Correct Answer: A

Rationale: Abdominal swelling is a classic presentation and often the first noticeable sign of a Wilms tumor. This occurs due to the tumor mass in the kidney, leading to abdominal distension. Weight gain (Choice B) is less likely as a presenting symptom compared to abdominal swelling. Hypotension (Choice C) is not typically associated with a Wilms tumor unless complications like bleeding or shock occur. Increased urinary output (Choice D) is not a typical finding for Wilms tumor; instead, patients may present with hematuria or urinary symptoms.

Correct Answer: B

Rationale: Childhood obesity is a prevalent issue in children with Down syndrome due to factors such as decreased physical activity, slower metabolism, and potential overeating tendencies. Addressing obesity is crucial to promoting healthy lifestyles and preventing associated health complications. Rickets, a condition caused by a deficiency of vitamin D, is not commonly associated with Down syndrome. While anemia can occur in individuals with Down syndrome, obesity is a more common concern. Rumination, the regurgitation of food without nausea, is not a typical nutritional problem in children with Down syndrome.

Correct Answer: C

Rationale: The correct answer is C: Right ventricular hypertrophy, ventricular septal defect, pulmonic stenosis, and overriding aorta are the cardiac defects associated with Tetralogy of Fallot. In Tetralogy of Fallot, these specific abnormalities contribute to the classic features of the condition. Choice A is incorrect as it includes mitral valve stenosis, which is not typically part of Tetralogy of Fallot. Choice B describes transposition of the great arteries, not Tetralogy of Fallot. Choice D mentions an altered connection between the pulmonary artery and the aorta, which is not a defining characteristic of Tetralogy of Fallot.

Correct Answer: B

Rationale: Chest tubes are necessary after open-heart surgery to facilitate the drainage of air and fluid from the chest cavity. These tubes help prevent complications such as pneumothorax (accumulation of air in the pleural space) or cardiac tamponade (build-up of fluid in the pericardial sac), which can be serious postoperative issues. Options A, C, and D are incorrect because chest tubes are primarily used for draining purposes and not for increasing tidal volumes, maintaining positive intrapleural pressure, or regulating pressure on the pericardium and chest wall.

Correct Answer: A

Rationale: The primary goal of therapy during the acute phase of Kawasaki disease is to prevent coronary artery aneurysms, which are a serious complication of this condition. Coronary artery aneurysms can lead to long-term cardiovascular issues, making prevention crucial. While reducing fever and improving cardiac function are important aspects of managing Kawasaki disease, the primary focus in the acute phase is on preventing coronary artery aneurysms. Dehydration prevention is also essential but not the primary goal during the acute phase of this disease.