Pharm Antenatal and Perinatal - Wolff

Question 1

• misoprostol
• dinoprostone
• carboprost
• oxytocin
• ergot alkaloids

Answer 1

labor induction/control post-partum hemorrhage

Question 2

• cortisol
• betamethasone
• dexamethasone

Answer 2

corticosteroids

Question 3

• terbutaline
• indomethacin
• nifedipine
• MgSO4
• atosiban

Answer 3

tocolytics (delay labor)

Question 4

what drugs are used to keep the ductus arteriosus open?

Answer 4

alprostadil, misoprostol

Question 5

what drugs are used to close a PDA?

Answer 5

indomethacin, ibuprofen

Question 6

• a-methyldopa
• labetalol
• hydralazine
• Na-nitroprusside

Answer 6

anti-hypertensives in pregnancy

Question 7

what are the key factors thought to regulate phase 1 of parturition (labor)?

Answer 7

nitric oxide, hCG, progesterone

Question 8

what are the key factors thought to regulate phase 2 of labor?

Answer 8

gap junction receptors, prostaglandins, hyaluronan

Question 9

what are the key factors thought to regulate phase 3 of labor?

Answer 9

oxytocin, estrogen

Question 10

what are the key factors thought to regulate phase 4 of labor?

Answer 10

inflammatory cell activation

Question 11

process in which collagen and glycosaminoglycans are broken down in the cervix by matrix metallo-proteinases
- cervix becomes thin (effacement) and dilates

Answer 11

cervical ripening

Question 12

synthetic prostaglandin E1 analog

• induces uterine contractions
• used to terminate intrauterine pregnancy if <70 days (in combination with mifepristone)
• off-label cervical ripening
• stable at room temp, cheap!

Answer 12

misoprostol

- causes NVD, can cause hypoxia in fetus

Question 13

what are the contraindications of misoprostol?

Answer 13

pregnancy (unless aborting)

previous c-section (disrupts uterine scar -> rupture!)

Question 14

synthetic prostaglandin E2 analog

• induces uterine contractions AND promotes cervical ripening
• available as gel, vaginal insert, or suppositories
• much more expensive than miso, needs to be refrigerated

Answer 14

dinoprostone

• causes NVD, fever (not responsive to NSAIDs)
• can cause hypoxia in fetus d/t tachysystole

Question 15

synthetic prostaglandin F2a analog

• induces uterine contractions
• used to induce abortion b/w 13-20wks (if other methods don’t work)
• also used for post-partum hemostasis for refractory bleeding
• given IV, is expensive

Answer 15

carboprost

• causes HTN and pulmonary edema, is a potent vasoconstrictor (unlike PGE2)
• tends to reduce body temp (unlike PGE2)
• dizziness, gagging, heartburn, cough… lots of other side effects

Question 16

posterior pituitary hormone

• increases force, frequency, and duration of uterine contractions (both induction and augmentation, but should be used with caution)
• administered IV, is cheap

Answer 16

oxytocin
- can cause water intoxication (rare) because structure is similar to ADH
NOTE: only works in uterus AT TERM (cervix needs to be ripe before uterus contract, otherwise it can rupture)

Question 17

stimulates adrenergic, dopaminergic and serotogenic receptors

• causes prolonged tonic uterine contractions (not good for fetus)
• constricts arterioles and veins
• used POST-PARTUM to increase uterine tone and stop bleeding
• oral, IV or IM admin

Answer 17

ergot alkaloids (constrictor from rye fungus)

Question 18

what are the contrindications of ergot alkaloids?

Answer 18

HTN, hypersensitivity

- very rarely can cause psychosis or convulsions (the whole witchcraft thing)

Question 19

what drug class works well for cervical ripening, and can cause uterine contractions at any time during pregnancy (used for abortions)?

Answer 19

PGE analogs (prostaglandins)

Question 20

what drug is used during labor and delivery to help induce AND augment contractions
- also helps limit post-partum bleeding

Answer 20

oxytocin

Question 21

what is the second choice for limiting post-partum bleeding?

Answer 21

ergot alkaloids

Question 22

what is the best tx for preeclampsia?

Answer 22

deliver that baby!

Question 23

what are the two most common obstetrical complications associated with preterm birth?

Answer 23

• spontaneous labor (45%)

- spontaneous rupture of membranes (35%)

Question 24

what is the trend that Wolff wants us to know about birth outcomes?

Answer 24

making it to term matters

- the later in gestational age, the better chance the baby has of surviving to 1 year

Question 25

what is the management of PPROM if > 34 weeks?

Answer 25

- GBS prophylaxis | - single corticosteroid course

Question 26

what is the management of PPROM if 32 - 34 weeks?

Answer 26

- GBS prophylaxis - single corticosteroid course - antimicrobials to prolong latency

Question 27

what is the management of PPROM if 24 - 32 weeks?

Answer 27

- GBS prophylaxis - single corticosteroid course - (no consensus on tocolytics) - antimicrobials to prolong latency - *MgSO4 for neuroprotection*

Question 28

what is the management of PPROM if <24 weeks?

