A patient with type 2 diabetes is taking a beta-blocker as part of treatment for hypertension. The nurse needs to monitor for which potential complication?

Choice A rationale Dehydration is not a primary complication directly associated with beta-blocker use. Beta-blockers, such as propranolol or metoprolol, primarily affect the cardiovascular system by blocking beta-adrenergic receptors, which decreases heart rate and blood pressure. Dehydration is typically caused by inadequate fluid intake or excessive fluid loss from conditions like vomiting, diarrhea, or diuresis. Choice B rationale Hyperkalemia is an elevated potassium level, which is a rare side effect of non-selective beta-blockers, but not a primary complication to monitor for in a patient taking a beta-blocker for hypertension. Hyperkalemia is more commonly associated with conditions like renal failure or the use of certain medications, such as ACE inhibitors or potassium-sparing diuretics. Choice C rationale Beta-blockers can mask the physiological signs of hypoglycemia in patients with diabetes, such as tremors, palpitations, and tachycardia. This occurs because the drugs block the sympathetic nervous system's compensatory response to low blood glucose, which normally involves the release of epinephrine. Consequently, a patient may not recognize a hypoglycemic event until it becomes severe. Choice D rationale Angina is a symptom of myocardial ischemia, and beta-blockers are often used to prevent it, not cause it. By reducing the heart rate and contractility, beta-blockers decrease myocardial oxygen demand. This effect helps to prevent chest pain associated with angina, making it a therapeutic benefit rather than a potential complication.