Correct Answer: C

Rationale: Weight is the most accurate indicator of fluid balance in pediatric patients. Changes in weight reflect shifts in body fluid levels more directly compared to other parameters. Blood pressure and heart rate may be affected by various factors other than fluid balance. While urine output is important in assessing renal function, it may not provide a comprehensive picture of overall fluid balance in pediatric patients.

Correct Answer: D

Rationale: The decision to advance feedings after a pyloromyotomy is based on the infant's ability to tolerate the current feedings without vomiting or abdominal distention. Ensuring the infant can keep down Pedialyte is the key indicator for moving to the next stage of feeding. Choices A, B, and C are incorrect because they do not directly relate to the infant's ability to tolerate the feeding. An infiltrated IV line, lack of voiding, or the mother's statement do not provide direct information on the infant's tolerance to the feeding, unlike the absence of vomiting and distention.

Correct Answer: B

Rationale: The correct answer is B: Encourage oral rehydration. Oral rehydration is the first-line treatment for moderate dehydration in children. It helps restore fluid balance and electrolyte levels. Administering IV fluids (Choice A) is usually reserved for severe cases of dehydration where oral rehydration is not feasible or ineffective. Monitoring vital signs (Choice C) is important but should not replace the immediate need for rehydration. Providing clear fluids (Choice D) may not contain the necessary electrolytes required for effective rehydration.

Correct Answer: A

Rationale: The correct answer is A. Cimetidine (Tagamet) is an H2 receptor antagonist that works by reducing gastric acid secretion. This action helps to decrease the acidity in the stomach, which in turn reduces the symptoms of gastroesophageal reflux. Choice B is incorrect because cimetidine does not neutralize acid but rather decreases its production. Choice C is incorrect as cimetidine does not affect the rate of gastric emptying time. Choice D is incorrect as cimetidine does not coat the lining of the stomach and esophagus but instead works to reduce gastric acid secretion.

Correct Answer: C

Rationale: The most important intervention in managing a child with sickle cell crisis is the administration of pain relief. During a sickle cell crisis, severe pain is a prominent symptom due to vaso-occlusive episodes. Effective pain management, along with adequate hydration and oxygen therapy, is crucial in treating a sickle cell crisis and preventing further complications. Choice A, the administration of iron supplements, is not the priority during a sickle cell crisis. Iron supplements are typically used to manage anemia in individuals with sickle cell disease but are not the primary intervention during a crisis. Choice B, the initiation of a high-calorie diet, is not the most critical intervention during a sickle cell crisis. While proper nutrition is important in managing sickle cell disease, it is not the immediate priority during a crisis. Choice D, limiting fluid intake, is not recommended during a sickle cell crisis. Hydration is essential in managing sickle cell crisis to prevent complications like dehydration and further vaso-occlusive episodes.