B8.018 Prework 1: High Risk Pregnancies Flashcards
specific pregnancy related concerns in obese gravidas
early screening for gestational diabetes or overt diabetes
sleep study to assess OSA
screen for pre-existing hypertension
how does pregnancy contribute to development of diabetes
human chorionic somatomammotropin (hCS) induces metabolic changes in the mother such as mobilization of fatty acids, insulin resistance, decreased glucose utilization, and increased availability of AAs
decreases maternal use of protein
who is at risk for diabetes in pregnancy?
obese
strong fam history of DM2
polycystic ovarian syndrome
diagnosis of overt diabetes
FPG = 126
A1C = 6.5%
random glucose = 200
adverse risks associated with diabetes in pregnancy
preeclampsia polyhydramnios macrosomia fetal organomegaly maternal and infant birth trauma perinatal mortality neonatal respiratory problems and metabolic complications (hypoglycemia, hyperbilirubinemia, hypocalcemia, polycythemia)
direct effect of diabetes on offspring
risk of any congenital anomaly increases
long term risks: obesity, metabolic syndrome, autism
2 step approach for GDM testing
1 hr GTT (50g)
-if >135, do the 3 hr GTT (100g)
-fasting >95, 1 hr >180, 2 hr >155, 3 hr >140
need 2/4 values to be abnormal to meet criteria for GDM
1 step approach for GDM testing
2 hr GTT (75g load)
-fasting >92, 1 hr > 180, 2 hr > 153
if any value is abnormal, patient meets criteria
what to do once a diagnosis of GDM is made?
patient undergoes nutritional counseling and is then asked to check their blood sugars
initially > dietary changes, if this doesn’t work patient may receive pharmacologic treatment
medical interventions for GDM
insulin > gold standard
metformin and glyburide considered to be safe, oral alternatives
mechanism of metformin
- decreases hepatic glucose production
- decreases intestinal absorption of glucose
- improves insulin sensitivity by increasing peripheral glucose uptake and utilization
metformin side effects
NO RISK of hypoglycemia
common adverse reactions: diarrhea, N/V, flatulence, indigestion, abdominal discomfort, anorexia, rash
mechanism of glyburide
stimulates the release of insulin from the pancreas
-dependent upon functioning beta cells in the pancreatic islets
side effects of glyburide
hypoglycemia, nausea, stomach pain, loss of appetite, rash
rarely: jaundice, confusion, weakness, easy bruising or bleeding
how to monitor fetal well being during GDM
non stress tests 2x weekly
biophysical profile weekly
non-stress test
fetal heart rate patterns measures for 20-30 min
pattern tells provider if the baby is getting adequate oxygenation from the placenta
biophysical profile
US assessment that includes documentation of how much the baby is moving, fetal muscle tone, diaphragmatic excursions observes, and the amt of amniotic fluid that is around the baby
if all are present in sufficient amounts: baby is getting adequate oxygenation
advanced maternal age
> 35 years
risks with AMA
aneuploidy early onset gestational diabetes gestational HTN/ preeclampsia preterm delivery stillbirth
what should be offered to all pregnant mothers who are AMA
- genetic screening for trisomy 21, 18, 13
- first trimester US at 11-14 weeks
- offer additional serologic screening vs. chorionic villous sampling/amniocentesis - first trimester/early second trimester screening for GDM
- detailed fetal anatomy scan around 20 wks
- fetal growth at 32 wks
AMA < 40
in absence of gestational diabetes, HTN disorders of pregnancy, fetal growth restriction, or evidence of impending placental insufficiency, routine prenatal care is sufficient until 39 wks
AMA > 40
initiate weekly surveillance 32-34 wks
why are pregnancies at risk of aneuploidy?
