Correct Answer: D

Rationale: A platelet count of 25,000/microliter indicates severe thrombocytopenia, which increases the risk of bleeding. It is crucial to initiate bleeding precautions, including regularly checking for signs of bleeding such as examining urine and stool for blood. Monitoring for fever every 4 hours (Choice A) should be included for neutropenic precautions, not specifically related to platelet count. Requiring visitors to wear respiratory masks and protective clothing (Choice B) is more relevant for patients with airborne precautions. Considering transfusion of packed red blood cells (Choice C) is not indicated for low platelet count but is more appropriate for managing anemia or low hemoglobin levels.

Correct Answer: A

Rationale: Naproxen sodium is a nonsteroidal anti-inflammatory drug that can cause inflammation of the upper GI tract. For this reason, it is contraindicated in a patient with gastritis. Gastritis involves inflammation of the stomach lining, and medications like Naproxen can exacerbate this condition. Calcium carbonate is an antacid that can help neutralize stomach acid and may actually provide relief for gastritis symptoms. Clarithromycin is an antibiotic used to treat H. pylori infection, a common cause of gastritis. Furosemide is a loop diuretic used to treat conditions like edema and hypertension, not directly contraindicated in gastritis.

Correct Answer: A

Rationale: Green vegetables and liver are rich sources of folic acid. Green vegetables like spinach, asparagus, and broccoli are high in folic acid content. Liver, especially from chicken or beef, is also a good source of folic acid. Yellow vegetables and red meat (choice B) do not contain as high a concentration of folic acid as green vegetables and liver. Carrots (choice C) are nutritious but do not have the highest concentration of folic acid. Milk (choice D) is not a significant source of folic acid compared to green vegetables and liver.

Correct Answer: B

Rationale: The correct answer is that the patient has a pacemaker. A pacemaker is a contraindication to MRI scanning due to the interference with the magnetic fields of the MRI scanner. This interference can potentially deactivate the pacemaker, putting the patient at risk. Patients with cardiac implantable electronic devices (CIED) are at risk for inappropriate device therapy, device heating/movement, and arrhythmia during MRI. This necessitates special precautions such as scheduling in a CIED blocked slot or having electrophysiology nurse or technician support. It is important to ensure that the patient's pacemaker is MRI conditional before proceeding with the scan. The other choices, such as being allergic to shellfish, suffering from claustrophobia, or taking antipsychotic medication, are not direct contraindications to undergoing an MRI scan for suspected lung cancer.

Correct Answer: C

Rationale: In acute ketoacidosis, a patient typically experiences rapid weight loss due to the body burning fat and muscle for energy in the absence of sufficient insulin. Therefore, weight gain would not be expected. Vomiting may occur due to the metabolic disturbances associated with ketoacidosis. Extreme thirst is a common symptom as the body tries to compensate for dehydration. Acetone breath smell is a classic sign of ketoacidosis as acetone is one of the ketones produced during this condition.