Correct Answer: A

Rationale: An allergy to shellfish often indicates an allergy to iodine, which is used in contrast dyes for CT scans. This poses a significant risk of an allergic reaction during the procedure. The nurse must ensure appropriate precautions or alternative imaging are considered. Choices B, C, and D are not directly contraindicated for a CT scan with contrast. Smoking history, metformin use, and controlled hypertension do not typically impact the safety or feasibility of the procedure.

Correct Answer: D

Rationale: The correct next step for the nurse is to measure the area of crepitus. Crepitus indicates subcutaneous emphysema, which is a serious condition requiring monitoring. Applying a pressure dressing (Choice A) could worsen the condition by trapping air under the skin. Administering an oral antihistamine (Choice B) is not indicated for crepitus. Assessing for allergies to cleaning agents (Choice C) is not the priority when dealing with crepitus and subcutaneous emphysema.

Correct Answer: B

Rationale: Verifying the correct placement of a nasogastric tube before each feeding is essential to prevent aspiration and ensure that the tube is properly positioned in the stomach or intestine. This action is a priority to maintain client safety. Flushing the tube with water every 4 hours is important for tube patency but is not the priority over verifying placement. Securing the tube with tape and keeping the head of the bed elevated are crucial but are considered secondary measures compared to confirming the correct tube placement.

Correct Answer: B

Rationale: The correct answer is B. Using nitroglycerin as needed, every 5 minutes, up to 3 doses, is the appropriate management for angina at rest. This helps dilate blood vessels, improving blood flow to the heart. Choice A is incorrect because chest pain that persists at rest should be addressed immediately, not waiting for 30 minutes. Choice C is incorrect as avoiding physical activity is not a recommended approach during an angina episode. Choice D is incorrect because nitroglycerin should be used during chest pain episodes, not as a preventive measure before physical activity.

Correct Answer: C

Rationale: The correct answer is C: 'Check for bowel movement and changes in stool.' Intussusception can cause obstruction in the bowel, leading to symptoms like abdominal pain, vomiting, and 'currant jelly' stools. Monitoring for changes in bowel movement, especially the passage of 'currant jelly' stools, is crucial for early detection of worsening conditions. Choices A, B, and D are important assessments in pediatric care but are not as specific or crucial as checking for changes in bowel movement in a child diagnosed with intussusception.