Obstetrics Flashcards
- Drug therapy for infertility
◦ clomiphene (Clomid)
‣ MOA: blocks estrogen receptors causing increased secretion of FSH and LH
‣ For: used to promote follicular maturation and ovulation in women with functioning pituitary and ovaries
‣ Admin: start 5 days after 1st day of your period
‣ A/E: menopausal - hot flashes, nausea, bloating, breast engorgement, visual changes, abdominal discomfort (rare, d/t ovarian hyperstimulation (edu!) => bloating / weight gain), multiple gestation risk (inform pt that risk is increased 10%)
‣ Monitoring: ultrasounds to count # of mature follicles (d/t ovarian hyperstimulation risk)
‣ Contraindications: pregnancy Category X
- Drugs that affect uterine function
- Beta 2 Adrenergic agonist
◦** terbutaline (Brethine)**
- Beta 2 Adrenergic agonist
◦ MOA: 1st line for suppressing uterine muscle activity (NOT for prevention of preterm labor);
◦ Admin: SQ or IV; cannot give > 4 doses bc hard on mom; hold for maternal HR > 120
‣ Before admin: VS of mom and baby, listen to lungs throughout admin
◦ A/E: cardiopulmonary issues
◦ Monitoring: watch for maternal - pulmonary edema, HoTN, tachycardia, hypokalemia, hyperglycemia; fetal - tachycardia, HoTN, metabolic abnormalities
- Drugs that affect uterine function
- ‣ Calcium channel blockers:
◦ nifedipine (Procardia)
◦ MOA: 2nd line (often given after terbutaline); blocks Ca channels in myometrium to suppress uterine contractions
◦ Admin: loading dose, used for 48 hrs
◦ A/E: safer than terbutaline (not as hard on mom); maternal - tachycardia, HoTN, hepatotoxicity; fetal - HoTN (fetal monitoring)
- Drugs that affect uterine function
- ‣ Cyclooxegenase inhibitors
◦ indomethacin (Indocin)
◦ MOA: suppresses prostaglandins => decreases contractions
◦ For: very premature babies bc less sensitive to A/E
◦ Admin: loading dose, given for 2-3 days
◦ A/E: maternal - nausea, gastric irritability, interstitial nephritis, rare postpartum bleeding;
‣ fetal - renal insufficiency, bronchopulmonary dysplasia, necrotizing enterocolitis, premature closure of ductus arteriosus (allows fetal respiratory fxn => leads to cardiopulmonary compromise), oligohydramnios (lack of amniotic fluid)
- Drugs that affect uterine function
- ‣ Protect preterm fetus
◦ magnesium sulfate
◦ MOA: inhibits the release of acetylcholine at neuromuscular junctions
◦ For: neuroprotective effect (protects baby from brain damage); does NOT stop preterm labor
‣ Also given for seizure prevention in moms with preeclampsia
◦ Admin: loading dose then infusion over 24 hrs (piggyback), or 1 single bolus
‣ VS every hour (respiratory depression), **intake and output **(no output = toxic), DTRs (for hyporeflexia), fetal heart tones and contraction pattern, serum Mg and kidney fxn Q4 hrs
◦ A/E: (Many and serious) maternal - initial rxn of flushing, HoTN, HA, dizziness, lethargy, feeling warm; later - depressed respirations, sleepiness, pulmonary edema
◦ Contraindications: myasthenia gravis, kidney impairment
‣ Fetal - muscle weakness (may require mechanical ventilation), hypotonia (decreased muscle tone), poor feeding
◦ Antidote: Ca gluconate
- Drugs that affect uterine function
- ‣ Prevent preterm labor
◦ hydroxyprogesterone caproate (Makena)
◦ MOA: causes uterine musculature to relax
◦ For: only drug approved by the FDA to prevent preterm labor from starting
‣ Only for: singeton pregnancy (one baby) with a hx of at least one preterm birth; not effective for all women
◦ Admin: IM Q7 days, SQ Q7 days, discontinue at 37 weeks gestation
◦ A/E: injection site rxn, thromboembolic events (rare), maternal - glucose intolerance, depression, fluid retention
◦ Monitor: pts with DM or depression hx
◦ Contraindications: uncontrolled HTN, liver cancer, liver disease, hx of thromboembolic events, cholestatic jaundice of pregnancy, undiagnosed vaginal bleeding, breast cancer
- Drugs that affect uterine function
- ◦ Labor and birth
- ‣ Step 1: Drugs for cervical ripening aka softening of cervix
◦ dinoprostone (Cervidil)
◦ MOA: synthetic prostaglandin E2 that breaks down collagen chains (for thinning) in cervix and sometimes can stimulate contractions (good)
◦ Admin:
‣ Prepidil - intracervically inserted gel, cannot be removed in tachysystole; after insertion lay supine for 30 min
‣ Cervidil (prefered) - vaginally inserted, can be removed immediately in tachysystole; after insertion lay supine for 2 hrs supine
‣ May give oxytocin afterwards (thinning and softening first, then opening)
◦ Monitoring: continuous uterine and fetal monitoring => uterine tachysystole can occur (too many contractions too close together) resulting in fetal distress
◦ A/E: N/V/D, fever
◦ Labor and birth
‣ Step 1: Drugs for cervical ripening aka softening of cervix
◦ Preventing postpartum hemorrhage
