Tuesday, 2-28-Obstetrical complications (Wootton)

Question 1

preterm birth is defined as a birth that occurs after __ weeks but before __ completed weeks of gestation. Dx is uterine contractions with cervical change or cervical dilation of __ cm and/or __% effaced

Answer 1

after 20 wks

but before 37

cervical dilation of 2 cm

80% effaced

Question 2

Socioeconomic factors for PTL?

Medical and obstetrical factors for PTL?

Answer 2

AA’s 2x more likely as whites, decreased access to prenatal care, high stress, poor nutrition, genetic differences

previous hx of PTL, hx of 2nd tri abortion, repeated spontaneous 1st tri abortions, 1st tri bleeding, UTI/genital tract infx, multiple gestation, uterine anomalies, polyhydramnios, incompetent cervix

Question 3

the relative risk of PTL increases as cervical length ___

Answer 3

decreases

increasing use of US for routine screening of cervical length to assess risk

can also do fetal fibronectin for screening (NPV good, PPV low)

Question 4

symptoms of PTL?

Answer 4

mentrual-like cramping, low/dull backache, pelvic pressure, increase in discharge/bloody discharge and uterine contractions

Question 5

initial assessment of PTL?

Answer 5

cervical exam to assess dilation, effacement, and fetal presenting part

hydration and bed rest will resolve contractions in about 20% pts

also want to evaluate for any underlying correctable problems such as infx

Question 6

in management of PTL, what should you culture for?

Answer 6

Group B strep

also think about Ureaplasma, Mycoplasma, and Gardnerella as well as gonorrhea and chlamdyia

Question 7

in management of PTL, if there is no response to IV hydration and rest or diagnosed 2 cm and/or 80% effaced, then begin ___ (if gestational age <34 wks and no contraindication)

Answer 7

Tocolytics –> MgSO4, nifedipine, indomethacin

Question 8

drug of choice for PTL?

Answer 8

MgSO4

typically 6 gm LOAD IV then a 3 gm/hr continuous maintenance

Question 9

side effects (maternal) of MgSO4?

Answer 9

feeling of warmth and flushing
N/V
resp depression –> seen w/serum levels of 12-15 mg/dl
cardiac conduction defects and arrest at high serum levels

Question 10

side effects (neonate) of MgSO4?

Answer 10

loss of muscle tone
drowsiness
lower apgar scores

Question 11

this oral tocolytic is effective in suppressing PTL, has minimal maternal and fetal side effects, inhibits slow, inward current of Ca during 2nd phase of AP

Answer 11

nifedipine

Question 12

most common PG synthetase inhibitor used for PTL? potential complications?

Answer 12

Indomethacin (orally or rectally)

can result in: oligohydramnios (decrease fetal renal function), can cause premature closure of fetal ductus arterioles and result in pulm HTN and heart failure, infants exposed are at greater risk of necrotizing enterocolitis, intracranial hemorrhage

Question 13

___ are used for fetal lung maturation.

a single course of __ is recommended for pregnant women between 34 0/7 wks and 36 6/7 wks of gestation at risk of preterm birth within 7 days and who have not received a previous course

Answer 13

glucocorticoids

betamethasone

Question 14

the lower limit of viability of a preterm infant is __ weeks or __ gms

Answer 14

23-24 wks or 500 gms

Question 15

in labor and delivery of preterm infant, if vertex presentation then a _ delivery is preferred. if breech presentation then a __ delivery is preferred

Answer 15

vertex –> vaginal

breech –> c-section

Question 16

risk factors for premature rupture of membranes?

Answer 16

vag/cervical infx
abnormal membranes
incompetent cervix
nutritional deficiencies

Question 17

how do you dx premature rupture of membranes?

Answer 17

based on hx –> loss of fluid, confirmation of amniotic fluid in vagina

DO NOT CHECK CERVIX OF PRESUMED RUPTURED PRETERM PT. IT INCREASES RISK OF INFX ESP WITH THE PROLONGED LATENCY BEFORE DELIVERY

Rupture is confirmed using a STERILE SPECULUM

Question 18

tests for confirm premature rupture of membranes?

Answer 18

pooling
nitrazine paper (turns blue)
ferning

may also use US to evaluate amniotic fluid volume

Question 19

diagnosis of preterm premature rupture of membranes?

