Transition from placental to pulmonary respiration
Respiration:
Delivery of oxygen in exchange for the metabolic end-product carbon
dioxide.
Placenta or lungs:
Carbon dioxide is released in exchange for oxygen.
Hemoglobin:
Molecular basis of gas exchange.
Sufficient blood volume is needed for hemoglobin to reach all organs.
Transition at birth:
Blood circulating to the placenta needs to be redirected to the infant's
lungs.
Capillaries surrounding the alveoli must be filled with blood before
the first breath.
Carbon dioxide is released into the alveoli, exhaled, and the first
inspiration follows.
Mercer JS, Skovgaard RL. Neonatal transitional physiology: a new paradigm.
J Perinat Neonatal Nurs. 2002 Mar;15(4):56-75.