Fetal Resuscitation Flashcards
Neurologic injury in the fetus depends on?
Duration of hypoxia from disruption of placental flow of oxygen and nutrients
Maternal infection and inflammation can cause what?
Neuro developmental abnormalities
- schizophrenia
- autism
What is complete asphyxia?
Total placental abruption
Umbilical cord occlusion
What is incomplete asphyxia?
Anytime oxygen delivery is inadequate to meet needs
Causes of incomplete asphyxia
Aortocaval compression
HTN
Hypotension…
Fetal assessment: neurobehavioral scale
HR
Motor activity
Existing behavioral state
Responsiveness to external stimuli
Anesthesia and fetal brain injury
All needs more studies
- labor anesthesia
- parenteral opioids
- neuraxial
- inhalation agent
What drug is thought is help with neuroprotection?
Magnesium
What may improve outcomes in neonates at risk for hypoxic ischemic encephalopathy?
Hypothermia
Fetal circulation
Placenta Umbilical vein and ductus venosus To inferior vena cava Right heart Foremen ovale to Left heart Ascending aorta Patent ductus arteriosis Descending aorta Blood returns to placenta via umbilical arteries
What affect does clamping the umbilical cord have?
Increase SVR
Why does lower oxygenated blood supply the lower body while the more oxygenated blood supplies the upper?
PVR is higher than SVR so most of the blood from the RV is pushed through ductus arteriosis into lower body circulation
-lower body also requires less O2 than brain and heart
Decreased PVR occurs from what? Leading to what?
Expansion of the lungs and increased alveolar oxygen tension and pH
Greater pulmonary artery blood flow
What does increased pulmonary artery blood flow cause?
Improved oxygenation and higher LA pressure > diminishes shunting across foramen ovale
What causes constriction of the ductus arteriosis and closure of the foramen ovale?
Increased PO2 and SVR
Decreased PVR
Fetal breathing movements are seen when? How do they change?
11 weeks gestation
Increase with gestational age
Decrease days before onset of labor
What is contained in the fetal lungs?
Ultra-filtrate of plasma (fluid)
- partial reabsorption
- 2/3 expelled
What increases residual fluid in fetal lungs?
Preterm
C-section
-vaginal delivery helps push out some fluid
First breath occurs when? Establishes what?
~ 9 seconds after delivery
FRC
When is surfactant present in the alveoli?
By 20 weeks gestation
When is surfactant present within the lumen of the airways?
28-32 weeks gestation