Ch. 10 - Assessment of High-Risk Pregnancy

Question 1

In the past risk factors were evaluated only from a medical standpoint today a more comprehensive approach to high risk pregnancy is used and the factors associated with high-risk childbearing are grouped into broad categories based on threats to health and pregnancy outcomes these categories are biophysical psychosocial socio-demographic and environmental
Biophysical risks
Psychosocial risks
Sociodemographic risks
Environmental risks

Answer 1

Assessment of risk factors

Question 2

examples include genetic disorders nutritional and general health status in medical or obstetric related illnesses
Factors that originate within the mother or fetus and affect the development or functioning of either one or both

Answer 2

Biophysical risks

Question 3

consist of maternal behaviors and adverse Lifestyles that have a negative effect on the health of mother or fetus
going to include emotional distress history of depression or other mental illness Disturbed interpersonal relationships such as intimate partner violence substance use or abuse inadequate social support unsafe cultural practices
Maternal behaviors and adverse lifestyle

Answer 3

Psychosocial risks

Question 4

for example lack of prenatal care low income single marital status and being a member of a minority ethnic group
Arise from the mother and her family

Answer 4

Sociodemographic risks

Question 5

hazards in the workplace and the woman’s General environment and they include environmental chemicals and acidic gases and radiation

Answer 5

Environmental risks

Question 6

Two goals:
Ultrasonography (transvaginal/abdominal)
Ultrasonography

Answer 6

Antepartum testing/biophysical assessment

Question 7

first is to identify fetuses at risk for injury due to interrupted oxygenation so that permanent injury or death may be prevented and the second is to identify appropriately oxygenated fetuses so that unnecessary intervention can be avoided and most cases this monitoring Begins by about 32 to 34 weeks and continues until birth
Identify fetuses at risk for injury caused by acute or chronic interruption of oxygen so permanent injury or death might be prevented
Identify appropriate oxygenated fetuses so unnecessary intervention can be avoided.

Answer 7

Two goals:

Question 8

Diagnostic Ultra sonography is an important safe technique in antepartum’s fetal surveillance it is considered by many to be the most valuable diagnostic tool used In Obstetrics it provides critical information to Health Care Providers regarding fetal activity and gestational age normal versus abnormal fetal growth curves fetal and placental Anatomy fetal well-being and visual assistants with which invasive tests can be performed more safely an ultrasound examination can be performed either abdominally or transvaginally
abdominal ultrasonography is more useful after the first trimester when the pregnant uterus becomes an abdominal organ during the procedure women must have a full bladder to displace the uterus upward to provide a better image of the fetus
transvaginal ultrasonography is a probe it’s inserted into the vagina that allows pelvic and not anatomic features to be evaluated in Greater detail and uterine pregnancy to be diagnosed earlier this however does not require a woman to have fully bladder; optimally used in the first trimester; can detect an ectopic pregnancy, monitor the developing embryo help identify abnormalities and help establish gestational age
Indications for use

Answer 8

Ultrasonography (transvaginal/abdominal)

Question 9

Fetal heart rate activity
Gestational age
Fetal growth
Fetal anatomy
Fetal genetic disorders
Placental position and function
Adjunct to other invasive tests

Answer 9

Indications for use

Question 10

we use ultrasonography to obtain information regarding the number size and location of gestational sac the presence or absence of fetal cardiac and body movements the presence or absence of uterine abnormalities or adenexal masses and pregnancy dating during the second and third trimesters ultrasonography is used to assess fetal viability number position gestational age growth pattern and anomalies amniotic fluid volume placental location and conditions presence of uterine fibroids are anomalies presence of Advent adnexal masses and cervical length activity can be demonstrated by about 6 weeks of gestation using transvaginal ultrasound

Answer 10

Fetal heart rate activity

Question 11

gestational age and gestational dating by ultrasonography is indicated for conditions such as uncertainty regarding the date of the last normal menstrual period recent discontinuation of oral contraceptives a bleeding episode during the first trimester uterine size it does not agree with dates and other high risk conditions gestational dating May best be done using ultrasound measurements after the first trimester

