A 6-week-old infant with poor weight gain is scheduled for a pyloromyotomy. Which pre-operative nursing action has the highest priority?

Choice A: Increasing oral fluids may help with hydration, but it will not reduce skin flushing caused by lisinopril. Lisinopril is an angiotensin-converting enzyme (ACE. inhibitor that dilates blood vessels and lowers blood pressure. Flushing occurs due to increased blood flow to the skin.

Choice B: Nitroglycerin is a vasodilator that relaxes smooth muscle in blood vessels and reduces chest pain caused by angina. It is not indicated for skin flushing caused by lisinopril. Moreover, nitroglycerin can lower blood pressure further and cause hypotension, headache, dizziness, and fainting.

Choice C: Going to an emergency department is not necessary for skin flushing caused by lisinopril. Flushing is not a sign of an allergic reaction or anaphylaxis, which would require immediate medical attention. Flushing is also not a symptom of a heart attack or stroke, which would present with other signs such as chest pain, shortness of breath, arm numbness, or slurred speech.

Choice D: Reassuring the client that facial flushing is a common side effect of lisinopril is the best action for the nurse to take. Flushing is not harmful or dangerous, and it usually subsides within a few hours. The nurse should explain the mechanism of action of lisinopril and its benefits for lowering blood pressure and preventing angina. The nurse should also advise the client to monitor his blood pressure regularly and report any signs of hypotension, such as dizziness, lightheadedness, or fainting.

Choice A reason: Marking an outline of the "olive-shaped" mass in the right epigastric area is not a priority nursing action. The mass is caused by hypertrophy of the pyloric sphincter, which obstructs gastric emptying and causes projectile vomiting. The mass may not be palpable in all cases.

Choice B reason: Instructing parents regarding care of the incisional area is a post-operative nursing action, not a pre-operative one. The parents will need to learn how to keep the incision clean and dry, monitor for signs of infection, and administer pain medication as prescribed.

Choice C reason: Monitoring amount of intake and infant's response to feedings is important, but not the highest priority. The infant may have difficulty feeding due to nausea, vomiting, and abdominal pain.