In a patient with chronic obstructive pulmonary disease (COPD), which of the following interventions is most important?

Correct Answer: C

Rationale: Monitoring oxygen saturation is the most important intervention in a patient with COPD because it helps assess the adequacy of oxygenation. In COPD, patients often have compromised lung function, leading to decreased oxygen levels in the blood. Monitoring oxygen saturation allows healthcare providers to promptly identify and address any potential hypoxemia, which is vital in managing COPD exacerbations. While encouraging the patient to stop smoking (Choice A) is critical for long-term management, monitoring oxygen saturation takes precedence in the immediate care of a COPD patient. Administering bronchodilators (Choice B) and providing nutritional support (Choice D) are important aspects of managing COPD but are secondary to monitoring oxygen saturation, which directly impacts the patient's oxygenation status.

Correct Answer: A

Rationale: Helicobacter pylori infection is the most common cause of peptic ulcers. This bacterium can weaken the protective mucous coating of the stomach and duodenum, allowing acid to get through to the sensitive lining beneath. NSAID use (Choice B) can also cause peptic ulcers by disrupting the stomach's mucosal barrier. Excessive alcohol consumption (Choice C) and stress (Choice D) can exacerbate and contribute to ulcer formation but are not the primary cause.

Correct Answer: A

Rationale: Hyperkalemia is a common electrolyte imbalance in chronic kidney disease. In chronic kidney disease, the kidneys' reduced function leads to the decreased excretion of potassium, resulting in elevated serum potassium levels. This can be dangerous as hyperkalemia can lead to life-threatening arrhythmias. Hypokalemia (Choice B) is less common in chronic kidney disease as the impaired kidneys tend to retain potassium. Hypernatremia (Choice C) is more commonly seen in conditions such as dehydration, not primarily in chronic kidney disease. Hyponatremia (Choice D) is also possible in chronic kidney disease but is less common compared to hyperkalemia.

Correct Answer: A

Rationale: The correct answer is A: Chest pain. Chest pain is a hallmark symptom of myocardial infarction (MI) due to inadequate blood flow to the heart muscle. This pain can be severe, crushing, or squeezing, and may radiate to the left arm, jaw, or back. Shortness of breath (choice B), nausea (choice C), and fatigue (choice D) can accompany MI but are not as specific or characteristic as chest pain in diagnosing this condition. Therefore, chest pain is the primary symptom to recognize for suspected MI.

Correct Answer: A

Rationale: In chronic kidney disease, elevated creatinine levels are expected due to impaired kidney function. Creatinine is a waste product that is typically filtered out by the kidneys. With kidney disease, the clearance of creatinine is reduced, leading to its accumulation in the blood. Low hemoglobin levels (choice B) may be seen in chronic kidney disease due to decreased production of erythropoietin. However, elevated potassium levels (choice C) and low sodium levels (choice D) are more commonly associated with kidney dysfunction but are not as specific indicators of chronic kidney disease as elevated creatinine levels.