The perinatal nurse explains to the student nurse that in the fetal circulation

The perinatal nurse explains to the student nurse

This preview shows page 6 - 9 out of 32 pages.

The perinatal nurse explains to the student nurse that in the fetal circulation, the lowest level of oxygen concentration is found in the umbilical arteries = after delivery it constricts in response to ^ blood oxygen levels and . Embryo and Fetal Development : first 8 wks= Organogenesis Ectoderm Mesoderm Endoderm After 9th wk = Fetus Fetus Circulation : ^ levels of oxygenated blood enter the fetal circulatory system from the Placenta -> Umbilical Vein Ductus Venosus connects Umbilical Vein to Inferior Vena Cava Foramen Ovale (opening between L & R atrium) after delivery shunt closes within 3 months from blood returning to the L atrium Ductus Arteriosus (connects Pulm Artery to Descending Aorta)
Image of page 6
Ductus Venosus connects Umbilical Vein to Inferior Vena Cava Foramen Ovale (opening between L & R atrium) after delivery shunt closes within 3 months from blood returning to the L atrium Ductus Arteriosus (connects Pulm Artery to Descending Aorta) after delivery it constricts in response to ^ blood oxygen levels and prostaglandins Placenta Development: formed from both fetal and mother tissue Chorionic Membrane (trophoblast & chorionic villi) Form fetal blood vessels of the placenta Endometrium (decidua) = 3 layers Decidua Basalis : forms maternal side of the placenta > Placenta is divided into lobes “cotyledons” > Placental membrane separates maternal/fetal blood from mixing but allows for exchange of nutrients, gases and electrolytes through diffusion and active transport Major Hormones of the Placenta Progesterone : < in uterine contractility & facilitates implantation Estrogen : “enlargement” breasts and uterus hCG : + preg test, ^ in 1st trimester as it stimulates corpus luteum to keep secreting estrogen and progesterone until placenta is able to secrete it (6-7wks) hPL : promotes fetal growth by regulating glucose and stimulates breasts to lactate Umbilical Cord = 1 vein (oxygenated blood) and 2 arteries (deoxygenated blood) A . V . A
Image of page 7
-
Image of page 8
Image of page 9

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture