Guide & Evaluated by:Mrs. Amirtha Gowri.,M.Sc(N)Mrs.Vijayalaxmi.,M.Sc(N)Faculty of Nursing

Presented by: S.Anbuselvi

1st year M.Sc(N)

Biophysical Principles

Biophysical profile is a screening test for utero-placental insufficiency.

Fetal biophysical activities are initiated modulated and regulated through fetal nervous system

Biophysical tests Fetal movement count Cardiotocography Non-stress test Fetal biophysical profile Doppler ultrasound Vibro acoustic stimulation test Contraction stress test(CST)

Fetal Movement Count Two method

Cardif “count 10” formula:○ The fetal movement starting at 9.A.M, the counting

comes to an end as soon as 10 movements.○ Lessthan 10 movements- in 12hrs on 2 successive

days ○ No movements is perceived even after 12hrs in a

single day.

Daily Fetal Movement Count(DFMC) Three counts each of one hour duration(morning, noon

and evening) are recommended. The total counts are multiplied by 4 gives daily (12

hours). Kick – is lessthan 3 in each hour-indicates fetal

compromise. The count should be performed starting daily at 28

weeks of pregnancy. Maternal hypoglycaemia- associated with increased

fetal movement. Maternal perception of fetal movements may be

reduced with fetal sleep.

Non-Stress test

Continuous electronic monitoring of the fetal heart rate along with recording of fetal movement

Fetal heart rate acceleration with fetal movements – indicates healthy fetus.

Reactive- two or more acceleration morethan 15 beats per minute above the baseline and longer than 15 seconds- 20 minutes observation

Non-Reactive- absence of any fetal reactivity. The test to be started after 30 weeks twice weekly. Vibro Acoustic stimulation- assess the fetal sleep starts from quiet

to active sleep indicates a reactive fetus- harmless.

Fetal Biophysical Profile(BPP) Consists of NST and ultrasonographically determined amniotic fluid

index. BIO PHYSICAL SCORING

Parameters Minimal Normal Criteria Score

Non stress test Fetal Breating movment Gross body Movment Fetal Muscle Tone

Amniotic Fluid

INTERPRETATIONNo fetal Asphyxia Chronic Asphyxia Chronic Asphyxia Certain Asphyxia

Reactive PatternLepisode lasting> 30 Sec3 discrete body / Limb movments 1 episode of extension(Limb/ trunk)with return of flexion1 Pocket Measuring 2cm in 2 perpendicular planesMANAGEMENTAt weekly intervals>36 weeks deliver<30 weeks repeat testing in 4-6 Hrs≤ 120 min persistent score ≤ 4

222

2

2

8-10642

Fetal Cardiotocography(CTG) Two method

External – continuous tracing of FHRInternal – fetal ECG tracing is made by applying a

spiral pointed scalp electrode to the fetal scalp after rupturing the membrane.○ Intra uterine pressure could be simultaneously

measured by passing a catheter inside the uterine cavity.○ Advantages – can detect hypoxia ○ Drawbacks – trained personnel required .,instruments

are expensive

Interpretation of an intra partum Interpretation of an intra partum cardio tocographcardio tocograph

Character Normal Suspicious Abnormal

Baseline FHR

Baseline variability

Acceleration

Deceleration

110-150 BPM

10-25 bpm

2 in 20 min

None or early

<110 bpm or >150 bpm

<5 bpm for >40min

None in 40 min

Variable <60 bpm for <60 sec

>150 bpm or <110 bpm with decleration or variability < 5 bpm.

<5 bpm for >90 min or Sinusoidal pattern

None in 40 min

Variable >60 bpm for >60 sec or repetitive late deceleration or bradycardia > 3 min

Contraction Stress Test(CST) Asses fetal well-being during pregnancy where there is

alteration in FHR in response to uterine contractions. Indications:

Intrauterine growth restrictionPost maturityProcedure:

Oxytocin infusion is started –initial rate of infusion 1ml stepped up at the intervals of 20 minutes.

Using hand to palpate the hardening of the uterus during contracting auscultation of FHR/1 minute – 1 to 2 hours. To perform the test.

Interpretation of CST Positive – persistent late deceleration of FHR Negative – no late deceleration Suspicious – inconsistent Unsatisfactory – poor quality of recording. Hyperstimulation – deceleration of FHR with uterine

contraction lasting >90 seconds. Nipple stimulation test – rubbing the nipple through

her clothes for 10 minutes and it takes less time compared to CST.

Ultrasonography The audible range of frequency greater than 2MHz

(cycles per second). Sonar- “sound navigation and ranging” Introduced – Ian Donald – Glasgow- 1958. Methods

Through abdominal transducers – 3 to 5 MHz.Vaginal transducers – 5 to 7 MHz.B mode – brightness mode (2-D) images are obtained.M mode – to study the moving organs, a wave pattern in

the presence of motion eg. Fetal heart.

I.Trimester. Intrauterine Gastational Sac:

Yolk sac- 7000 mIU/ml Embryo – 11000mIU/mlGestational sac – eccentric in position within the

endometrium of fundusDouble decidua sign – decidua and the chorion which

appears as the two distinct layers of the wall of the gestation sac.

GS should increased by 1.1mm in diameter per day

Fetal anatomy and viabilityGestational age and fetal structures identified by Transvaginal

Sonography (TVS)

Menstrual age(weeks) Fetal Structures

4

567

8

9

Choriodecidual thickness, choronic sac.Gestation sac. Yolk sacFetal pole, cardiac activityLower limb buds, midgut herination(Physiological)

Upper limb buds, stomach

Spine, choroid plexus.

