What are the maternal adaptation in pregnancy?
expanded intravascular volume
increased min ventilation
increased progesterone activated hepatic metabolism
increased renal blood flow and GFR
increased thinning of fetomaternal barrier w/ advanced gestation
increased body fat
increased cardiac output
decreased peripheral vascular resistance for plasma volume expansion
decreased GI motility
decreased albumin
What haps when intravascular volume is expanded?
body gets diluted –> higher dose MAY be needed to BUT there is less protein binding –> more drug in free space –> balances out
Why do women get morning N&V?
the increase in progesterone
Which maternal adaptation has the most impact on the body?
increase in renal blood flow and GFR
Why do pregnant women get constipation?
decreased GI motility
What haps when there is thinning of fetomaternal barrier w/ advanced gestation?
when mom is infxn’d the baby is at very high risk for same infxn
What is the purpose of the placenta?
prevents the mixing of the blood between mom and baby
can also be used to check the gender of the baby and genetic abnormality
What type of diffusion haps in the placenta?
passive diffusion
Why is passive diffusion imp re: the placenta?
small, lipophilic, and low protein bound rugs can pass through the placenta
When is the placenta the most permeable?
early and late
middle pregnancy is LEAST permeable
What haps to the drug in the fetus?
some go into the heart, some go right into the bloodstream - drug is ACTIVE and does NOT go through metabolism
Fetus brain to be aware?
FIRST to develop
NO BBB –> highly vulnerable to drugs
When is the fetus most vulnerable to physical defect/malformation?
early: 3-9wks
What types of abnormalities can occur - early stages?
neural tube cardiac extremities cleft lip ears
When is the fetus most vulnerable to CNS defects?
later: 9-38wks
What drugs should be used in pregnant moms?
low lipid solubility* high protein binding* high molecular wt* *think about the placenta and what can and can't cross lowest dose possible short half life
What are the drugs called that can cause severe/fatal defects?
teratogenic drugs
What are Category X drugs?
Isotretionin
methotrexate
warfarin - use heprin!
What are Category D drugs?
Anticonvulsants
Antithyroid
Why are anticonvulsants used? Are they useful to the baby?
some docs think anticonvulsants are outweigh the benefit vs harm
causes the baby to be at higher risk for epilepsy when used
Baby has scalp defect and goiter - cx of drug? What should be advised for the mom?
antithyroid
tx the thyroid prob before getting pregnant
Mom has aches and pains - drug?
aceteminophen
Mom has constipation and N/V?
diet - no drugs
Mom has GERD? What to avoid?
smaller meals upright after eating first line - tums second line - zantac/pepcid/reglan last resort - PPI and H2 blockers avoid - cimetidine
Mom has infxn - what to AVOID?
nitrofuratonin - NOT in 3rd trimester
Sulfa - BEFORE 3rd trimester
Mom has HTN - what to AVOID?
thiazide and ACE - I
Mom has depression?
may discontinue if BOTH mom and provider is OK
SSRI and TCA
Mom has DM II?
Insulin
Mom has allergic rhinitis - what to AVOID?
pesudoephderine
cetrizine
loratidine - ESP during 1st trimester
What drugs to avoid in moms?
tetracylcine
antifungal therapy unless topical
erythromycin
streptomycin
What vaccines to avoid in pregnant moms?
MMR
smallpos
varicella
Pregnant mom’s drugs are safe in breast feeding moms - Y/N? Then who?
NO
if safe for BABY then OK for breast feeding
What factors to consider when breast feeding?
volume of distribution
high % of maternal protein binding - decrease exposure
large molecular wt - decrease exposure
hydrophilic - b/c milk is fat
What to avoid in breast feeding moms?
ergotamine HD narcotics aminoglycosides sulfonamides OCP benzodiazapine beta blockers
What renal infxn risk increases in pregnancy?
ASU
UTI
pyelonpehritis