Answer 19

• maternal temp >100.4
• fetal or maternal tachycardia
• tender uterus
• foul smelling amniotic fluid/purulent discharge

Question 20

ACOG recommends abx usage for preterm premature rupture of membranes with:

Answer 20

48 hr course IV ampicillin and erythromycin/azithromycin followed by 5 days of Amoxil and Erythromycin

Question 21

what fetal lung substances are measured to test for fetal lung maturity and how are they obtained?

Answer 21

lecitin
phosphatidylinositol
phosphatidylglycerol

obtain by amniocentesis

Question 22

what lecithin/sphingomyelin ratio indicates mature lungs?

Answer 22

L/S ratio >2:1

Question 23

what test can be done rapidly for fetal lung maturity?

Answer 23

Lamellar body number density assessment (LBND)

Question 24

__ is defined by when the birth weight of a newborn is below the 10% for a given gestational age

Answer 24

intrauterine growth restriction (IUGR)

Question 25

methods of IUGR dx?

Answer 25

• Physical exam –> serial fundal height measurement is primary screening tool
• US –> biometry
• Direct studies (more for cause dx) –> amniocentesis, percutaneous umbilical blood sampling
• doppler studies

Question 26

if you do a fundal height and find that the height lags more than 3 cm behind the gestational age, then order a ___

Answer 26

ultrasound –> used routinely for high risk conditions that predispose to IUGR

Question 27

pre-pregnancy management of IUGR?

Antepartum management of IUGR?

Answer 27

pre: optimizing disease processes, i.e., blood sugar control in diabetes, control of HTN
ante: decrease any modifying factors-improve nutrition, stop smoking, bed rest

Question 28

goal of management of IUGR?

Answer 28

deliver before fetal compromise but after fetal lung maturity

Question 29

This test for monitoring IUGR is when the pt is in the lateral tilt position and the fetal heart rate is monitored with an external transducer. The tracing is observed for fetal heart rate accelerations that peak at least 15 beats per min above the baseline and last 15 secs from baseline to baseline. It may be necessary to continue the tracing for 40 mins or longer to take into account the variations of fetal sleep-wake cycle

Answer 29

Nonstress testing

For monitoring IUGR

Question 30

This test for monitoring IUGR consists of an non stress test with 4 observations made by real-time ultrasonogaphy. It has the following 5 components: Nonstress test, fetal breathing movements, fetal movement, fetal tone, and amniotic fluid volume

Answer 30

biophysical profile

for monitoring IUGR –> each component assigned a score up to 2. Composite score of 8-10 is normal, 6 is equivocal, 4 or less is abnormal

Question 31

in a doppler study of the umbilical artery, compare velocity diastolic flow through the artery in a normal to an IUGR:

Answer 31

umbilical flow velocity waveform of normally growing fetuses has high-velocity diastolic flow

IUGR has diminution of umbilical artery diastolic flow

Question 32

if you suspect IUGR and US shows IUGR and she is 38-39 weeks along, next step?

Answer 32

deliver

Question 33

if you suspect IURG and US shows IUGR and she is less than 38-39 weeks along, begin antenatal testing. If antenatal testing is normal, next step? If antenatal testing abnormal, next step?

Answer 33

normal –> continue pregnancy

abnormal –> deliver

Question 34

what is the definitions of post-term pregnancy?

Answer 34

pregnancy that continues past 42 weeks (~10% pregnancies)

Question 35

management of post term pregnancy?

Answer 35

induction of labor at 41 weeks is preferred plan of care

Question 36

__ is defined as fetal death after 20 weeks gestation but before the onset of labor (occurs in <1% pregnancies)

Answer 36

intrauterine fetal demise (IUFD)

Question 37

dx of IUFD? confirmation?

Answer 37

suspect if pt complains of absence of fetal movements or if unable to doppler fetal heart tones

confirm by US with lack of fetal activity and absence of fetal cardiac activity

Question 38

risks associated with post-term pregnancies?

Answer 38

fetal macrosomia (>4500 gms)
abnormal labor
shoulder dystocia
c-section

Question 39

management of IUFD?

Answer 39

• watchful expectancy
• induction of labor
• monitoring of coagulopathy

Question 40

why do you need to monitor for coaguloapathy in mom with IUFD?

Answer 40

pts with IUFD are at risk of DIC –> need to follow CBC, fibrinogen level, PT/PTT/INR

Question 41

list some causes to search for following an IUFD?

Answer 41

TORCH titers
parvovirus studies
listeria cultures
anticardiolipin Abs
hereditary thrombophilias
fetal chromosome studies
fetal autopsy