VERY RARELY does fam history have any role in risk for a cytogenetic error to occur
meiotic nondisjunction in 95% of cases
>90% the extra chromosome is from the mother
why offer aneuploidy screening?
risk assessment
balance consequences of having a child with the particular disorder against the risk of an invasive diagnostic test
prenatal mental preparation
pregnancy monitoring
recommendations for delivery at tertiary center
first trimester aneuploidy screening option
nuchal translucency
thicker = abnormal
what is cffDNA
cell free fetal DNA
can be isolated from maternal plasma
result of apoptosis of the placental syncytiotrophoblasts (technology relies on the premise that the fetus and placenta originate from a single, fertilized egg)
predictive value of cffDNA
NOT good in lower risk populations
carrier screening performed
CF and SMA offered to all
some ethnic specific
fragile X in those with personal or family history of premature ovarian failure, autism, intellectual dysfunction, movement disorders
delivery in AMA pregnancies
most deliver in 39th week
- increased risk of stillbirth after this
- low risk of neonatal morbidity/mortality at this GA
drugs given to premature infants to reduce risks of morbidity and mortality
corticosteroids
magnesium sulfate
which pregnant mothers are given corticosteroids?
patients expected to deliver prematurely (<37 wks GA)
function of steroids in premature birth
stimulate fetal lungs to develop type 1 and 2 pneumocytesand surfactant
decreased rates of newborn mortality
decrease intraventricullar hemorrhage, necrotizing enterocolitis, and infections
when can steroids have a positive impact on premature infants
after 22-23 wks GA
which steroids can be given in pregnancy
bethamethasone
dexamethasone
need to be fluorinated to cross the placenta
conditions where you should defer delivery for steroid benefit x 48 hrs
labor platelets <100K elevated LFTs HELLP fetal growth restriction oligohydramnios critically abnormal umbilical artery doppler indices new onset renal dysfunction or deteriorating renal function
when should you NOT delay delivery to give sterois
uncontrolled severe BPs eclampsia pulmonary edema GA < 23 wks placental abruption DIC non-reassuring fetal status intrapartum demise
use of magnesium sulfate in delivery
if administered within 24 hours of delivery, newborns have less incidence of cerebral palsy and lower rate of death
magnesium sulfate administration recommendation
any pregnancy that is threatened to delivery < 32 weeks GA
neuro morbidity decreases after 32 weeks
mechanism of magnesium sulfate
stabilization of cerebral circulation by stabilizing blood pressure and normalizing cerebral blood flow
prevention of excitation injury by stabilization of neuronal membranes and blockade of excitatory neurotransmitters
protection against oxidative injury
protection against inflammatory injury via anti-inflammatory effects
hypertensive disorders in pregnancy
preeclampsia/ eclampsia
chronic HTN
chronic HTN with superimposed preeclampsia
gestational HTN
chronic HTN (pre-existing)
documentation of systolic BP >140 or diastolic BP >90 on 2 separate occasions at least 4 hrs apart
PRIOR to 20 wks GA
or diagnosis prior to pregnancy altogether
preeclampsia
new onset HTN: systolic BP >140 or diastolic BP >90 on 2 separate occasions at least 4 hrs apart
AFTER 20 wks GA
+ proteinuria >300 in 24 hr urine collection
gestational HTN
same as preeclampsia but without proteinuria
eclampsia
new onset tonic-clonic seizures associated with new onset HTN
other findings in preeclampsia
proteinuria -not required, don't want to delay diagnosis new onset systemic findings: -thrombocytopenia (<100K) -doubling of LFTs -doubling of Cr > 1.1 mg/dL -cerebral/visual disturbances -pulmonary edema
preeclampsia with severe features
new onset HTN criteria plus any of the following:
- persistent severe BP >160/105
- thrombocytopenia
- doubling of LFTs
- doubling of Cr > 1.1 mg/dL
- cerebral/visual disturbances
- pulmonary edema
- HELLP
- GI symptoms
GI symptoms w preeclampsia w severe features
persistent mid-epigastric/RUQ pain
new onset n/v
severe indigestion
preeclampsia prevention
aspirin (81 mg)
to women w history of delivery prior to 34 wks due to preeclampsia or >1 pregnancy affected by preeclampsia
management of preeclampsia without severe features
