Peds Test 3 Flashcards
Vasculogenesis vs Angiogenesis
V= making new blood vessels form angioblasts/blood islands= major vessels A= vessels sprout from existing blood vessels= remainder of vascular system
Blood Cells Come from
hematopoietic stem cells which come from mesoderm surrounding aorta near kidney
-colonize in liver (source of first BC)
-liver colonizes bone marrow and liver loses RBC making
2-7 months= liver is hematopoietic organ
after 7 months= bone marrow
Aortic Arch System
from vascular endothelial growth factor (VEGF)
6 Pairs of Aortic Arches
all come from aortic sac region (number 5 goes away)
1) dorsal aortas= maxillary artery
2) stapedial artery (ear)
3) common carotid
4) L= aortic arch (b/w L common carotid and L. subclavian)
R= proximal R. subclavian
6) L proximal= L pulm artery
L distal= ductus arteriosis= ligamentum arteriosum
R proximal= R pulm artery
Aortic Sac Becomes.. Right Dorsal Aorta Left Dorsal Aorta Right Intersegmental artery Left Intersegmental artery
1) asc aorta, aortic arch, brachiocephalic artery 2 R. subclavian 3) distal aortic arch, desc aorta 4) R. subclavian 5) L subclavian
Sinus Venosus
major entry point into common atrium
- central, transverse, horns (comprised of vitelline (from yolk= becomes hepatic vein), umbilical (from placenta= Right becomes subclardionhepatic anastomosis), common cardinal veins(drain fetus body)
- –R UV goes away, L VV, L CCV
- L sinus horn= oblique vein of left atrium and coronary sinus
- R sinus horn= grows and forms smooth wall of right atrium= sinuatrial orifice (which have valves)
- Left venous valve= fuses with atrial septum
- Superior R valve= disappears
- Inferior R valve= valve of inferior vena cava and valve of coronary sinus —valves are remnants of L horn
Definitions: Placenta, Umbilical Artery/Vein, Fetal Capillaries, Intervillous Space
- site of exchange with mother
- artery- carries deoxy blood away from fetus to placenta
- vein- carries oxygenated blood to fetus
- (branched from umbilical) into intervillous spaces in placenta
- spaces filled with maternal blood from uterine arterioles (drained by uterine veins)
Placenta
very low resistance= more gas exchange/flow
- uses mother’s uterine blood vessels
- no direct contact with fetus blood- just exchanges gas, by diffusion and nutrients/electrolytes
- fetus Hgb has 50% more and carries 35% more oxygen (higher affinity)
- O2 extracted = 20-30 mL O2/min == depends on delivery NOT rate of diffusion
- Late first trimester fetus makes complement
- –gets IgG from mom! = provides passive immunity
- Hormones= placent produces progesterone and exterior
Umbilical Blood Vessels
2 arteries, 1 vein
80% sat from umbilical vein- 1/3 to liver, 2/3 ductus venous IVC
67% once in IVC (cuz mixes with deoxy blood)
58% returning in umbilical artery
Fetal Lungs
filled with fluid= SUPER high resistant
Fetal Circulation
blood from IVC= skips RV and goes thru foramen ovale= perfuses brain and myocardium
blood from SVC= goes to RV, pumped to PA
95% bypasses lungs goes through ductus arterioles to descending aorta= perfuses fetal tissue
Blood leaving fetus
goes thru common iliac to internal iliac= umbilical artery= placenta
Ductus Arteriosus
Ductus Venosus
A= from PA to aorta V= from umbilical vein to IVC (passing the liver)
At birth 3 shunts close
ductus arteriosus, venosus, foramen ovale
Umbilical Vein becomes
closes after umbilical artery and remains attached to the liver as ligament teres hepatis
