Fetal Assessment

Presented by:Ann Hearn, MSN, RNC

2013

Ultrasound

Definition -- an instrument which uses high frequency sound waves that deflect off of tissue and return as echoes to visualize structures in the body

Ultrasound

Advantages: Results are immediate Requires about 20 - 30 minutes Allows the mother and family to “see”

the baby NOW IN 3DDisadvantages: Expensive No Dx of inborn errors of metabolism

Ultrasound First Trimester (1-12 wks)Transvaginal US –procedureEmpty bladderLithotomy positionAssessment:Confirms pregnancy , viability & locationEstimates gestational ageIdentify fetal abnormalitiesAdjunct to chorionic villus sampling

Ultrasound 2nd & 3rd Trimester (13-40wks)Transabdominal USLeft tilt position with knees sl. BentFull bladder (2nd trimester)Assessment:Confirm viability, estimate gestational ageEvaluate anatomy and placental locationAssess growthEvaluate amniotic fluid volumeGuide for amniocentesis

Alpha - Fetoprotein (AFP) Measurement of protein produced by the

yolk sac and liver found in fetal plasma.

– Elevated AFP may indicate: Open neural tube defects Anterior abdominal wall defects Multiple gestation Advanced gestational age

– Low AFP associated with: Down syndrome (trisomy 21) Edwards syndrome (trisomy 18)

Chorionic Villus Sampling

(CVS) Invasive procedure Removal of small tissue specimen

from the fetal portion of the placenta Tissue obtained about 10 - 13

weeks gestation Detects chromosomal, metabolic &

DNA abnormalities

Trans-cervical Chorionic Villus Sampling

Chorionic Villus SamplingCVS

Risks:– Failure to obtain tissue– Rupture of amniotic membranes– Leakage of amniotic fluid– Vaginal bleeding – Intraurterine infection– Rh Alloimmunization– Maternal tissue contamination of the

specimen– Increased risk of spontaneous abortion

Chorionic Villus SamplingCVS

Nursing interventions– Monitor :

vital signs FHR uterine contractions/cramping vaginal discharge

– Administer Rhogam if indicated– Teach patient to report:

Uterine contractions Vaginal discharge S/S of infection

Amniocentesis

Aspiration of amniotic fluid by insertion of a needle through the abdominal and uterine wall into the amniotic sac

Amniocentesis

Purposes:2nd trimester

– Chromosomal abnormalities– Fetal Rh sensitization– Dx amnionitis– Confirm abnormal AFP (AFAFP)

3rd trimester– Fetal lung maturity

L/S ratio– Fetal hemolytic disease

Amniocentesis

An invasive procedure Requires a consent form to be signed Performed: 2nd trimester (between

15 20 wks gestation ) & during 3rd trimester.

Complications– Trauma– Infection – Hemorrhage– Preterm labor

Amniocentesis

Preparation– Vital Signs and FHT’s– Empty bladder– Abdominal prep and scrub– Ultrasound– Left tilt position

Area of insertion is anesthesized and a needle inserted into the amniotic cavity

15 - 20 cc of fluid withdrawn for analysis

Amniocentesis

Amniocentesis

Post care / Discharge Teaching– Monitor V/S, FHT’s and UC’s X 1 hour– Administer Rhogam if Rh negative– Observe for leakage of fluid from site– Teach patient to report –

Fetal hyperactivity or lack of fetal movement

Vaginal discharge: clear or bleeding Uterine contractions or abdominal pain Fever or chills

L/S Ratio Lecithin /Sphingomyelin

Ratio

Lecithin and Sphingomyelin are two components of Surfactant.

Assesses Fetal Lung Maturity

L/S Ratio Lecithin /Sphingomyelin Ratio

As surfactant increases in the fetal lungs, the levels of lecithin should also increase.

