Blood from this vessel streams preferentially through the foramen ovale, resulting in a fetal preductal sat of ~65%, a few points higher than the sat in the descending aorta (60%)
What is the ductus venosus?
The lung volume that increases once ventilation with a positive ratio of inspiration to expiration is established
What is Functional Residual Capacity?
The normal direction of the fetal ductus arteriosus shunt
What is right to left?
Failure of the aorticopulmonary septum to follow a spiral course
What is TGA?
This is responsible for the marked increase in SVR when the umbilical cord is clamped
What is separation from the low-resistance placenta?
The structure that provides initial gas exchange for the fetus, prior to placental dominance at 10 weeks gestation.
What is the yolk sac?
The fetal lungs are hyperexpanded compared to postnatal lungs due to accumulation of fluid related to secretion of this electrolyte by the distal pulmonary epithelium
What is chloride?
The principal modulator of fetal cardiac output
What is heart rate?
Failed formation of the endocardial cushion
What is AV canal?
The condition required for closure of the foramen ovale
What is left atrial pressure greater than right atrial pressure?
The approximate oxygen saturation in the fetal umbilical vein
What is 70 to 80% ?
The amount of time during a normal transition that a pre/post ductal saturation gradient is observed
What is approximately 15 minutes?
Before the bone marrow takes over around 6 months of gestation, this organ is primarily responsible for fetal erythropoesis
What is the liver?
Downward displacement of the septal and posterior leaflets of the tricuspid valve
What is Ebstein anomaly?
Neonatal cardiac output is reduced if the cord is clamped prior to the onset of ventilation as a result of this.
What is decreased LV preload?
The blood vessel in the fetus with the lowest oxygen saturation, about 40%
What is the IVC?
The two hormones that promote clearance of airway fluid in the newborn by stimulating active Na absorption
What are cortisol and thyroid hormone?
Because fetal hemoglobin has increased affinity for oxygen, the oxyhemoglobin curve is shifted in this direction
What is to the left?
Failure of the connection of the 4th and 6th branchial arches
What is coarctation of the aorta?
The substance produced due to sheer stress from increased pulmonary blood flow--which further decreases PVR
What is nitric oxide?
The organ perfused with the most highly saturated blood in the fetal circulation
What is the liver?
In addition to suppressing the production of NO and PGI2, fetal hypoxemia increases PVR and triggers vascular remodeling through activation of this substance
What is Hypoxia Inducible Factor 1?
The point in gestation when fetal cortisol levels begin to increase
What is 30 weeks?
Unequal division of the conotruncus
What is tetralogy of Fallot?
This mediates relaxation of pulmonary vascular smooth muscle in response to oxygenation
What is cGMP-dependent protein kinase?