Nuchal translucency Increased fetal nuchal skin thickness >3mm by TVS –

strong marker for chromosomal anomalies.(Tri – 21,18,13)

Gastational age.The four methods of fetal age estimation

○ Determination of gestational sac dimension(at about 8 weeks)○ Measurement of crown-rump length(7 to 12 weeks)○ Measurement of biparietal diameter (after 12 weeks)○ Measurement of femur length (12 weeks)○ The average increase in the biparietal diameter beyond 34 weeks is

1.7mm per week○ When the HC/AC ratio is elevated (>1.0) after 34 weeks IUGR is

Suspected.○ A measurement of biparietal diameter of 9.8cm indicates maturity.

Mid Trimester Fetal Growth-is calculated on the basis of an

accurate gestational age and is expressed in percentiles – normal fetal weight should be between the 10th and 90th percentiles weight less than 10th percentile is considered small for gestational age(SGA) whereas more than 90th percentile is large for gestational age.

IndicationFetal viability, number, gestational ageAminiotic fluid volumePlacental location and maturity

Neural tube defects(NTD) Cranial abnormalities Anencephaly Choroid plexus cysts Spinal anomalies Fetal heart Fetal abdomen & abdominal wall Omphalocele Hydrops fetalis Fetal gender identification- detection of the testes within the

scrotum in the third trimester.

Placenta & umblical cord Placenta is a echogenic discoid mass Placental thickness at term about 30mm- more

than 45mm at any period of gestation- abnormal

Placenta of multifetal pregnancy:Dizygotic twins have always diamniotic, dichorionic

placenta(DiDi)-twin peak sign.

Third Trimester Estimated fetal weight is determined FL, AC

and BPD. Growth profile- IUGR- the HC is maintained but

the AC falls off around 30 weeks the HC:AC is therefore elevated.

Observation Chromosomal abnormality

Observation Chromosomal abnormality

a)Head •Choroid plexus cyst•Strawberry skull•Hydrocephalus•Holoprosencephalyb)Face •Cleft lip/palate

•Low set earsc)Nuchal translucency•>3mm

d)Heart•VSD, ASDe)Renal anomalies•Horseshoe kidney•Bilateral dilation-renal pelvis•Cystic dysplasia

Trisomy 18, 13, triploidy

Trisomy 13,18Meckel-Gruber syndromeTriploidy

Trisomy 21,18 ,13, Turner Syndrome

Trisomy 13,18, 21

Trisomy 13,18,21

Triploidy

f)Hands/feet•Flexed overlapping fingers•Rockerbottom/clubfoot•Polydactyly•Wide gap between 1st and 2nd toes•Clinodactyly •Short femur

g)G.I.System•Omphalocele•Duodenal atresia

h) General •Growth restriction•Hydrops

Trisomy 18Trisomy 13

Trisomy 21

Trisomy 13,18Trisomy 21

Trisomy 13,18,21Triploidy,45,XO

Doppler Doppler velocimetry of the umbilical artery.

The umbilical artery doppler waveform is to measure the peak systolic(s), peak diastolic(D) and mean(M) values from these values S/D ratio and the pulsatility index(P.I)[P.I=(S-D)/M] are calculated.

Normal pregnancy the S/D ratio and the pulsatility index decrease as the gestational age advances

In higher values S/D and P.I mean reduced diastolic velocities and increased placental vascular resistance(IUGR)

Continued.. Doppler velocimetry of the umbilical vein:

Normally umbilical venous flow is monophasicUmbilical venous pulsation are often associated with raised

CVP and cardiac failure and increased perinatal mortality.Reduced diastolic flow indicates high resistance in the

down stream vessel and low tissue perfusion. Presence of “notch” in the early diastole waveform also indicates high resistance to the flow.

Presence of notch in the uterine artery when confrimed bilaterally at 24 weeks indicates the possible development of pre-eclampsia & fetal growth restriction

Biochemical Maternal serum alpha feto protein(MSAP) Alfa feto protein is a oncofetal protein(Molecular Weight

70,000) MSAP level is elevated in a number of conditions 1. wrong gestational age

2. Open neural tube defects

3. IUFD

4. Anterior abdominal wall defects

5. Renal anomalies

Triple Test combined MSAFP, HCG and UE3(Unconjugated

Oestriol)It is used to detect Down’s Syndrome

ACETYL CHOLINE ESTERASE Amniotic fluid level is elevated in open neural tube

defects

Amniocentesis The deliberate puncture of the amniotic

fluid sac per abdomen Diagnostic – 14-16 weeks Genetic

disorders Therapeutic- Induction of Abortion by

instillation of chemicals in hypertonic saline

Chorionic villus sampling Performed for prenatal diagnosis of

genetic disorders Performed 10-12 weeks of gestation The removal of a small tissue specimen

from the fetal portions of the placenta

Percutaneous umbilical Blood sampling OR cordocentesis Fetal blood sampling and transfusion Usually done after 18 weeks gestation Values Haematological- Fetal anaemia Fetal Infection – Toxoplasmosis, viralinfections Fetal blood gas- Growth restrictions Fetal therapy – Blood transfusion, drug

therapy

Fetal pulmonary maturity Confirmation of lung maturation Assessment of severity of RH –iso

immunisation Bilirubin in the amniotic fluid by specto

phometric analysis