A 45-Year-Old Man Comes to the Emergency Department Due to Severe

question 254

Multiple Choice

A 45-year-old man comes to the emergency department due to severe dyspnea and chest discomfort that began earlier in the day.  The dyspnea has been worsening throughout the day and has been present at rest.  He reports no inciting trauma.  The patient has no other medical conditions and takes no medications.  He has a 20-pack-year smoking history and does not use alcohol or illicit drugs.  Temperature is 36.7 C (98 F) , blood pressure is 110/60 mm Hg, and pulse is 96/min.  Arterial blood gas drawn on room air shows an arterial partial pressure of oxygen (PaO₂) of 54 mm Hg and an arterial partial pressure of carbon dioxide (PaCO₂) of 26 mm Hg.  Which of the following processes is most likely occurring in this patient?

• A)Alveolar hyperventilation
• B)Decreased chest wall compliance
• C)Expiratory air trapping
• D)Poor respiratory drive
• E)Respiratory muscle fatigue

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Definitions:

S-cam Actuated Brake Shoes

Part of a drum brake system where an S-shaped cam is used to push the brake shoes outwards against the drum to slow or stop the vehicle.

Pair

Two things that are designed or used together or considered in relation to each other, often matching or corresponding in form or function.

Trailer Service Brake Signal

An electrical or air signal from the towing vehicle to the trailer, activating the trailer's service brakes.

Tractor Protection Valve

A safety device in air brake systems on trucks and trailers, designed to preserve air pressure in the tractor’s brakes in the event of a trailer air supply failure.