2x weekly visits -BP, physical 2x weekly fetal surveillance 1x weekly assessment of LFTs and platelets serial fetal growth assessment umbilical artery velocimetry
anti-hypertensives safe for pregnancy
labetalol
procardia
hydralazine
started if persistent BP > 160/110
BP goals in preeclamptic pts
decrease by 10-20 mmHg
systolic 120-150
when should preeclampic pts be delivered
37-39 wks
if severe, no later than 34 weeks
role of magnesium sulfate in preeclampsia
prevents eclampsia
triggers cerebral vasodilation, thus reducing ischemia generated by cerebral vasospasm during an eclamptic event
when should magnesium sulfate be administered in preeclampsia
severe signs/symptoms OR is eclampsia has already occurred
cure for preeclampsia
DELIVERY
preterm labor
regular uterine contractions accompanied by a change in cervical dilation, effacement, or both
initial presentation with regular contractions and cervical dilation of at elast 2 cm
problem w preterm labor
mild irregular contractions are normal, so its hard to distinguish true labor (results in cervical change) from false labor (contractions that do not result in cervical change)
preterm premature rupture of membranes
premature rupture of the amniotic membrane anytime prior to 37 weeks gestational age
pathophys of preterm labor
activation of the maternal or fetal HPA axis associated with either maternal anxiety and depression or fetal stress
- inflammation or infection
- decidual hemorrhage
- pathological uterine distention
pathophys of PPROM
shearing forces created by uterine contractions
intraamniotic infection
risk factors for PTL and PPROM
history of PTL or PPROM UTI STI short cervical length 2nd and 3rd trimester bleeding low BMI low SES cig smoking illicit drug use
evaluation for suspected PTL/PPROM
maternal physical and vital assessment
external monitors that assess for contractions and fetal heart rate
sterile speculum exam
digital cervical exam (if no concern for ruptured membranes)
send urine culture
send swab of vagina/perirectal area to assess presence of GBS
sterile speculum exam in suspected PTL
assess dilation
assess for rupture of amniotic membranes
collect samples of vaginal secretions for STI testing
signs of PPROM on speculum exam
fluid pooling in vaginal vault
ferning: appearance of dried amniotic fluid on light microscopy
nitrazine test: detects pH, amniotic fluid is basic
management of PTL
antibiotics for GBS prophylaxis
steroids for fetal lung maturation (over 48 hrs)
IV fluids
meds to stop contractions
tocolytics
given for 48 hrs to allow the full effect of the steroids to take place for fetal benefit
tocolytic options
COX inhibitors (indomethacin) Ca2+ channel blockers (Nifedipin) B-agonists oxytocin receptor antagonists magnesium sulfate NO
COX inhibitors mechanism
reduce prostaglandin production by inhibition of both COX 1 and 2
concerns about use of COX inhibitors
after 32 wks, risk of premature closure of the fetal ductus arteriosus which can result in right heart failure in utero
when not to use COX inhibitors
dont use after 32 weeks or for >48 hours
Ca2+ channel blockers mechanism
block influx of Ca2+ through cell membrane and inhibit release of intracellular Ca2+ from sarcoplasmic reticulum
increase Ca2+ efflux from the cell
leads to myometrial relaxation
risks with Ca2+ channel blockers
no known fetal side effects but can lead to maternal side effects due to vasodilatory actions
- headache, nausea, hypotension
- should be avoided if mothers have a pre-load dependent cardiac lesion or are already hypotensive
antibiotic management of PPROM vs PTL
for PPROM give for 7 days
for PTL, stop when threat has ceased
why use prophylactic antibiotics in PTL and PPROM?
prolong latency and reduce risk of neonatal and maternal infection
antibiotics used in pregnancy
Macrolides: ureaplasmas and chlamydia
ampicillin and amoxicillin: GBS and many gram neg bacilli, some anaerobes
delivery timing in PPROM
> 34 wks GA
chorioamnionitis
intrauterine or intraamniotic infection
associated with maternal and newborn morbidity
diagnosis of chorioamnionitis
fever >39 deg C
OR
fever > 38 on 2 occasions 30 min apart PLUS
-fetal HR >160 for >10 min
-maternal WBC >15,000 w left shift
-purulent appearing fluid coming from the cervical os visualized by speculum exam
treatment of chorioamnionitis
DELIVER
