What is the most important intervention for a patient with allergic rhinitis?

Correct Answer: B

Rationale: The most important intervention is to assist the patient in identifying and avoiding potential allergens. Intranasal corticosteroids (not oral antihistamines) should be started several weeks before the allergy season.

Correct Answer: A

Rationale: Cor pulmonale is right ventricular failure caused by pulmonary hypertension, so clinical manifestations of right ventricular failure such as peripheral edema, jugular venous distention, and right upper-quadrant abdominal tenderness would be expected.

Correct Answer: D

Rationale: The patient's history and symptoms suggest possible tension pneumothorax, a medical emergency. The other patients also require assessment as soon as possible, but tension pneumothorax will require immediate treatment to avoid death from inadequate cardiac output or hypoxemia.

Correct Answer: C

Rationale: Spirometry will help establish the COPD diagnosis. Bronchodilators should be avoided at least 6 hours before the test.

Correct Answer: C

Rationale: Manganese (IV) oxide is widely used as a catalyst to accelerate the decomposition of hydrogen peroxide into oxygen gas.