Lecithin becomes 2 - 3 times > sphingomyelin by about 35 weeks

Fetal maturity & adequate surfactant = L/S ratio > 2 : 1

Karyotyping

Determine sex of the fetus

Normalcy ofChromosomes

Karyotyping

Indications:– Maternal age 35 or > at time of birth (AMA)– Pervious child born with a chromosomal

abnormality– Mother carrying an X-linked disease– Parents carrying an inborn error of

metabolism– Both parents carrying an autosomal

recessive disease– Family history of neural tube defects

Karyotyping

Trisomy Monosomy

Antepartum Testing

Purpose– Determine fetal health or

compromise– Guide interventions– Reduce perinatal

morbidity/mortality

Non-Stress Test - NST

Assessment of fetal status Observation of fetal heart rate

associated with fetal movement. The FHR should increase or

accelerate with fetal movement FHR accelerations indicate an

intact CNS and adequate oxygenation

Procedure for an NST

Electronic fetal monitor is applied Fetal movements are documented Compare the FHR with the fetal

movements Results:

– Reactive -- at least two accelerations of FHR with fetal movement of 15 BPM, lasting 15 seconds or more, over 20 minutes.

– Nonreactive -- the reactive criteria are not met. Indication of need for further assessment

Non-Stress Test - Reactive

Contraction Stress Test – CST

A means of identifying the fetus that is at risk for intrauterine asphyxia. Determines utero-placental insufficiency.

Procedure for an CST Electronic fetal monitor attached IV Oxytocin (low dose) –or- Nipple stimulation started Goal -- 3 contractions of good

quality, lasting 40-60 seconds over a 10 minute period

Contraction Stress Test - CST Results:

– Negative -- 3 contractions in 10 minutes with NO signs of late decelerations

– Positive -- repetitive persistent late decelerations occurring with more than half the contractions

– Equivocal – FHR decelerations with uterine hyperstimulation

– Unsatisfactory – fewer than 3 contractions in 10 minutes

Positive CST

Contraction Stress Test

Post CST Monitoring– FHR– Labor– SROM

Discharge instructions– Notify HCP for the following:

Regular painful contractions Leakage of amniotic fluid Decrease or increase in fetal movement Vaginal bleeding

Fetal Assessment

Non-Stress Test Reactive

Non - ReactiveRepeat in 1 - 2 weeks Reactive Stimulate

Non- Reactive

Contraction Stress Test

Negative Positive

Further Evaluation

Repeat NST in 1 week Possible Delivery

Try This!

Which of the following is NOT an indication of fetal distress?A. A reactive non-stress testB. Non-reactive non-stress testC. A positive CSTD. A negative CST

Biophysical Profile

Comprehensive assessment of five biophysical variables:

1. Fetal breathing movement2. Fetal movements of body or limbs3. Fetal tone (extension and flexion of

extremities)4. Amniotic fluid volume – visualized as

pockets around the fetus5. Reactive FHR with activitity (reactive NST)

Biophysical Profile

By combining these five assessments, the BPP helps to

identify the compromised fetus and to confirm the

healthy fetus

Since it combines several assessments, it is a better

indicator of fetal well-being

Biophysical Profile

A score of 0 or 2 is assigned to each finding for a maximum score of 10.

Scores of 8-10 are considered normal

Lower scores are associated with a compromised fetus and warrant further assessment and possible delivery of the fetus.

BiophysicalVariable

Normal(Score = 2)

Abnormal(Score = 0)

Fetal breathing movements

1 or more episodes of >20 s within 30 min

Absent or no episode of >20 s within 30 min

Gross body movements

2 or more discrete body/ limb movements within 30 min (episodes of active continuous movement considered as a single movement)

<2 episodes of body/limb movements within 30 min

Fetal tone 1 or more episodes of active extension with return to flexion of fetal limb(s) or trunk (opening and closing of hand considered normal tone)

Slow extension with return to partial flexion, movement of limb in full extension, absent fetal movement, or partially open fetal hand

Reactive FHR

2 or more episodes of acceleration of >15 bmp* and of >15 s associated with fetal movement within 20 min

1 or more episodes of acceleration of fetal heart rate or acceleration of <15 bmp within 20 min

Qualitative AFV

1 or more pockets of fluid measuring >2 cm in vertical axis

Either no pockets or largest pocket <2 cm in vertical axis

Fetal Movement: Kick Counts

Non-invasive Goal:

– 10 kicks in 12 hours – 2-3 times/day – at least 3 movements

in 60 minutes

The End

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