Which of the following is a long-acting insulin used to control blood sugar levels?

Choice A rationale

D5W (dextrose 5% in water) is an isotonic solution in the bag but becomes hypotonic in the body as dextrose is metabolized, leading to free water redistribution. This fluid is not ideal for dehydration as it does not contain electrolytes and can potentially dilute existing electrolytes, which is counterproductive for replacing lost volume and salts.

Choice B rationale

0.9% normal saline is an isotonic solution, meaning it has a similar concentration of solutes to the body's plasma. It is the most appropriate choice for treating dehydration, as it replenishes both fluid volume and sodium chloride, which are commonly lost during dehydration, effectively expanding the intravascular compartment without causing major fluid shifts.

Choice C rationale

0.45% saline, or half-normal saline, is a hypotonic solution with half the sodium concentration of normal saline. This fluid is used to replace free water deficits and for hypernatremia, but it is not the first-line choice for general dehydration as it does not effectively expand the intravascular volume and can cause fluid shifts into cells.

Choice D rationale

Packed red blood cells (PRBCs) are blood products used for anemia or significant blood loss to increase oxygen-carrying capacity. They are not a fluid replacement for dehydration. Administering blood when it's not clinically indicated for fluid volume deficit is inappropriate and carries risks of transfusion reactions and fluid overload.

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.