Ch 26 Assessment of High Risk Pregnancy

The use of ultrasounds has reduced risks previously assoc. w/ amniocentesis such as fetomaternal hemorrhage from a pierced placenta. Percutaneous umbilical blood sampling (PUBS) and Chorionic Villus Sampling (CVS) also are guided by ultrasonog. to accurately ident. the cord and the chorion frondosum

How are ultrasounds used adjunct to other invasive tests?

By 14 - 16 wks the placenta is clearly defined. At least 90% of placentas id earlier in pregnancy as previa or low lying ultimately resolve by third trimester. Placenta previa is diagnosed in 2nd trimester and ultrasounds should be preformed as pregnancy progresses. Many changes of the placenta are related to calcification, fibrosis or infarction.

How are ultrasounds valuable in diagnosing placental problems.

Needle is directly inserted into a fetal umbilical vessel, preferably the vein under ultrasound guidance. Small amount of blood is removed and tested immediately

How is PUBS performed?

AFV, vascular waveforms, heart motion, fetal breathing movements, fetal urine production and limb and head movements can be assessed

How is ultrasound used to monitor fetal wellbeing?

Early diagnosis which allows therapy to be started early in pregnancy, thereby decreasing severity and morbidity, both physical and emotional for family. This allows for families to make informed decisions about possible intrauterine intervention, termination, or preparing for care for infant w/ special needs

List all that ultrasounds provide for families.

Chronic hypertension, preeclampsia (w/ or w/out severe features), suspected or confirmed fetal growth restriction, multiple gestation, oligohydramnios, preterm prelabor rupture of membr., Later term or post term gestatation, previous stillbirth, decreased fetal movement, systemic lupus Erythem., renal disease, cholestasis of pregn.

List common maternal & fetal indications for antepartum testing.

1. Poor maternal weight gain or pattern of weight gain 2. previous pregnancy w/ intrauterine growth restict. 3. chronic infections 4. sustance use (Tobacco, alcohol, etc) 5. maternal diabetes 6. hypertension 7. multifetal pregn. 8. other medical or surgical complications

List some of the conditions that require ultrasound assessment of fetal growth

1. Low income 2. Lack of Prenatal Care 3. Age 4. Mature Mothers 5. Parity 6. Marital Status 7. Social Determinants 8. Ethnicity

List the Sociodemographic Factors of High Risks pregnancies.

1. head including ventricles & blood vessels 2. neck 3. spine 4. heart 5. stomach 6. small bowel 7. liver 8. kidneys 9. bladder 10 limbs (it detects normal anatomy and major fetal malformations)

List the anatomic structures depending on gestational age that can be id'd by ultrasound.

1. biophysical 2. psychosocial 3. sociodemographic 4. environmental

List the categories of risk.

1. Crown - rump in 1st trimester & biparietal diameter (BPD), head circumference, abdom. circumf., and femur length after 1st trimester

List the guideline measurements used to determine gestational age.

1. count once / day for 60 minutes 2. count fetal activity 2 or 3 times daily (after meals or before bed) for 2 hrs or until 10 movem. counted or 3. All fetal movements in a 12 hr pd each day until 10 movements are counted 4. Smart phone apps

List the ways to kick count

1. Mother - 35 years or older 2. Older Father - no consensus but 40 - 50 years old 3. Parent who are affected by or are carriers of genetic disorder including sickle cell, Tay Sachs, & Cystic Fibrosis 4. Women w/ prior child w/ a structural birth defect or with a structural fetal defect identified by ultrasound during current preg. 5. Women with prior child with chromosomal abnormality

List what puts families at high risk for a child with genetic disorders.

Traumatic injury or asphyxia during birth. Can be symmetric or asymmetric

Macrosomic infants are at increased risk for what. Are they characterized as symmetric or asymmetric?

Failure to diagnose and treat complications early is a major risk factor arising from financial barrier or lack of access to care, lack of understanding of the need for early & continued care, culture barriers and fear of healthcare system & providers

With regard to sociodemographic factors, how does lack of prenatal care affect pregnancies.

False - the organizations discourage it. Exposing the infant to high frequency soundwaves w/out clear medical indication should be avoided. Also in some facilities, non qualified people are performing the test and could give false reassurance to parents

T or F - 3 and 4 dimensional ultrasounds for nonmedical purposes is popular and safe so the AIUM and ACOG say its ok to do.

True - however, the measurement is still frequently preformed in clinical pracitce.

T or F - Accurate measurement of Amniotic Fluid Volume (AFV) using ultrasound is difficult and esidmates produced poorly predict abnormal values.

