Correct Answer: A

Rationale: The most important nursing intervention for a child with leukemia receiving chemotherapy is to monitor for signs of infection. Chemotherapy suppresses the immune system, putting the child at a higher risk of developing infections. Early detection and prompt treatment of infections are crucial to prevent complications and improve outcomes. Monitoring for signs of bleeding (choice B), dehydration (choice C), and pain (choice D) are also important aspects of care, but in this scenario, the priority is to prevent and manage infections due to the compromised immune system.

Correct Answer: B

Rationale: When an adolescent with type 1 diabetes experiences an insulin reaction, it is essential to quickly raise their blood sugar levels. Buying a soda and a hamburger to eat is the best choice in this situation as it provides a fast-acting source of sugar to counteract hypoglycemia. Calling parents immediately may cause a delay in receiving appropriate treatment. Administering insulin would further lower blood sugar levels, worsening the situation. Leaving the arena and resting would not address the immediate need to raise blood sugar levels.

Correct Answer: B

Rationale: During a vaso-occlusive crisis in sickle cell anemia, the priority nursing intervention is administering pain medication. Pain management is crucial to alleviate the intense pain experienced by the child. While administering oxygen can help improve oxygenation, it is not the most critical intervention during a vaso-occlusive crisis. Monitoring fluid intake is important for overall care but is not the immediate priority during a crisis. Encouraging physical activity is contraindicated during a vaso-occlusive crisis as it can worsen the pain and the crisis itself.

Correct Answer: B

Rationale: The correct answer is B: Tissue oxygen needs. Polycythemia occurs in response to chronic hypoxia, leading the body to increase red blood cell production to enhance oxygen delivery. In tetralogy of Fallot, a congenital heart defect that results in reduced oxygen levels in the blood, the body compensates by producing more red blood cells. Choice A is incorrect as low tissue oxygen needs would not trigger polycythemia. Choice C, diminished iron levels, is not the cause of polycythemia in this case. Choice D, hypertrophic cardiac muscle, is unrelated to the pathophysiology of polycythemia in tetralogy of Fallot.

Correct Answer: C

Rationale: Low-set ears with lobe creases are often associated with genetic disorders and can indicate underlying chromosomal abnormalities. This physical characteristic is known to be a common sign in various syndromes like Down syndrome. Choices A, B, and D are not directly linked to genetic disorders. Feeding problems and specific weight/height measurements are more general indicators of growth and development, while the ability to hop on one foot but not skip is a developmental milestone assessment that does not specifically point towards a genetic disorder.