Chapter 29 - Adjustments of Infants at birth, lacation Flashcards
What can happen to the baby when it is being squished in the birth canal during delivery?
Maybe it would explain Erich since he sat in there for 4 friggin hours!
Hypoxia because umbicial cord is compressed.
During birth the fetus releases Epinephrine and norepinerphrine (fight or flight chems). WHy?
These clear the lungs and alters the phusiology of the lungs to prepare them to breathe in air.
- mobilize readily usable nutrients for cellular metabolism and promote an increased flow of blood to brain and heart!
What is in the lungs that must be absorbed at birth?
Amniotic fluid
Describe the process where the baby goes from getting O2 from mom in blood to getting O2 from air and it’s own lungs
– in tuterus baby’s lungs are collapsed have some amniotic fluid.
non-functioning
surfactant production begins at the end of 6th month
-at delivery :
*O2 from mom stops, *amniotic fluid in lungs is absorbed,
*CO2 isn’t being removed (umbilical cord is cut) so it builds up in blood
*rising CO2 stimulates medulla oblongata, respiratory muscles contract and baby pulls in first breath (will be very large inhale to fill collapsed lungs)
in first 2 weeks of life baby can have a respiration rate of 45 decreasing to the normal level of 12
There are many adjustments a new baby makes as soon as she is born. Cardio vascular ones are large because the baby’s heart now has to connect to the newly function lungs to spread O2 about. How does this happen?
No questions in any quiz touched on any of this topic.
,cardiovascular system changes:
• the closing of the foramen ovale between the atria of the heart occurs at the moment of birth, closed by 2 flaps of septal heart tissue that fold together and permanently fuse
• closing of the foramen ovale diverts deoxygenated blood to the lungs for the first time.
Once lungs are working
• Ductus arteriosus shuts off because of contractions of smooth muscle in its wall (can take up to 3 months to close completely
Cardio vascular changes also happen in veins and arteries as newly oxygenated blood begins to circulate.Describe the major changes.
Again no questions ever asked on this topic.
Once umbilical cord cut there is no blood flow into
• umbilical arteries, they fill with connective tissue and distal portions become medial umbilical ligaments
• Umbilical vein becomes ligamentum teres (round ligament) of the liver
• The ductus venosus (which connected umbilical vein to inferior vena cava in baby and bypassed the liver) collapses and the venous blood from the viscera of the baby flows into the hepatic port to liver to hepatic vein to inferior vena cava (engaging the liver)
• Pulse may range from 120-160 bpm
• After birth increased access to oxygen stimulates an increase in red blood cell and hemoglobin production.
• White blood cell count at birth is very high (as high as 45,000 cells per microliter) decreases rapidly to normal levels by the 7th day.
What is lacation?
- is the production and ejection of milk from the mammary gland
What is the principal hormone in milk production?
Why is milk not produced during pregnancy?
Prolaction (PRL)
it increases during pregnancy but progesterone (produced to keep cervix tight) inhibits milk production
– this hormone stimulated by baby suckling
Explain the steps in Milk Ejection Reflex.
Is this a positive or negative feedback loop?
Positive feedback loop. More suckling produced more milk and the more milk makes baby drink more and then he suckles more!
STEPS
milk ejection reflex -
baby sucks nipples
increases touch sensitive sensory neurons in nipples
which send signals to hypothalamus and posterior pituitary
which increases oxytocin in blood
which causes contraction of myoepithelial cells in mammary glands which results in milk ejection
good diagram in book for visual
What hormone causes milk to be ejected or “let down”?
Our friend OXYTOCIN! also makes uterus contract so helps uterus return to smaller size right after birth
How does the milk get from the milk ducts to the baby?
oxytocin stimulates contraction of the myoepithelial (smooth muscle-like cells) that are around the glandular cells and milk ducts.
This compression moves the milk from the alveoli of the glands into the ducts where it can be suckled
For up to 4 days, the mom actually doesn’t produce milk for the baby. What in the world are the little guys drinking for the first couple of days?
Colostrum
it is a cloudy fluid that contains less lactose and almost no fat. It does have important antibodies in it.
it is less nutritious than milk
Why are people so crazy for breast feeding?
I mean when the baby gets teeth, it can be painful. Not to mention cracked nipplies, sore nipples and feeling like a milk factory!
mostly nutritional benefits for baby
Beneficial cells in breast milk –
• white blood cells (neutrophils & macrophages) ingest microbes in baby’s GI tract
• macrophanges produce lysozyme and other immune system components as well as GI duties
• antibodies from mom to fight disease causing microbes
• two milk proteins bind to nutrients that many bacteria need to grow and survive (B12 binding protein ties up vitamin B12, lactoferrin ties up iron)
• fatty acids can kill viruses by disrupting their membranes
• lysozyme kills bacteria by disrupting cell membranes
• interferons enhance the antimicrobial activity of immune cells
People claim that feeding a baby breast milk can provides slight reduction in risk of lymphoma, heart disease, allergies, respirator and GI infections, ear infections, diarrhea, diabetes and meningitis. Seems like a lot, is this T or F?
True
What is the cause of Down Syndrome?
3 rather than 2 copies of at least part of chromosome 21
