Postnatal Kardiyovasküler Adaptasyon

Fetal dola?ım plasenta yoluyla fetuse gelen maternal kan ile sağlanır. Umbilikal ven aracılığıyla bebeğe geçen yüksek oksijen ta?ıyan kan karaciğeri duktus venozus yoluyla bypass ederek inferior vena kava aracılığıyla sağ atriyuma ta?ınır. Umbilikal venle gelen kanın çok az bir miktarı karaciğeri sular. İnferior vena kava ile sağ atriyuma gelen oksijenli kanın, buradaki kapakçıklar sayesinde süperior vena kavadan gelen dü?ük oksijenli kan ile karı?madan, doğrudan foramen ovaleye doğru yönlendirilerek sol atriyuma geçmesi sağlanır. Böylelikle oksijenin beyin, koroner damarlar gibi vital organlara akı?ı sağlanmı? olur. Sol atriyum aracılığıyla sol ventriküle gelen kan aorta kanalıyla santral sisteme ve üst ekstremitelere doğru akar. Dü?ük oksijen içeren superior vena kava aracılığı ile sağ atriyuma gelen kan ise sağ ventriküle ve pulmoner artere doğru yönelir. Yüksek pulmoner basınç nedeniyle pulmoner arterdeki kanın çoğu duktus arteriozus aracılığıyla karotid ve koroner arterlerin orijininden sonra aortadaki kan ile karı?arak alt ekstremiteye doğru yol alır. Alt ekstremite ve aortadan gelen kan umbilikal arterler içinde plasentaya doğru akar ve maternal dola?ıma geçer. Fetal dola?ımdaki 3 köprü önemlidir:

Postnatal Cardiovascular Adaptation

Fetus depends on placental circulation in utero. A successful transition from intrauterin to extrauterine life depends on succesful physiological changes during labor. During delivery, fetus transfers from a liquid environment where oxygen comes via umbilical vein to air environement where oxygenation is supported via air breathing. Endocrinological changes are important for fetus to adapt to extrauterine life. In addition to these, cord clemping plays a crucial role in postnatal adaptation. Establishment of neonatal postnatal life and succesful overcome, the fetal cardiovascular transition period are important to stay on. Key words: Fetus, transition period, postnatal adaptation.

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