Poisoning and Overdose Answers 263sedation.(e)α-Receptor blockade causes vasodilation and hypotension
leading to a decrease in systemic vascular resistance and widened pulse
pressure.
241.The answer is a.(Rosen, pp 2159-2162.)Hydrocarbons (HC)are a
diverse group of organic compounds that contain hydrogen and carbon.
Some common products containing HCs are household polishes, glues,
paint remover, and industrial solvents. Acute HC toxicity usually affects
three main target organs: the lungs, CNS, and heart. The lungs are most
commonly affected by aspiration of ingested HCs. Pulmonary toxicity is
associated with cough, crackles, bronchospasm, pulmonary edema, and
pneumonitis on chest radiograph. Certain HCs (eg, toluene, benzene,
gasoline, butane, chlorinated HCs) can have sedative/opioid-like effect and
cause euphoria, disinhibition, confusion, and obtundation. HCs can also
causesudden cardiac death,particularly after sudden physical activity
after intentional inhalation. It is thought that the HCs produce myocardial
sensitizationof endogenous and exogenous catecholamines, which pre-
cipitates ventricular dysrhythmias and myocardial dysfunction. One scenario
is the solvent-abusing person. EMS workers often describe an individual who
has used inhaled solvents, performed some type of physical activity, and then
suddenly collapsed.
In the scenario above, the patient inhaling butanewas approached by
a police officer and tried to run away. This sudden exertion most likely led
to a cardiac dysrhythmia. Paraphernalia is often found at the scene, includ-
ing plastic bags used for “bagging” (pouring HCs in a bag, then deeply
inhaling) or a HC-soaked cloth used for “huffing” (inhaling through a sat-
urated cloth). Other paraphernalia include gasoline containers, multiple
butane lighters, and spray paint cans.
(b)Ethanol intoxication typically does not lead to ventricular fibrilla-
tion.(c)In patients with heroin overdose who become hypoxic, ventricu-
lar fibrillation is possible. However, in this scenario the patient’s mental
status did not change in response to naloxone, the reversal agent for opi-
oids.(d)Cocaine intoxication may lead to ventricular fibrillation due to its
cardiac affects; however, this scenario is more consistent with hyrdocarbon
abuse.(e)PCP generally does not lead to cardiac dysrhythmias.
242.The answer is e.(Goldfrank et al, pp 741-753. Rosen, pp 2108-2110.)
β-Adrenergic receptor blockers(eg, Metoprolol) are commonly prescribed
medications for hypertension. β-Adrenergic antagonist overdose is often