True - it should now be offered to all with the explanation of the tests and the risks involved

T or F - All pregnant women should be offered the option to screening and genetic testing regardless of age or other risk factors

Yes - it can be done at home, is non invasive, inexpensive and doesn't interfere with routine. Frequently used to monitor the fetus in complicated pregnancies that may affect fetal oxygenation

T or F - is the daily fetal movement count (DFMC or kick count) by moms a valuable tool?

Childbearing triggers physiologic, psychological and social suggest relations betw embryonal distress & birth complications. Risk factors include intrapsychic disturbances and addictive lifestyles, history of child abuse or partner violence, inadequate support systems, family disruption or dissolution, maternal role changes, noncompliance with cultural norms, unsafe cultural, ethnic or religious practices or situational crisis

What risks can psychologic status cause in a pregnancy?

low birth rate, higher neonatal mortality rate, increased rate of miscarriage, increased incidence of prelabor rupture of membranes. These risks are aggravated by low socioecon. status, poor nutri. & concurrent use of alcohol

What risks can smoke cause in a pregnancy?

Amniocentesis

What test is performed to obtain fluid which contains fetal cells, which is directed under ultrasonography, where a needle is inserted transabdominally into the uterus and fluid is drawn w/ a syringe after week 14

nuchal translucency screening (Fluid collection of greater than 3mm is considered abnormal

What test uses ultrasound measurement of fluid in the nape of the fetal back between 10 & 14 wks of gest. to id possible fetal abnormalities?

Doppler blood flow analysis

What uses systolic/diastolic flow ratios and resistance indices to estimate blood flow in various arteries?

They are performed when mom is suspected of carrying an anatomical or physiological abnormal fetus. Indications for this exam include abnormal history, lab findings or results from a standard or limited ultrasound. Highly trained and experienced personnel perform this test.

When are specialized/detailed/targeted ultrasounds performed and by whom?

6 wks and using transvaginal ultrasound. When fetus in good position, good views of fetal cardiac anatomy are possible in woman 13 wks gestation. Fetal death can be confirmed by lack of heart motion along with presence of fetal scalp edema and maceration and overlap of cranial bones.

When can fetal heart activity be demonstrated and how?

32 to 34 wks of gestation and cont regularly until birth

When does most monitoring begin in HR pregnancies

Absolute # has not been established other than in the situation in which fetal movements cease entirely for 12 hours (fetal alarm signal). A count of fewer than 3 movements w/in one hour warrents evalu. by non stress or a contraction test & a complete or modified biophysical profile.

When should one be concerned about low fetal movement counts

Possible increase of certain chromosomal abnormalities in fetus including trisomies 13, 18 and 21. An elevated NT alone indicates increased risk for congenital heart defects. If NT is abnormal, diagnostic genetic testing is recommended.

When the nuchal testing ids that the fluid collection is greater than 3mm and w/ abnormal maternal serum marker it can indicate what?

obstetricians, maternal/fetal medicine specialists, pediatric specialists, nurses, pharmacists, social workers, and dieticians

Who might be included in a team for high risk pregnancies?

To evaluate the fetal structure (CNS, thorax, abdomen, genr tract, musculoskeletal sys) and overall growth of the placenta and quantity of amniotic fluid.

Why would an MRI be used during pregnancy?

Women at both ends of child bearing age spectrum have an increase incidence of poor outcomes, however, age may not be a risk factor in all cases. Physiologic and psychologic risks should be evaluated

With regard to sociodemographic factors, how does age affect pregnancies.

Hypertensive disorders, pregestational diabetes, cyanotic heart dis., autoimmune dis., restictive pulmonay dis., multifetal gestation, malabsorp. disease/malnutri., living @ high altitude, tobacco/substance abuse

What are the risks assoc with intrauterine growth restriction (Maternal Causes)

Poorly controlled diabetes mellitus, fetomaternal hemorfhage, fetal congenital anomalies, genetic disorders, twin-to-twin syndrome

What are the risks assoc. with polyhydramnios?

Developing fetus may be affected adversely through several mechanisms. They can be teratogenic, cause metabolic disturb, produce chem. eff. or cause depression or alternation of CNS. Includes medications prescribed or OTC and commonly abused drugs including heroin, coke, and marijuana

What risks can drug use cause in a pregnancy?

Although used to diagnosis fetal defects in pregnancy, they are invasive and carry risks to the mother & Fetus. Induced abortion is linked with performing these test because there is no treatment for genetically affected fetus. THE FETAL RIGHTS IS AN ETHICAL CONCERN

What can be linked to the following: Amniocentesis, percutaneous umbilical blood sampling and chorionic villus sampling?

