Obstetrics Flashcards
What must be present for diagnosis of Pre-term labor?
Contractions + Cervical Dilation from 20-36 weeks GA
Cervical incompetence = cervical dilation w/out contractions
Preterm contractions = contractions w/out cervical dilation
PROM = pt would have hx of “gush of fluid” from vagina (ROM without labor, PPROM is PROM
“Abortion” definition
Pregnancy that ends before 20 weeks gestation or a fetus less than 500 grams.
Chromosomal abnormalities account for 60-80% of these.
Preterm labor – when should you deliver vs. give tocolytics to prevent delivery?
Give tocolytics UNLESS 1 of the following:
- > 34 or >2,500 grams
- Maternal HTN
- Maternal Cardiac disease
- Cervical dilation > 4cm
- Maternal hemorrhage (abruptio placenta, DIC)
- Fetal death
- Chorioamnionitis
Preterm labor – at what fetus age &/or weight do you stop delivery vs. deliver?
Tocolytics if 600-2,500 grams OR 24-33 EGA.
Deliver if >2,500 grams or 34-37 EGA.
Preterm labor – if you need to stop delivery, what do you give?
Betamethasone to mature lungs (12g IM x 2 doses 24hrs apart)
+
Tocolytics: Magnesium sulfate, CCBs, or Terbutaline
**Betamethasone effects take 24 hours to work, peak at 48 hours, & last for 7 days.
What do you need to check when giving Magnesium Sulfate & why?
Check Deep Tendon Reflexes,
- because Mag sulfate can cause respiratory depression & cardiac arrest.
- Other SEs include headaches, flushing, diplopia, & fatigue.
Workup of suspected PROM?
Sterile speculum examination to confirm the fluid as amniotic fluid:
- fluid is present in posterior fornix
- fluid turns nitrazine paper blue
- fluid has ferning pattern when dry, under a microscope
PROM management
If + Chorioamnionitis:
– delivery now
If at term, w/out chorioamnionitis:
– wait 6-12 hrs for SVB, then induce labor if doesn’t occur
If preterm, w/out chorioamnionitis:
– Give Betamethasone + Tocolytics + ABX (ampicillin & azithromycin)
**do fewer exams to prevent chorioamnionitis
Placenta previa presentation?
- Painless vaginal bleeding
(vs. placental abruption, which has painFUL vaginal bleeding, usually in 3rd trimester)
- Painless vaginal bleeding
- Usually doesn’t cause bleeding until after 28 weeks
(although may be picked up on routine U/S before 28 wks)
Vaginal bleeding in 3rd trimester – next step?
Trans-abdominal ultrasound to see if placenta is lying in the uterus.
**DVE & transvaginal exam NOT done b/c they can separate the placenta from the uterus if placenta previa is present, causing further bleeding.
Placental abruption – what is it & what are some risk factors?
Premature separation of placenta from uterus, causing tearing of blood vessels & hemorrhaging into separated space.
Risk Factors:
- Maternal HTN
- Prior placental abruption
- Maternal cocaine use
- Maternal external trauma
- Maternal smoking during pregnancy
Polyhydramnios – causes?
- Intestinal atresia (duodenal)
- Tracheoesophageal fistula
- Maternal Diabetes (fetal polyuria)
- Anencephaly
- Werdnig Hoffman (can’t swallow; Congenital degeneration of anterior motor horn of the spinal cord, same region destroyed by polio virus infection)
Oligohydramnios – causes?
Prune belly: lack of abdominal muscles, so unable to bear down & pee
– Treatment = serial Foley cath placements
- Renal agenesis (incompatible w/ life; Potter Syndrome)
- Juvenile Polycystic Kidney Disease
- Fetal genitourinary obstruction
When is Prenatal antibody screening (for Rh-antibody) done for Rh-negative mothers?
Screened at initial visit, then it is done again @ 28 & 35 weeks
Management of Rh-negative mom with Rh-positive fetus?
Indirect antiglobulin test.
If positive for Rh-antibodies, then:
– Amniocentesis @ 16-20 weeks to evaluate fetal cells for Bilirubin levels
If low or medium, repeat amniocentesis in 2-3 wks or 1-2 wks, respectively.
If high bilirubin, to percutaneous umbilical blood sample to check fetal hematocrit & give intrauterine transfusion if low.
Treatment for pregnant patient w/ chronic HTN @ baseline?
Methyldopa, Labetalol, or Nifedipine
Gestational HTN definition?
BP over 140/90 that starts after 20 wks gestation.
There is no proteinuria & no edema.
**Treat only during pregnancy w/ Methyldopa, Labetalol, or Nifedipine