ber. The cornea should not take up fluorescein. LP (d)is used to diagnose
intracranial pathology. The acute unilateral pain of glaucoma may make
the clinician consider a SAH, but glaucoma should always be considered.
A change in visual acuity (e)is nonspecific and should not be a diagnostic
for glaucoma.
341.The answer is b.(Kao, pp 985-1018.)The patients are experiencing
symptoms of carbon monoxide (CO) poisoning.CO is colorlessand
odorless.Patients often present with mild nonspecific symptoms includ-
ing headache, malaise, and fatigue. Severe toxicity manifests as neurologic
and cardiac toxicity. Severe cases may manifest as disseminated intravascular
coagulation, circulatory shock, multiorgan failure, ischemic cardiac disease,
renal failure, or noncardiogenic pulmonary edema. Although there is decreased
blood oxygen content, patients will not exhibit cyanosis as there is not enough
deoxyhemoglobin present to cause it. Common sources of CO include fossil
fuel—burning engines, fumes from coal- or gas-burning stoves, and smoke
from accidental fires. CO intoxication is more prevalent during the winter when
potentially faulty heating systems are in use or when patients attempt to sup-
plement their home heat using their oven. Initial therapy is aimed at increasing
arterial oxygen content by providing supplemental oxygen. Mild intoxication can
be managed with supplementary oxygen alone. Elevated carboxyhemoglobin
levels require treatment with hyperbaric oxygen.
Respiratory isolation (a)is indicated in cases of suspected bacterial menin-
gitis where N meningitidisis thought to be the causative organism. Antibiotics
and LP (c)are appropriate if you suspect meningitis. Triptans and antiemetics
(d)are first-line treatments for migraine headaches. Transfer to a hyperbaric
facility(e)is indicated for persistent altered mental status, loss of conscious-
ness, seizure, stroke, myocardial ischemia, or pregnancy with a documented
carboxyhemoglobin level greater than 15%.
342.The answer is a.(Evans, pp 237-249.)After head trauma, 30% to 90%
of patients complain of headache during their convalescence. Postconcussive
headachesare notable for their variabilityin frequency, location, and associ-
ated symptoms. They are often exacerbated by physical activity or changes in
position and may be clinically difficult to distinguish from other headache
syndromes. In patients with preexisting migraines, increased frequency of
their normal migraine syndrome is often noted. Most patients have resolution
of their headaches after 4 weeks. In 20% of patients, their postconcussive