A 53-Year-Old Homeless Man Comes to the Emergency Department Due

question 924

Multiple Choice

A 53-year-old homeless man comes to the emergency department due to several days of shortness of breath and productive cough.  A month ago, the patient was evaluated for dysphagia and was found to have Candida esophagitis.  He received nystatin but refused any further workup and left against medical advice.  The patient uses cocaine and intravenous heroin.  Temperature is 38.8 C (101.8 F) , blood pressure is 121/72 mm Hg, pulse is 124/min and regular, and respirations are 22/min.  Oxygen saturation is 89% on 2 L/min of oxygen by nasal cannula.  He is awake, alert, and in mild respiratory distress.  There are extensive white plaques over the oral mucosa.  A 2/6 midsystolic murmur is heard at the left upper sternal border.  Lung auscultation is remarkable for faint, bilateral crackles.  There is no jugular venous distension or lower extremity edema.  Which of the following is the most likely underlying mechanism responsible for this patient's hypoxemia?

• A)Diffuse alveolar hypoventilation
• B)Increased pulmonary capillary wedge pressure
• C)Left-to-right intracardiac shunt
• D)Pulmonary hypertension
• E)Ventilation/perfusion mismatch

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Definitions:

Contact Precautions

Infection control practices used to prevent transmission of diseases that can be spread through direct or indirect contact with the patient or their environment.

Negative-Pressure Room

A specialized hospital room designed to contain airborne contaminants within the room, preventing their spread to other areas.

Hand Hygiene

The active engagement in practices like using hand antiseptic or soap and water to reduce the presence of pathogenic microorganisms on the hands.

Home Health Nurse

A home health nurse provides medical care, monitoring, and support to patients in their own homes, often as part of a broader home health care team.