Which condition(s) would cause the nurse to hold a PRN order for magnesium hydroxide (Milk of Magnesia)?

Choice A reason:
Sucralfate does not primarily work by reducing acid production but rather by forming a protective barrier over ulcers. The statement "Sucralfate reduces acid production in the stomach" is incorrect. Sucralfate's main action is to adhere to the ulcer site and protect it, thus helping in the healing process. The student’s misunderstanding is that sucralfate reduces acid production, which is not the primary mechanism of action for this medication.

Choice B reason:
Sucralfate is known for having minimal systemic side effects because it works locally in the stomach rather than being absorbed into the bloodstream. The statement that sucralfate does not cause systemic side effects is correct, as sucralfate's action is mainly localized to the gastrointestinal tract, making systemic side effects uncommon.

Choice C reason:
Sucralfate should indeed be administered one hour before meals. This timing allows it to form a protective barrier on the stomach lining before food can stimulate acid production, which is crucial for its effectiveness in treating peptic ulcers. Therefore, the statement about its administration time is correct and does not indicate a need for further teaching.

Choice A reason:
Arterial emboli from a heart valve are not the most common cause of myocardial ischemia. While emboli can obstruct blood flow and cause ischemia, they are a less common cause compared to atherosclerosis. Embolic events typically result from conditions like atrial fibrillation or valvular heart disease but do not account for the majority of myocardial ischemia cases.

Choice B reason:
Atherosclerosis is the most common cause of myocardial ischemia. It involves the buildup of plaque within the coronary arteries, leading to reduced blood flow and oxygen supply to the heart muscle. This condition is a leading cause of coronary artery disease and is responsible for the majority of myocardial ischemia cases.

Choice C reason:
Idiopathic vasospasm, although a cause of myocardial ischemia, is not as common as atherosclerosis. Vasospasm refers to the sudden constriction of a coronary artery, which can reduce blood flow to the heart muscle. However, it accounts for a smaller percentage of ischemia cases compared to the widespread prevalence of atherosclerosis.

Choice D reason:
Venous emboli are typically associated with conditions such as deep vein thrombosis and pulmonary embolism, affecting the venous circulation rather than the coronary arteries. They do not commonly cause myocardial ischemia, which primarily involves the coronary arteries and arterial blockages.