Week 3- Fetal-Neonatal Transition Flashcards
Common drugs with teratogenic effects
Warfarin
Thalidomide
Epilepsy
Retinoids (e.g. Isotretoin)
Acei, Alcohol, Antineoplastics
Third element (Li), tetracylclines
Oestrogens and other hormones
What kinds of drugs get stuck in breastmilk? What kinds of drugs get stuck in the stomach
Weak bases because milk is more acidic than plasma
B+ H+ –> BH+
Weak bases get stuck in the stomach because it is less acidic than adults, which means that weak acids are better absorbed (e.g. penicillin)
How does neonatal physiology affect the dosing/absorption/elimination of aminoglycosides, morphine, penicillin, ampicillin + gentamycin
Penicillins are acid-labile and are more bioavailable in babies
Aminoglycosides: water soluble, babies have higher TBW
Morphine is lipid soluble and babies have immature BBB
Ampicillin + gentamycin: decreased GFR, so you need longer dosing intervals to prevent accumulation
Which antibody can be transferred across the placenta?
IgG
Why are neonates with prolonged rupture of membrane more likely to get GBS?
- no anti-polysaccharide Abs means more susceptible
Why are neonates at a higher risk of rapidly spreading intracellular infxn? Why are neonates at risk of intracellular infxn in utero (vs. extracellular)?
Naive T-cells
Placenta filters extracellulalr bigs, but some intracellular things get by (HSV, CMV, TB, VZV, EV, Lyme, toxoplasmosis, rubella)
An early post-natal sepsis is more likely to be….a late (>5 days) postnatal sepsis is more likely to be….
early: GBS, E. coli, listeria, enterovirus
late: pseudomonas, S. aureus, CNS, anaerobes
What phase of development should fetal lungs be in to be born?
At least saccular (~24 wks)- this when type II cells appear
When should a neonate have reached it’s FRC after birth? When should the ductus arteriorus have closed after birth?
In an hour. 2/3 fluid cleared by capillaries and lymphatics
1/3 cleared by vaginal squeeze
DA closure by 24 hrs…give prostaglandins to keep open and NSAIDs to close
Composition of surfactant: 80% phospholipids, 10% protein, 10% neutral lipid
What are the benefits of delaying cord clamping?
Increase baby’s iron stores, Hb
In pre-term, reduces the risk of intraventricular hemorrhage
APGARS scoring
Appearance:
- blue =0
- acrocyanosis=1
- pink all over=2
Pulse
- absent= 0
- <100 = 1
- >100= 2
Grimace
- no response to pain=0
- grimace to pain =1
- cough/cry/sneeze to pain=2
Activity
- flaccid= 0
- some flexion =1
- active motion =2
Respiration
- none= 0
- slow and irregular= 1
- crying =2
APGARs at 1 and 5 and then every 5 minutes until they have a score above seven.
What parameters does the ACoRN score include?
RR
O2 requirement
retractions
grunting
breath sounds on auscultation
prematurity
Transient tachypnea of the newborn vs. respiratory distress syndrome vs. meconium aspiration
TTN: inadequate clearance of pulmonary fluid (should be only 24-48 hrs), would see interstitial markings and pulmonary edema on xray
RDS (aka hyaline membrane dz): inadequate surfactant –> progressive collapse of alveoli/terminal bronchioles. would see air bronchograms on xray and ground glass
MAS: patchy atelectasis +/- consolidation, hyperinflation, leads to chemical pneumonitis. 10-15% of all births have MSAF, of this 5% get MAS and of these 5% of these die
How much fetal lung fluid is produced per day in the term infant?
250-300 mL of fetal lung fluid/day
