Key Concepts
Overview
Fetal circulation differs dramatically from neonatal circulation because: (1) the lungs are non-functional as gas exchangers (placenta performs this role), (2) the liver receives partly oxygenated blood from the placenta, and (3) three unique shunts divert blood away from the lungs and liver. At birth, these shunts close as the lungs expand and vascular resistances shift. On the exam, writers often pair stable-sounding options with unstable data—notice the mismatch before you commit. If the stem names a license or role, reread that line; scope errors are classic trap answers even when the clinical topic is familiar. Run a 60-second scan: breathing work and oxygenation, perfusion and end organs, neuro baseline, likely infection sources, and devices that can fail quietly. When two answers feel partly right, pick the one that reduces imminent harm and matches orders for the role you were given. Train yourself to state the primary risk in one short phrase before you read the options so distractors do not rewrite your priority list. On the exam, writers often pair stable-sounding options with unstable data—notice the mismatch before you...