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Conrad Simon (1963-1995)
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Eileen Nicole Simon
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    Exhalation before the first breath?

    Prevailing opinion holds that opening of the alveoli is a passive response to
    movements of the diaphragm in the newborn infant – an initial respiratory
    effort made immediately following birth in the healthy child.  Jäykkä's
    experiments included simulation of diaphragm movement, along with
    ventilation of one lung and ventilation plus fluid filling of the capillary bed of
    the other.

    Jäykkä used the un-inflated (atelectatic) lungs of fetuses that had died before
    birth.  Injection of fluid (macrodex solution) into the pulmonary artery of one
    lung resulted in expansion of the alveoli of that lung.  Expansion occurred first
    in the most distal alveoli, with expansion in three stages of the more proximal
    alveoli toward the center of the lung – before initial function of the bronchial
    airway the alveoli deepest in the lungs were first to inflate!  Consider the
    added effect of carbon dioxide released by hemoglobin to be exhaled from
    these newly opened alveoli.

    An initial exhalation may precede the first breath.

    Carbon dioxide from the circulation may perhaps initiate inflation of the
    alveoli.  If circulation to and from the placenta is abruptly clamped off, where
    will the blood needed for the lungs come from?  The lungs take priority at
    birth.  If the blood needed is drained from the brain, the result may be the
    kind of ischemic damage found in monkeys subjected to asphyixa at birth --
    and with an Apgar score of 10.

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