Answer 11

Gestational age

Question 12

Conditions are required ultrasound assessment of fetal growth include poor maternal weight gain or pattern of weight gain previous pregnancy with intrauterine growth restriction chronic infections ingestion of drugs maternal diabetes hypertension multi-fetal pregnancy and other medical or surgical complications

Answer 12

Fetal growth

Question 13

Fetal Anatomy anatomic structures that can be identified by ultrasonography include the following head neck spine heart stomach small bowel liver kidneys bladder and limbs the presence of an anomaly May influence the location of birth and so that’s why we use this for a fetal Anatomy and the method of Earth at that the plans are often made for fetus with the condition that will require immediate surgery to be born in or near a hospital able to provide that care other than a small community hospital

Answer 13

Fetal anatomy

Question 14

A prenatal screening technique called nupal translucency uses ultrasound measurement of fluid in the name of the fetal neck between 10 and 14 weeks of gestation to identify possible fetal abnormalities when combined with abnormal maternal serum marker levels elevated NT or nuclear translucency indicates a possible increased risk for certain chromosomal abnormalities in the fetus placental position and function

Answer 14

Fetal genetic disorders

Question 15

major advantages of ultrasound is its ability to diagnose serious problems related to placental location another use for ultrasound is assessment of placental appearance many changes observed in the placenta are related to calcification fibrosis and infarction so as far as position of the of the placenta

Answer 15

Placental position and function

Question 16

Use with other invasive tests so the safety of amniocentesis is increased when the positions of the fetus placenta umbilical cord and pockets of amniotic fluid can be identified accurately we use ultrasound to safely perform amniocentesis

Answer 16

Adjunct to other invasive tests

Question 17

One of the major advances in perinatal medicine is the ability to study blood flow non-invasively in the woman fetus and placenta using ultrasound
Fetal well-being
Nursing role

Answer 17

Ultrasonography

Question 18

Doppler blood flow analysis
Amniotic fluid volume
Biophysical profile (BPP)

Answer 18

Fetal well-being

Question 19

Doppler blood flow analysis uses systolic diastolic flow ratios and resistance and disease to estimate blood flow in various arteries therefore it provides an indication of fetal adaptation and Reserve Doppler ultrasound has been demonstrated to be a value and reducing perinatal mortality and unnecessary obstetric interventions

Answer 19

Doppler blood flow analysis

Question 20

Antioch volume accurate measurement of amniotic fluid volume using ultrasound is difficult and evidence indicates that the estimates produce poorly predictive normal values however it is still frequently used abnormalities and AFV are frequently associated with fetal disorders subjective determinants of all oligohydramus (decrease fluid include a fungal height that is small for gestational age and a fetus that is easily palpated increase or that is below the total AFV)
can be evaluated by a method in which the vertical depths of the largest pockets of amniotic fluid in all four quadrants surrounding the maternal umbilicus are totaled providing an amniotic fluid index an AFI of less than 5 cm indicates oligohydramus with an AFI of 25 cm or greater indicating polyhydramnios

Answer 20

Amniotic fluid volume

Question 21

Biophysical profile real-time ultrasound permit detailed assessment of the physical and physiologic characteristics of the developing fetus and cataloging of Normal and abnormal biophysical responses to stimuli the biophysical profile or BPP is a non-invasive Dynamic assessment of a fetus that is based on acute and chronic markers of fetal distress in other words it’s kind of like a physical exam for the fetus the BPP is used frequently in the late second and the third trimester for an apartment fetal testing because it is a reliable predictor of fetal well-being a BPP score of 8 or 10 with a normal AFV is considered normal

Answer 21

Biophysical profile (BPP)

Question 22

Counseling and education regarding the procedure
Number of nurses with additional training and education perform ultrasound scans and bpps in certain centers the main roles of nurses or counseling and educating women about the procedures a standard part of current prenatal care most women look forward to and enjoy their prenatal ultrasound

Answer 22

Nursing role

Question 23

Amniocentesis
Chorionic villus sampling (CVS)

