High Risk Pregnancies Flashcards
Maternal condtions that signal a high risk pregnancy
Chronic HTN
Diabetes Mellitus
Obesity
Autoimmune conditions
Prior poor pregnancy outcomes
Preeclampsia/eclampsia
Post term pregnancy
RBC antigen sensitization
Renal disease
Seizure disorders
Vascular disease
Intrahepatic cholestasis Of pregnancy
Uterine malformations
Fetal conditions that signal a high risk pregnancy
Chromosome anomalies
Twin or greater pregnancies
Placenta previa, accreta and abruption
Antenatal testing and fetal surveillance
Purpose is to identify pregnancies at risk of hypoxic injury or death and to intervene before it gets to this point
This includes
- fetal kick counts (10 movements in 1 hr period 2x a day = golden zone)
- non stress test
- contraction stress test
- biophysical profile
- umbilical artery Doppler ultrasound
- estimation of fetal weight
- amniotic fetal assessment
Oligohydramnios
AFI (amniotic fluid index) < 5 cm and ADP <2cm
- all result in less than expected amnotic fluid
Rupture of membranes, placenta insufficiency, renal abnormalities are all possible etiologies
Treatment = amino infusion and treat underlying cause if determined
causes IUGR and potter sequence if not fixed (pulmonary hypoplasia, wrinkling of the skin, bilateral renal agenesis and PURs bilaterally, limb abnormalities)**
Polyhydramnios
AFI > 24 cm or SDP > 8cm
Causes are diabetes (most common), upper right GI abnormalities that impede swallowing or passing of fluid
- can be idiopathic
- rare but check for hemolysis of a newborn and TTTS*
Treatment = amino reduction to drain excess fluid and treat underlying cause
Non stress test
Measures the fetal heart rate patterns to determine overall health of the fetus
- measure all variables below and determines the “normals” of each variable
Observe
- baseline (normal = 110-160 bpm)
- variability (6-25 bpm from baseline is normal)
- accelerations ( 10 x 10 <32 weeks and 15 x 15 >32 weeks are normal benchmarks)
- decelerations
- (early (occurs at time of contractions) are associated with head compression and are good ,
- (variable (occurs at and not with time of contractions) are usually cord compression and can be pathological
- (late, are always delayed with timing of the contraction) are usually placental insufficiency and hypoxemia and is pathological and needs action)
- contractions
Contraction stress test
Similar to non stress except now adds oxytocin or nipple stimulation until 3 contractions occur in 10 minutes
Positive (abnormal) = late decelerations following > 50% of contractions
Negative (normal) = no late decelerations or varibale decelerations
Equivocal suspicious = intermittent late decelerations or significant variable decelerations
Equivocal tachysystolic = decelerations with contractions occurring more frequently every 2 minutes or lasting longer than 90 seconds
Unsatisfactory = fewer than 3 contractions in 10 minutes
Biophysical profile
Ultrasound of fetal well being assessment
10 points that include (each component is 2 points)
- non stress test (can be omitted)
- fetal movement
- fetal tone
- amniotic fluid assessment
- fetal breathing movements
if 10/10 or 8/8 = normal and risk of asphyxia in 1 week is near none
6/10 or 4/8 = equivocal and need to repeat in 24 hrs
- must have normal fluid level (if anhydramnios is present = -2 puts)
6/10-8/10 (4/8 or 6/8) = abnormal and risk of asphyxia in 1 week is 89/1000 births
(0-2-4)/10 = abnormal and risk of asphyxia in 1 week is 600/1000 (60%)
Umbilical artery Doppler ultrasound
Non invasive assessment of circulation and investigation of fetal hemodynamics
Most useful to assess pregnancies complicated by fetal growth restriction
Doppler waveforms need to be measured for
- presence
- direction
- profile
- volume
- impedance
Absent or reversed end diastolic flow velocity = placental insufficiency
Chronic HTN in pregnancy
Preexisting or HTN diagnosed before 20 weeks gestation
Management goals = get maternal BP < 150/100
- use BBs and CBB as needed as they are acceptable at this point (Labatalol and nifedipine as needed)
Preeclampsia
Mild:
- BP > 140/90 but < 160/110
- Proteinuria is < 300
- Patient is asymptomatic
- normal platlets and liver enzymes
Severe
- BP > 160/110
- proteinuria > 300
- patient is symptomatic
- thrombocytopenia or elevated liver enzymes ( if either of these two are present = automatic severe)
Management goals = monitor patient closely and try to maintain BP
- you will need to delivery early at 37-38 weeks for mild and severe = usually at diagnosis as long as they can
Also need to get labs for
- CBC, CMP and 24 hr urine protein every trimester
- 12 lead EKG
- multiple ultrasounds ever 4 weeks after 24 weeks
Magnesium sulfate OD in eclampsia
Loading dose should be 6-4 grams with 2 grams per hr ONLY for eclampsia
- prevents levels form getting above 5 mEq/Liter
5-10 mEq/L = EKG changes (prolonged PR and QT interval with widened QRS complexes)
10 mEq = areflexia
15 mEq/L = respiratory depression
> 25 = complete cardiovascular collapse
Pathophysiology assocaited with preeclampsia and eclampsia
Not 100% known but there are two potential thoughts
1) reduced placental perfusion possibly related to abnormal placental function.
- causes trophoblast invasion and inadequate remodeling of the uterine spinal arteries
2) maternal systemic manifestations with inflammatory metabolic and thrombotic responses which alter vascular function and result in multi-organ damage
Chronic maternal condtions that increases risk for preeclampsia and eclampsia
Chronic HTN
Diabetes mellitus (type 1 or 2)
Chronic kidney disease e
Auto-immune disease
Multiple gestation pregnancies
Chronic obesity
HELLP syndrome
Preeclampsia with hemolysis, elevated liver enzymes and low platelet counts
This immediately makes preeclampsia severe and requires immediate delivery once stable