* * Drugs that affect uterine function ◦ misoprostol (Cytotec)
Step 1:
◦ MOA: (off label use) synthetic prostaglandin promotes cervical ripening and uterine contractions
‣ Works very fast
◦ For: cervical softening; also used for postpartum hemorrhage (causes fast contractions)
◦ Admin: Very small dose (25 mcg) in posterior fornix of vagina PRN Q4 hrs
‣ May give oxytocin afterwards
◦ Contraindications: hx of uterine surgery (**risk of uterine rupture **d/t strong uterine contractions)
◦ A/E: increased risk of uterine tachysystole (continuous monitoring)
Preventing PPH: * For: cause uterine contractions to stop bleeding, 1st line after oxytocin * Admin: rectal administration * A/E: **shivering, inc temp**
- Drugs that affect uterine function
- ◦ Labor and birth
- ‣ Step 2: Drugs used for induction or augmentation of labor
- ◦ Preventing postpartum hemorrhage
◦ oxytocin (Pitocin)
◦ *Induction: mom has not started labor so drug induces it; augmentation: mom’s body started labor but need it to go faster
Step 2:
◦ MOA: synthetic form of posterior pituitary hormone that stimulates frequency, duration, and force of uterine contrations (does not have hormonal effects as exogenous form)
‣ Used after cervix is soft already, and fetal lung maturity should be established
◦ Admin: IV in labor in order to control onset in microunits (small dose)
‣ Very dangerous drug to give: IV always use infusion pump and check rate frequently, run in very low dose regimen
‣ If uterine tachysystole or fetal distress occur => turn off drug !
◦ Monitoring: continuous fetal and uterine monitoring, frequent VS
◦ A/E: water retention, uterine tachysystole, uterine rupture, fetal disstress and hypoxia, increased pain with labor (need epidural or inc pain meds)
‣ Optimal contraction pattern: no more than 5 contractions lasting 1 min or less in a 10 min period, no increased uterine resting tone, normal fetal heart tones
◦ Contraindications: hx of uterine surgery, baby in distress
Preventing PPH: * For: cause massive uterine contractions to stop bleeding** (prevention or tx); 1st line** * Admin:** IM and / or IM in units (larger dose bc less risk after baby out) **given after delivery of the placenta * A/E: cramping, water retention
- Drugs that affect uterine function
- ‣ 2nd line drugs for PPH
◦ carboprost tromethamine (Hemabate)
◦ MOA: prostaglandin that causes uterine contraction and vasoconstriction
◦ Admin: IM, sometimes given same time as oxytocin
◦ A/E: N/V/D, fever, HTN, impaired respirations
◦ Contraindications: pelvic inflammatory disease, heart / liver / kidney / lung diseases
◦ Caution: HTN, asthma (NOT DOC), DM, uterine scarring
- Drugs that affect uterine function
◦ Methylergonovine
◦ Ergot (plant) derived, stimulates uterine contractions and vasoconstriction
◦ Admin: IM and /or PO (may get shot at Dr and oral at home)
◦ A/E: HTN (systemic vasoconstricture of vasculature => seizure), HTN-related HA, N/V
◦ Contraindications: women with HTN, liver / kidney disorders
Obsetrics Overview
◦ Fertility considerations: Are the correct hormones being released at the right lvls? At the right time? Are the structures functioning right?
◦ Menstrual cycle: FSH is released 1st in the first 14 days of cycle => FSH drops and stimulates thalamus to release large amounts of LH => causes ovulation to occur
‣ Hormones: estrogen, progesterone, FSH, LH
◦ Female infertility:
‣ Anovulation / failure of follicular maturation => not ovulating usually d/t no surge of LH or not ovulating at the right time
‣ Unfavorable cervicle mucous => not the right consistency, d/t hormones
‣ Hyperprolactinemia => can lessen estrogen production
‣ Endometriosis => structural problem (timing and hormone lvls may be correct); little pieces of the uterine lining escapes into the abdominal cavity, but remain hormonally active there
‣ Polycystic ovarian syndrome
◦ Male infertility:
‣ Hypogonadotropic hypogonadism (does not have enough testosterone / adrogens), erectile dysfunction, idiopathic
- Drugs that affect uterine function
◦ Preterm
‣ Overview
- Antepartum (before birth) meds: drugs given to stop uterine contractions to keep the baby in (usually only buys 24-48 hrs) => drugs given to mature baby’s lungs during that 24-48 hrs
‣ Protect preterm fetus
* Antibiotics
◦ For: treat bacterial vaginosis, yeast, UTI, STDs (any infection of the lower genital tract predisposes women to preterm labor)
◦ If mom is Group B Strep Positive (part of mom ‘s normal flora but can harm baby): give IV Penicillin (1st line) or Ampicillin (2nd line)
‣ IV 2 doses 4 hrs apart before labor starts
‣ *Group B can cause baby to be septic
‣ Protect preterm fetus
* Glucocorticoids
◦ For: promotes lung maturity (excellerates surfactant production)
◦ Give betamethasone IM or dexamethasone IM