Answer 23

Biochemical assessment

Question 24

Biochemical assessment that we do on the fetus and that’s called an amniocentesis you may or may not have heard of this before and amniocentesis is performed to obtain amniotic fluid which contains field cells under direct ultrasonographic visualization and needle is inserted trans abdominally into the uterus and amniotic fluid is withdrawn into a syringe amniocentesis is possible after week 14 of pregnancy when the uterus becomes an abdominal organ and sufficient amniotic fluid is available for testing indications
Indication for use
Maternal complications
Fetal complications

Answer 24

Amniocentesis

Question 25

Several different categories or considered to be at increased risk for having a child with a genetic disorder that would be those of older maternal age 35 and older older paternal age there’s no real consensus but usually that anywhere from 40 to 50 years of age parents who are affected by or carriers of genetic disorders like Sickle Cell women with the prior child with the structural birth or chromosomal defective
ACOG recommends that all women regardless of age or risk factor be offered genetic screening or diagnostic testing
Genetic concerns
Fetal maturity
Fetal hemolytic disease

Answer 25

Indication for use

Question 26

Women over 35 years old
Family history of chromosomal abnormalities

Answer 26

Genetic concerns

Question 27

L/S and S/A ratios
For feet lung maturity Layton pregnancy after assessment of fetal lung maturity is possible by examining amniotic fluid to determine something called an LS Ratio or for the presence of PG
using a test called LBC become the primary test for determining field along maturity lamellular bodies are surfactant containing particles secreted by type 2 pneumocytes the number of lamellular bodies found in the amniotic fluid increases with the onset of functional fetal pulmonary maturity the LBC compares favorably with ls ratio in the PG test and predicting fetal lung maturity

Answer 27

Fetal maturity

Question 28

the past amniocentesis was used for identification and follow-up of fetal hemolytic disease
now replaced serial amniocentesis clearly because Doppler is far less invasive and sticking in Needle into someone’s uterus - done on serial basis

Answer 28

Fetal hemolytic disease

Question 29

leakage of amniotic fluid hemorrhage Vito maternal Hemorrhage with possible maternal RH ISO immunization infection labor placental abruption inadvertent damage to the intestines are bladder and amniotic fluid embolism

Answer 29

Maternal complications

Question 30

death Hemorrhage infection and direct injury from the needle

Answer 30

Fetal complications

Question 31

Coreionic Villa sampling is another type of biochemical assessment the combined advantages of earlier diagnosis and rapid results made from CVS a popular technique for genetic studies in the first trimester indications for CVS are similar to those for amniocentesis all those CVS cannot be used for maternal serum marker screening because no fluid is obtained CVS performed in the second trimester carries no greater risk for pregnancy loss than amniocentesis and it’s considered equal to amniocentesis and diagnostic
CVS performed the first or second trimester ideally between the 10 and 13th week of gestation and involves removal of a small tissue specimen from the fetal portion of the placenta
reflects the genetic makeup of the fetus
CVS procedures can be accomplished either transcervically or trans abdominally
this is a relatively safe procedure
pregnancy loss with CVS is similar to that of second trimester amniocentesis because CVS are invasive tests their uses associated with a small but concerning risk for pregnancy loss and infection
Earlier diagnosis and rapid results
Performed between 10 and 13 weeks of gestation
Removal of small tissue specimen from fetal portion of placenta
Chorionic villi originate in zygoteàTissue reflects genetic makeup of fetus

Answer 31

Chorionic villus sampling (CVS)

Question 32

Labs
Alpha-fetoprotein (AFP)
Multiple marker screens
Coombs’ test
Cell free DNA in maternal blood

Answer 32

Biochemical assessment: maternal assays

Question 33

these levels are used as a screening tool for neural tube defects and pregnancy through this technique approximately 80 to 85% of all open neural tube defects and abdominal open abdominal wall defects can be detected early screening is recommended for all pregnant women AFP is produced in the fetal gastrointestinal tract and liver and increasing levels are detectable in the serum of pregnant women from 14 to 34 weeks of gestation although antiotic fluid AFP measurement is diagnostic for neural tube defect maternal serum alphaeta protein is a Serum is a screening tool only it is not diagnostic
Protein screening can be performed with reasonable reliability anytime between 15 and 20 weeks of gestation once the maternal level of AFP is determined it is compared with normal values for each week of station
Maternal serum levels screened for neural tube defects (NTDs)
80% to 85% of open NTDs and abdominal wall defects can be detected early
Recommended for all pregnant women

