Shortness of Breath Answers 6754.The answer is c.(Rosen, pp 2119-2124.)The crystallized free base of
cocaine is known as “crack cocaine.” This form, smoked through a pipe,
produces a highly lipid-soluble vapor that allows for rapid transport from
the lungs to the brain for a quicker high compared to cocaine that is snorted
or injected. As a result of this mechanism, the substance can be concen-
trated in high amounts in the lung parenchyma causing an infiltrative
inflammatory processandpneumonitisreferred to as “crack lung.” This
can subsequently result in respiratory failure.
Cannabis(a)used in conjunction with inhaled β 2 -agonists may result
in bleb formation and subsequent pneumothorax, but not pneumonitis.
Opioids(b), methamphetamine (d), and alcohol (e)may have pulmonary
effects through secondary mechanisms, but are not primarily responsible
for this type of presentation.
55.The answer is b.(Rosen, pp 388-391, 1000-1005.)Inspiratory and
expiratory radiographsallow better visualization of the lung pleura and
may help better elucidate the presence of a pneumothorax not initially
visualized on the chest radiograph.
A repeat chest x-ray (a)may be performed; however it will be low-
yield if the original was performed correctly. A chest CT scan (c)may be
done, but after the proper films are performed. Chest thoracostomy (d)
involves placing a tube inside the pleural cavity to evacuate the intrapleural
air and may be performed if the patient continues to decompensate and if
the suspicion for a pneumothorax remains high. Chest thoracotomy (e)
involves opening the chest cavity and is reserved for the severest cases of
cardiovascular collapse.
56.The answer is c.(Rosen, pp 1005-1009.)Pleural effusions are most
easily detected on a lateral decubitus film with the affected side down,
which in this case is the left side. Accumulations of 5 to 50 mL of fluid can
be detected with this view.
Small effusions can be missed entirely on (a)supine views and are not
generally apparent on PA views (e)and lateral views (d)until 200 mL or
more of fluid are present.
57.The answer is d.(Rosen, pp 801-813.)Thesinged naresseen in this
patient should give you a clue to the possibility of severe thermal burns.
Although there is minimal external involvement, damage from the heat
may extend deep into the pulmonary system through inspiration. This results