2 Articles - (Tocolytics/Inducers) NOT ON FOCUSED DRUG LIST

Question 1

Can tocolytics prevent preterm birth?

Answer 1

NO. They can only stop it for up to 48 hours, long enough to get a course of corticosteroid treatment in and get the mom to a facility with neonate care

Question 2

What is the most commonly used tocolytic agent int he US?

Answer 2

magnesium sulfate.

Question 3

MOA of magnesium sulfate?

Answer 3

magnesium is similar to Ca. It occupies the channels and reduces intracellular Ca concentrations, preventing myometrial contraction

Question 4

ADE of magnesium sulfate

Answer 4

contraindicated in myasthenia gravis and renal insufficiency.

Hypotension, pulmonary edema.
Decreases fetal HR.
May have fetal neuroprotective effects.

Question 5

MOA of nifedipine?

Answer 5

Ca channel blocker. decreases intracellular Ca leading to inhibitoin of acitn and myosin interaction, decreasing myometrial contractility.

Question 6

ADE of nifedipine

Answer 6

maternal peripheral vasodilation, compensatory tachycardia.
Stroke.
pulmonary edema, hypoxia, MI and atrial fib. Severe HYPOTENSION.
underperfused fetus

Question 7

MOA of indomethacin?

Answer 7

nonselective COX inhibitor. PGE normally forms gap junctions in myometrium that increase intracellular calcium and facilitate myometrial contractility. Indomethacin inhibits PGE production.

Question 8

ADE of indomethacin?

Answer 8

cardiovascular risks,

Premature closure of ductus arteriousus and oligohydramnios in fetus.

Question 9

What are the two main goals of tocolytic therapy?

Answer 9

to prevent delivery long enough to get a course of corticosteroid treatment in (promote lung development) and get the mom to a facility with neonate care

Question 10

Which tocolytic should be given to a mom <32 weeks gestation?

Answer 10

indomethacin because it is effective and has minimal side effects

Question 11

Which tocolytic should be given to a mom at 32-34 weeks?

Answer 11

nifedipine becuase it does not cary fetal risks of indomethacin (closure of ductus arteriosis and oligohydramnios)

Question 12

What are the risks of labor induction?

Answer 12

risk of cesarean, hemorrhage, infection, uterine rupture, neonatal respiratory distress, and iatrogenic prematurity

Question 13

What is the most important predictor of success of labor induction?

Answer 13

cervical ripening

Question 14

When should labor induction be considered?

Answer 14

pre-eclampsia, diabetes mellitus, premature rupture of membranes, choriamniotitis, IUGR, fetal demise.

Question 15

Most common complication of oxytocin labor induction?

Answer 15

uterine hyperstimulation.

Question 16

How do PGEs cause labor induction?

Answer 16

block progesterone and cause local infalmmatory response. Also PGE2 causes cervical ripening.

Question 17

What are ADEs of PGE labor induction?

Answer 17

abruption, intrapartum and postpartum hemorrhage, and fetal heart rate drops.

Question 18

What herbal methods are women using fo rlabor induction?

Answer 18

castor oil (most common)
blue (oxytoxic) and black cohosh (estrogenic effects).
They can interact with other inducers.