Answer 33

Alpha-fetoprotein (AFP)

Question 34

Screens screening to detect fetal chromosomal abnormalities particularly trisomy 21 or down syndrome is available beginning at 11 to 14 weeks of gestation and the presence of a fetus with trisomy 21 HCG levels and a nuclear translucency measurement are higher than normal in the first trimester about 1/3 of all fetuses with an increased nuclear translucency having chromosomal abnormality and half of these trisomy 21 via assessment of the fetal nasal bone by ultrasound during the first trimester provides another way to predict trisomy 21 the nasal bone cannot be identified on ultrasound in about 1/4 to 1/3 of fetuses who have trisomy 21
Detects chromosomal abnormalities
PAPP-A, B-hCG, hCG markers associated with increased risk for trisomy 21 (Down’s)

Answer 34

Multiple marker screens

Question 35

indirect test with a screening tool for RH incompatibility however middle cerebral artery Doppler studies to determine the degree of fetal hemolysis have now replaced serial amniocentesis which we discussed earlier if a maternal title for RH antibodies is greater than 1.8 amniocentesis for determination of bilirubin and amniotic fluid is indicated to establish the severity of fetal hemolytic anemia
Rh incompatibility
Detects other antibodies for incompatibility with maternal antigens

Answer 35

Coombs’ test

Question 36

Self-dna screening is the newest screening test for aneuploiding and is performed also by a sample of maternal blood the cell free DNA test next is an example of a non-invasive prenatal testing and euploidy is defined as having one or more extra or missing chromosomes in the 23 pairs each individual normally possesses maternal plasma contains small fragments of cell-free DNA resulting from the breakdown of both maternal and fetal cells the test cannot actually distinguish fetal from maternal DNA but it can accurately predict the fetal status by measuring the amount of cell-free DNA circulating in maternal blood and comparing it with known standards women with positive CF DNA results are referred for amniocentesis or CVS to confirm findings
A new screening message for noninvasive prenatal genetic diagnosis
Works by amplifying cell free DNA

Answer 36

Cell free DNA in maternal blood

Question 37

Fetal Rh status
Fetal gender
Paternally transmitted single gene disorders

Answer 37

A new screening message for noninvasive prenatal genetic diagnosis

Question 38

identified somebody as being high risk
Goal
Nonstress test (fetal activity determination)
Vibroacoustic stimulation
Contraction stress test (CST)

Answer 38

Antepartal assessment using electronic fetal monitoring

Question 39

To determine if the intrauterine environment is supportive to the fetus
goal of third trimester testing is determine whether the entry unit environment continues to support the fetus the ability to detect and prevent impending fetal death depends on the group of prenatal women from pregnant women
selected for testing the predictive value test results as a first Line Screening test for feed a well-being and what I mean by that is a daily fetal movement count we teach women in the second trimester after we get through about 24 weeks how to do a daily fetal kick count: lay down your left side and just put your hands on your stomach and for two hours see if you can get ten movement; if you cannot get 10 movements in 2 hours call and do nonstress test

Answer 39

Goal

Question 40

applied technique for antepartum evaluation to fetus the basis for the non stress test is that the normal fetus produces characteristic heart rate patterns and response to feed a movement uterine contractions stimulation the most common reason for the absence of fetal heart rate acceleration is the quiet fetal sleep
CNS depressive medications chronic smoking in the presence of fetal malformation can also adversely affect the tests
comfortably seated at least; apply external fetal Monitor and contraction (Toco dynamometer)
usually completed in about 20 to 30 minutes so what we’re looking for is a normal Baseline modern variability and at least two accelerations in 20 minutes activity
Provider may manually stimulate the fetus or having the woman drink orange juice to increase your blood sugar level
if women are coming in for serial nsts because of identified them at high risk will often tell them before they come in to make sure that you have eaten or had something to drink we get a reactive strip within 20 to 30 minutes
sometimes it takes a little bit longer
Procedure
Interpretation

