extensive radiographic findings. (b)Q fever is caused by Coxiella burnetii.
Infected individuals look ill, are diaphoretic, and febrile.(c)PCP is seen
almost exclusively in patients who are immunocompromised, such as
those with AIDS, malnourished, or on steroids. It is the most common
opportunistic infection seen in HIV patients. Patients typically present with
dyspnea, nonproductive cough, and fever. Chest radiograph may be nor-
mal in up to 20% to 30% of patients. The classic chest radiograph of PCP
demonstrates bilateral diffuse interstitial infiltrates in the perihilar region
and extending laterally in a “bat-wing” pattern. (e)The clinical hallmark of
ARDS is severe hypoxemia unresponsive to increased concentrations of
inspired oxygen. Many different conditions can precipitate ARDS; however,
gram-negative sepsis is the most common.
52.The answer is e.(Rosen, pp 938-956.)This patient is suffering from an
acute asthma attack. This is a reversible bronchospasm initiated by a variety
of environmental factors that produce a narrowing and inflammation of the
bronchial airways. The first-line treatment in order to open the airways
includes a β 2 - agonist,which acts to decrease bronchospasm of the smooth
muscle.
Corticosteroids (a)are an effective measure for decreasing the late
inflammatory changes involved in asthma. Magnesium sulfate (b)is also
thought to act in a similar manner, but should be initiated in refractory
cases of asthma. Epinephrine (c)decreases bronchospasm, but given its
clinical side effects should only be administered in patients deemed to be
in severe respiratory distress. Anticholinergics (d)are effective in patients
with COPD, and are also administered in combination with a β 2 -agonist to
patients with an acute asthma exacerbation. However, it should never be
given alone to treat asthma.
53.The answer is e.(Rosen, pp 1011-1052.)All patients with chest pain
and shortness of breath should receive an ECG.It is a quick, noninvasive
test that often provides substantive information. An ECG will show that
this patient is having a large anterolateral wall myocardial infraction (MI)
affecting much of her left ventricle, the reason for her heart murmur. An
ECG must be performed in those crucial first moments so that the proper
care can be delivered. This example reminds us of the importance of keep-
ing the differential diagnosis broad in patients that present with respiratory
distress. The other procedures may be done in a timely manner, but do not
necessarily need to be performed as the next most critical step.
66 Emergency Medicine