Poisoning and Overdose Answers 251(e)Heroin intoxication can cause respiratory depression. Patients usually
present with miotic pupils.
219.The answer is d.(Goldfrank et al, pp 1478-1486.)The most useful
diagnostic test obtainable in a suspected CO poisoningis a COHb level.
Normal levels range from 0% to 5%, as CO is a natural by-product of the
metabolism of porphyrins. COHb levels average 6% in one-pack-per-day
smokers. CO poisoning should be suspected when multiple patients, usu-
ally in the same family, present with flu-like symptoms, and were exposed
to products of combustion (eg, home heaters/generators). This most com-
monly occurs in colder, winter months. The mainstay of treatment is the deliv-
ery of oxygen. Hyperbaric oxygen is usually used for patients with COHb levels
greater than 25%.
(a)Lead toxicity is mainly a disease of children resulting from ingestion
of lead-based paints. Adults can be exposed to lead in a variety of occupa-
tional circumstances, such as welders, glassmakers, and scrap metal workers.
There is no classic presentation of lead toxicity. Therefore, high suspicion and
a thorough history are critical. The diagnosis is made by an elevated whole
blood lead level. (b)CO poisoning is often confused for a viral syndrome.
Patients with influenza usually present to the ED with high fever. (c)Malin-
gering is the intentional production of false or exaggerated symptoms moti-
vated by external incentives. (e)A lumbar puncture is used to diagnose
meningitis, which may present with headache, nausea, and fatigue.
220.The answer is e.(Rosen, pp 2069-2074.)Acetaminophen is one of the
most commonly used analgesic-antipyretic medications and causes more hos-
pitalizations after overdose than by any other pharmaceutical agent. Risk of
hepatotoxicity is best established by plotting the acetaminophen concentration
on the acetaminophen nomogram. Acetaminophen concentration must be mea-
sured between 4 and 24 hours after ingestion and then plotted on the nomo-
gram. Patients with acetaminophen concentrations on or above the treatment
line should be treated. This patient has a 4-hour serum acetaminophen concen-
tration of 350 μg/mL. According to the nomogram, at 4 hours any concentration
above 200 μg/mL should be treated. Therefore, the patient should be started
on NACandadmitted to the hospital.During her admission, she should be
evaluated by a psychiatrist regarding her attempted suicide.
The patient is at risk for acetaminophen toxicity and meets criteria for
treatment with NAC. Without treatment with NAC, she is at risk of devel-
oping liver failure and possible death. The patient is in first phase of an