Obstetrical Complications (Wootton) Flashcards
Preterm Labor (PTL) definition
birth that occurs after 20 weeks but before 36 6/7 weeks
Diagnosis for preterm labor
- uterine contractions
- cervical change
- 2 cm and/or 80% effaced
What are the 4 main pathways for prevention of preterm labor?
- Infection (BV, GBS, gonorrhea/chlamydia)
- Placental-vascular
- Psychosocial stress and work strain (mental and physical stress)
- Uterine stretch (polyhydramnios - increased amniotic fluid and multiple gestations - twins)
The association between the cervix length and PTL
the relative risk for PTL is increased the shorter your cervix
** RR 6.2 for cervical length of 2.5 cm
Screening tools for preterm labor (PTL)
US and fetal fibronectin (FFN)
Evaluation for PTL
cervical exam to assess dilation, effacement and fetal presenting part; external monitoring and oral/IV hydration; cultures for group B strep
Hydration in PTL
hydration and rest will resolve uterine contractions but will NOT stop PTL
Management of PTL
if less than 34 weeks, start tocolysis:
Magnesium sufate - drug of choice
Nifedipine
Prostaglandin Synthetase Inhibitors`
Drug of choice for PTL management when less than 34 weeks
Magnesium sufate; competes with calcium for entry into the cell at the same time of depolarization; provides some neuroprotection (against cerebral palsy)
Nifedipine treatment in PTL
oral agent; inhibits/slows inward current of calcium during the second phase of the action potential
Agent used in extreme prematurity of PTL
Prostaglandin Synthetase Inhibitors; inhibits prostaglandin production that induce myometrial contractions; use on short term basis; can result in oligohydramnios
Agents for fetal lung maturation
glucocorticoids; effects last 7 days; single does of betamethasone is recommended for 34 - 36 weeks at risk for PTL within 7 days
What are the lower limits of viability of a preterm infant?
22 weeks or 500 g
Definition of premature rupture of membranes (PROM)
premature rupture of the membranes before the onset of labor at any gestational age
premature rupture of membranes (PROM) diagnosis
hx: loss of fluid and confirmation of amniotic fluid in vagina
**DO NOT check the cervix; will increase risk of infection!
rupture is confirmed using a sterile speculum
How is premature rupture of membranes (PROM) confirmed?
rupture is confirmed using a sterile speculum; AmniSure Test detects PAMG-I in amniotic fluid; can also confirm with pooling, nitrazine paper and ferning and an US
Why do you NOT check the cervix is you suspect a premature rupture of membranes?
will increase risk of infection!
What are some causes of false positives in nitrazine results?
urine, semen, cervical mucous, blood, vaginitis
What are some causes of false negatives in nitrazine results?
remote PROM with no remaining fluid or minimal leakage
What are the 4 things management of preterm prematurity rupture of membranes (PPROM) depend on?
- gestational age
- amniotic fluid index
- fetal status
- maternal status
Most PPROM will deliver when?
at 34 weeks regardless of fetal lung maturity
Antibiotic therapy for PPROM
48 hours of IV Ampicillin and Erythromycin/Azithromycin followed by 5 days of Amoxil and Erythromycin
Use of steroids for PPROM
up to 34 weeks to reduce risk of respiratory distress syndrome (RDS)
Importance of surfactant
necessary for lung function by decreasing alveolar surface tension and keeping alveoli open
Intrauterine Growth Restriction (IUGR) definition
when the estimate fetal weight or abdominal circumference of a newborn is BELOW 10%
Small for gestational age (SGA definition
BIRTH WEIGHT at the lower extreme of normal birth weight distribution
What are the 3 main categories for causes of Intrauterine Growth Restriction (IUGR)?
- maternal - smoking, drugs, alcohol, poor nutrition, teratogen exposure
- placental - tiny vessels, decrease substrate transfer, decreased trophoblastic invasion
- fetal - TORCH, congenital anomalies, chromosomal abnormalities
Diagnosis of Intrauterine Growth Restriction (IUGR)?
fundal height (pubic bone to the top of the fundus) lags more than 3 cm behind the gestational age; then order an US
What is the goal of Intrauterine Growth Restriction (IUGR) management?
deliver before fetal compromise but after fetal lung maturity
What are the 5 components of the Biophysical Profile (BPP)
- non stress test (NST
- fetal breathing movements
- fetal movements
- fetal tone
- amniotic fluid volume
What should you monitor after birth of a ntrauterine Growth Restriction (IUGR) infant?
neonatal blood glucose (low hepatic glycogen stores) and respiratory status for RDS
Definition of post-term pregnancy
a pregnancy that continues past 42 weeks; perinatal mortality is 2 to 3 times higher
Postmaturity syndrome
related to aging and infarction of the placenta; loss of subcutaneous fat, long fingernails, dry and peeling skin and abundant hair
Intrauterine Fetal Demise (IUFD) definition
fetal death after 20 weeks gestation, but before the onset of labor; most cases are unknown
Diagnosis of Intrauterine Fetal Demise (IUFD)
patient complains of absence of fetal movements or if unable to detect on Doppler fetal heart tones confirm by US with lack of fetal activity and absence of fetal cardiac activity
