A nurse is assessing an infant and suspects coarctation of the aorta based on which assessment finding.

Choice A rationale Excessive crying in an infant is a non-specific sign and may indicate general distress, hunger, pain, or discomfort, but it is not a characteristic or definitive sign of coarctation of the aorta. This congenital heart defect involves a narrowing of the aorta, leading to specific hemodynamic changes like blood pressure differences. Non-specific symptoms should prompt a wider assessment, but they do not confirm this diagnosis. Choice B rationale Hypotension, or abnormally low blood pressure, is usually not a primary finding in the proximal arteries (upper extremities) in coarctation of the aorta. Due to the aortic narrowing, blood pressure is typically elevated in the arms and head, while it is low or absent in the lower extremities, reflecting the obstruction distal to the great vessels. The normal systolic blood pressure for a term neonate is 65 to 90 mmHg. Choice C rationale Increasing inspiratory stridor, a high-pitched, harsh sound, indicates upper airway obstruction, typically from conditions like croup, epiglottitis, or foreign body aspiration. It is a respiratory finding and is not a direct consequence or associated symptom of coarctation of the aorta, which is a cardiovascular defect affecting systemic blood flow dynamics. Choice D rationale Coarctation of the aorta is a localized narrowing, usually distal to the origin of the subclavian artery. This narrowing causes increased resistance to flow to the lower body. As a result, blood pressure is higher in the upper extremities and head, leading to bounding radial and brachial pulses, while the pulses in the femoral and pedal arteries of the lower extremities are often weak, delayed, or absent, confirming the obstruction.