In a neonate with a hemodynamically significant patent ductus arteriosus and ductal steal physiology, which clinical finding best reflects this phenomenon?

• A. Decreased pulse pressure
• B. Bounding peripheral pulses
• C. Systemic hypertension
• D. Narrowed pulse pressure

Answer: (B)

In a neonate with a hemodynamically significant patent ductus arteriosus, blood flows from the aorta into the pulmonary artery through the PDA. This diastolic runoff lowers the aortic diastolic pressure while systolic pressure remains relatively high due to increased stroke volume, creating a widened pulse pressure. That widened pulse pressure is felt as bounding peripheral pulses—the hallmark sign of ductal steal in this setting. So the best clinical reflection of this phenomenon is the presence of bounding pulses.

Other patterns, like decreased or narrowed pulse pressure, don’t fit the ductal steal physiology, and systemic hypertension isn’t typical in this scenario.