Correct Answer: C

Rationale: The correct answer is C: cobalamin (vitamin B12). Methotrexate can lead to a deficiency in cobalamin, resulting in megaloblastic anemia. Therefore, increasing the oral intake of cobalamin is essential to address this deficiency. Choice A, iron, is incorrect because megaloblastic anemia caused by methotrexate is not typically due to iron deficiency. Choice B, folic acid, is also incorrect as methotrexate does not directly cause folic acid deficiency. Choice D, ascorbic acid (vitamin C), is incorrect as it is not directly related to megaloblastic anemia caused by methotrexate; instead, cobalamin is the key vitamin that needs attention.

Correct Answer: B

Rationale: The correct answer is to evaluate the effectiveness of opioid analgesics. In sickle cell crisis, pain is the most common symptom and is usually managed with large doses of continuous opioids. Monitoring fluid intake (Choice A) is important, but limiting fluids may not be necessary. Encouraging ambulation (Choice C) is generally good but may not be the priority during a sickle cell crisis. Educating the patient about nutrition (Choice D) is important for overall health but may not be the immediate focus during a crisis.

Correct Answer: C

Rationale: The correct answer is C: 'Do you take medication containing salicylates?' Petechiae are tiny, pinpoint, red or purple spots on the skin due to bleeding under the skin. Salicylates, which are found in medications like aspirin, interfere with platelet function and can lead to petechiae and ecchymoses. Asking about salicylate-containing medications is crucial in this situation. Choices A, B, and D are incorrect because they are not directly related to the development of petechiae.

Correct Answer: D

Rationale: A low white blood cell (WBC) count in an older patient is concerning as it indicates a potential compromise in the patient's immune function. White blood cells are crucial for fighting infections and a low count could lead to an increased risk of infections. Hematocrit, hemoglobin, and platelet count are important parameters to assess, but a low WBC count takes priority in this case due to its direct impact on immune health.

Correct Answer: D

Rationale: The correct answer is D: 'Wash hands regularly and avoid individuals who are ill.' After a splenectomy, the patient is at an increased risk of infection, particularly from gram-positive bacteria. Proper hand hygiene and avoiding contact with sick individuals are crucial to prevent infections. Choices A, B, and C are incorrect because checking for swollen lymph nodes, watching for excessive bleeding or bruising, and taking iron supplements are not specifically related to the increased infection risk post-splenectomy.