Answer 40

Nonstress test (fetal activity determination)

Question 41

Contraction stress test the contraction stress tests are oxytocin challenge test was the first widely used electronic fetal assessment test it’s purpose was to identify the jeopardized fetus that was a stable at rest but showed evidence of compromise after stress uterine contractions decrease uterine blood flow and placental perfusion if this decrease is sufficient to produce hypoxia in the fetus a deceleration the CST provides an earlier warning of fetal compromise in the NST and produces fewer false positive results
it’s more time consuming and expensive than the NST is also an invasive procedure as we have to start an IV administer oxidation typically to get the simulate contractions in general the CST cannot be performed on women who should not give birth vaginally at the time the test is done absolute contraindications for CST are preterm labor, placental previa, basal previa, cervical insufficiency, multiple gestation, previous classic incisions for C-sections
is generally used as a backup rather than the primary method for antipartum testing
Procedure
Interpretation
Provides a warning of fetal compromise earlier than NST

Answer 41

Contraction stress test (CST)

Question 42

Simulate the stress the fetus experiences in the first stage of labor
So the two message to the CST are nipple stimulation contraction test oxytocin stimulated contraction test
Nipple-stimulated contraction test
Oxytocin-stimulated contraction test

Answer 42

Procedure

Question 43

so the nipple the how this works is just how it sounds we have her massage one nipple for 10 minutes and then the there’s a couple different approaches to this usually this is going to take quite a while you either have got a woman who is really not on board with massaging her nipples
Do until three uterine contractions of modern intensity each lasting 40 to 60 seconds are observed in a 10 minute period and is 20 or 30 minutes procedure

Answer 43

Nipple-stimulated contraction test

Question 44

so we typically will jump right into starting an IV and slowly starting some pitocin to get those contractions going the oxytocinated contraction test one method of oxytocinfusion is to begin at half a milli unit and double the dose every 20 minutes until
Can take awhile to start reacting to it

Answer 44

Oxytocin-stimulated contraction test

Question 45

is a favorable reaction so the spikes that you see here on the bottom mama was probably moving or maybe she was hitting a button letting us know that she felt her baby move
accelerations in the heartbeat what makes this a reactive NST are the 2+ accelerations in a 20 minute period each lasting at least 15 seconds and peeking at least 15 beats above the baseline before 32 weeks however it acceleration has a little bit of a less stringent guideline: looking more for like 10 by 10s but after 32 weeks a 15x15 acceleration

Answer 45

Reactive NST

Question 46

not want to see with a third trimester pregnancy
if you had 20-30 minutes of nothing but this that would be considered non-reactive NST
many times just say wait longer or do fibro Acoustics simulation that’s what that is a test that is generally performed in conjunction with this NST and uses a combination of sound combination of sound and vibration to stimulate the fetus it’s kind of like it’s an instrument you put it up against the belly you hit a button and it creates a little bit of noise and then they go crazy
Concerning: took stimulator out and nothing happened and have an hour of this with zero reaction to a vibro acoustic simulator or maybe even a D cell a prolong diesel that this woman right here is going to end up getting a biophysical profile to look at other profiles to look at fetal well being

Answer 46

Non-Reactive NST

Question 47

And here are two examples negative CST this is what we want this is our desirable outcome right here is a negative CST CST results are negative positive equivocal suspicious or unsatisfactory those are our five categories if no late decelerations are observed with the contractions the findings are considered negative that’s what we want
the desired CST result is negative because it has consistently been associated with good fetal outcomes the likelihood of fetal death occurring within one week of a negative CST is less than one in a thousand

Answer 47

Negative CST

Question 48

repetitive late decelerations render the test results positive which we absolutely do not want
positive CST results have been associated with enter uterine fetal deaths, late fetal HR decelarations in labor, IUGR, and maconumium stained amniotic fluid

Answer 48

Positive CST