Answer 28

- ***GBS prophylaxis NOT RECOMMENDED*** - single corticosteroid course - (no consensus on tocolytics)

Question 29

what heightens the risk of RDS?

Answer 29

preterm birth - affects 40-50% of babies born before 32 weeks - caused by surfactant deficit in immature lungs

Question 30

what drugs are used in pre-term delivery to promote lung maturation and increase surfactant production?

Answer 30

corticosteroids

Question 31

what are the indications for antenatal corticosteroids?

Answer 31

women between 24-36 weeks gestation with: - threatened preterm labor - antepartum hemorrhage - preterm rupture of membranes - conditions requiring c-section (preeclampsia, HELLP)

Question 32

fluorinated steroid that hastens fetal lung development | - given in TWO doses IM in 24hr intervals (48hrs total)

Answer 32

betamethasone

Question 33

fluorinated steroid that hastens fetal lung development | - given in FOUR doses IM in 12hr intervals (48hrs total)

Answer 33

dexamethasone

Question 34

what is the MOA of endogenous fetal cortisol?

Answer 34

induces transcription of surfactant proteins in alveolar type 2 pneumocytes

Question 35

why not administer cortisol to mom?

Answer 35

the placenta metabolizes/inactivates to CORTISONE (via *11b-hydroxy steroid dehydrogenase-2*), so it doesn't affect baby NOTE: this means you can give cortisol if mom needs it for something and it won't harm baby

Question 36

which drugs should you use to delay contractions?

Answer 36

currently NO FDA approved drugs in US... - nifedipine or indomethacin seem to be best choices currently available in US NOTE: recommendation is to NOT combine tocolytics

Question 37

calcium channel blocker - MOA: blocks calcium influx thru voltage-gated channels (less calcium=less contraction) - NOT FDA approved, but CCB's are preferable to other comparative tocolytics

Answer 37

nifedipine - causes flushing, headaches, dizziness - no fetal side effects

Question 38

what are the contraindications of nifedipine?

Answer 38

cardiac dz, maternal hypotension, avoid concomitant use with MgSO4

Question 39

prostaglandin synthesase inhibitor - MOA: blocks synthesis of PGFa2 (a potent stimulator of uterine contractions) - NOT FDA approved

Answer 39

indomethacin - causes nausea, heartburn, gastritis, proctitis, hematochezia, impaired renal function - fetal side effects: constrics ductus arteriosus, pulmonary HTN, reversable decrease in renal function with oligohydramnios

Question 40

what are the two main contraindication of indomethacin

Answer 40

significant renal or hepatic impairment

Question 41

which tocolytic has been found to delay labor for 2-7 days? - there is no evidence of benefit to fetus - mother experience side effects: cardiac arrhythmias, pulmonary edema, myocardial ischemia, hypotension, tachycardia, SOA, hyperglycemia, hyperinsulinemia, tremor, NV)

Answer 41

terbutaline (beta-2 agonist)

Question 42

what drug is used to prevent eclamptic seizures - MOA: inhibits ACh release at uterine NMJ - evidence does support its use for neuroprotection (appears to decrease risk for cerebral palsy) - is a long-term drug of choice for tocolysis in US (but rarely used elsewhere)

Answer 42

magnesium sulfate - in mom: causes skin flushing, palpitations, headaches, depressed reflexes, respiratory depression, impaired cardiac function - in baby: muscle relaxation, rarely CNS depression

Question 43

which b2-agonist used for tocolysis was approved by FDA in 1980, but was taken off the market in 1998?

Answer 43

ritodrine | - causes severe hallucinations

Question 44

oxytocin inhibitor what is NOT available in the US?

Answer 44

atosiban - causes maternal headaches, nausea - no fetal side effects

Question 45

synthetic PGE1 analog (similar to misoprostol) that **MAINTAINS a patent ductus arteriosus** - indicated in pre-term infants with congenital heart defects - infusion of PGE1 substitutes for and complements with PGE2

Answer 45

alprostadil | - adverse effects: hypotension, tachycardia, apnea

Question 46

what drugs can be used to CLOSE a ductus arteriosus? | - signs of a PDA: baby isn’t eating well, is listless, breathes too fast and seems to be sweating too much

Answer 46

NSAIDs! - indoemthacin - recently, more likely **ibuprofen**

Question 47

what drugs classes are contraindicated for HTN in pregnancy?

Answer 47

ALL ACE INHIBITORS/ARBs!!! | - they are lethal during 2nd/3rd trimesters

Question 48

what is the first line tx for moderate HTN in pregnancy?

Answer 48

- oral a-methyldopa (a2 agonist) | - oral labetalol (a/b blocker)

Question 49

what is the second line tx for severe HTN in pregnancy?

Answer 49

- parenteral labetalol - hydralazine (arterial vasodilator) - sodium nitroprusside (arterial/venous vasodilator)