fetal/Neonate/peds assessment Flashcards
Fetal circulation is characterized by
- High PVR
- low SVR
in fetus, oxygenated blood bypasses lungs via:
- Ductus arteriosus
- ductus venous
- Foraman ovale
Ductus arteriosus
blood from RV bypasses lungs and routes to aorta
pulmonary artery–>aorta
Ductus venosus
routes oxygenated blood away from sinusoids of the liver
Foramen ovale
intracardiac
oxygenated blood in IVC is directed toward atrial septum and passed through foramen ovale, entering L side of circulation
connects R and L atria
How does foramen ovale close
changes in lung pressure/expansion–>changes in cardiac pressure–>changes direction of blood flow–>hole eventually closes
permanently closed by 2-3 months
In the neonate, cardiac ouput is solely dependent on
heart rate, because of the limitation of contractility
What system is dominant in infant
PNS dominance, sympathetic is immature
Fetal hemoglobin has _____ affinity for O2 compared to adult hemoglobin
higher affinity = left shift
facilitates oxygen uptake as fetal blood circulates through placenta
increases binding of oxygen to fetal hgb
allows fetus to exist in relatively low PaO2 environment
Infant blood oxygemoglobin curve
shift right (release)
infant blood volume compared to adult
infant blood volume higher in mL/Kg than adult
up to age 3
Surfactant____ surface tension
Decreases surface tension in alveoli
decreases alveolar collapse
surfaction production begins at
22-26 weeks
treatment ARDS infant
synthetic surfactant
PPV/CPAP
mechanical ventilation
Neonate: chest wall movement during inspiration
chest wall collapses inward (paradoxical breathing)
