A patient with a history of chronic heart failure is admitted to the emergency department with severe dyspnea and a dry, hacking cough. Which action should the nurse do first?

Correct Answer: C

Rationale: This patient's severe dyspnea and cough indicate that acute decompensated heart failure (ADHF) is occurring. ADHF usually manifests as pulmonary edema, which should be detected and treated immediately to prevent ongoing hypoxemia and cardiac/respiratory arrest. The other assessments will provide useful data about the patient's volume status and also should be accomplished rapidly, but detection (and treatment) of pulmonary complications is the priority.

Correct Answer: C

Rationale: Endothelium and mesothelium are composed of simple squamous epithelium for efficient exchange and lining.

Correct Answer: B

Rationale: The 1st heart sound (S1) is caused by the closing of the atrioventricular (AV) valves at the start of systole.

Correct Answer: D

Rationale: The total delay in the AV node and bundle is about 0.13 seconds, allowing atrial contraction before ventricular.

Correct Answer: B

Rationale: In mitochondria, HMG CoA is used in ketogenesis to produce ketone bodies.