The components that are most predictive of perinatal outcome. It combines the NST w/ measurement of the quantity of amniotic fluid.

What does a modified biophysical profile assess?

It is a noninvasive dynamic assessment of the fetus of the physical and physiological characteristics of a developing fetus. It is based on acute and chronic markers of fetal disease. The BPP includes AFV, FBMs, fetal movements and fetal tone (Mostly used in late 2nd and 3rd trimesters)

What is a biophysical profile used in ultrasounds?

Because the life of the mother, fetus or newborn was jeopardized by circumstances coincidental w/ or unique to the pregnancy

What is considered high risk pregnancies?

reduced fetal growth

What is one of the most frequent conditions assoc w/ stillbirth?

Although some nurses have additional training/education to perform ultrasounds and BPPs, the main role is counseling and educating women about the procedure

What is the main role for nurses specific to ultrasounds?

Bleeding from the cord puncture. Transient fetal bradycardia can also occur and maternal complications are rare but include amnionitis and transplacental hemorrhage

What is the most common complication from PUBS?

Most common is evaluation of mosaic results found on amnio or CVS. It is also used to assess fetal anemia, infection & thrombocytopenia

What is the most common genetic indication for the use of PUBS?

chorionic villus sampling (CVS) - It cannot be used for maternal serum marker screening. It can be performed in the 1st or 2nd trimester ideally between 10 & 13 weeks & can be done transcervically or transabdominally

What is the popular technique for genetic studies in the first trimester?

Administering RhoD immune globulin to the mother who is Rh neg

What is the standard practice after an amniocentesis?

Decreased - oligohydramnios / Increased - polyhydramnios

Abnormalities in AFV are frequently assoc. with fetal disorders. What is decreased fluid call and what is increased fluid

Percutaneous Umbilical Blood Sampling (PUBS) however it has been replaced in many places with placental biopsy because it is safer, easier and faster.

What is the test that gives direct access to the fetal circulation during the 2nd & 3rd trimesters?

Usually not present during fetal sleep cycle, may be reduced temp. if woman taking depressant meds, drinking alcohol or smoking cig. THEY DO NOT DECREASE AS WOMAN NEARS TERM. Obesity decreases perception of movem & the ability of mother to count

What may decrease fetal movements?.

In reducing perinatal mortality and unnecessary obstetric interventions in fetuses w/ IUGR

Doppler ultrasound has been demonstrated to be of value for what?

30 w/ the mother being about to recognize about 70 - 80%

During the 3rd trimester, roughly how many body movements are made each hour?

It is when the head and body growth do not match. It suggests an acute or late occurring deprivation such as placental insuffic. resulting from hypertension, renal disease, or cardiovas. disease.

Explain asymmetric IUGR and its causes

Factors that originate w/in the mother or fetus & affect the development or functioning of either or both. (Examples genetic disorders, nutritional and general health status, medical or obstetric related illnesses)

Explain biophysical risk factors.

Factors include hazards in the work place and the woman's general environment and may include env. chemicals (lead, mercury), anesthetic gases, & radiation

Explain environmental factor risks

It is indicated for times of uncertainty regarding date of last menstrual cycle, recent discontinuation of oral contraceptives, bleeding episode during 1st trimester, uterine size that does not correlate w/ dates and other high risk conditions

Explain how and when ultrasonography is good for determining gestational age.

Consist of maternal behaviors and adverse life events that have a negative effect on the health of mom or fetus. May include emotional stress, history of depression or other mental health issues, disturbed interpersonal relationships such as intimate partner violence, substance use or abuse, inadequate social support, and unsafe cultural practices

Explain psychosocial risks

Arise from context in which the mom and family live. Risks may put mom or fetus at risk. Ex. Lack of prenatal care, low income, single marital status, being a member of an ethnic minority

Explain sociodemographic risks

The fetus is small in all parameters. It reflects a chronic or longstanding insult & may be caused by low genetic growth potential, intrauterine infection, chromosomal anomaly, maternal undernutrition or heavy smoking.

Explain symmetric IUGR and what is can be caused by.

Although exact effects of alcohol in preg. have not been quantified & its mode of action is largely unexplained, it exerts adv. eff. on the fetus, resulting in FAS, fetal alcohol effects, learning disabilities & hyperactivity

What risks can alcohol cause in a pregnancy?

Ultrasonography as it provides info regarding fetal activity, gestat. age, norm v. abnormal growth curves, fetal & placental anatomy, fetal well being & visual assistance with invasive tests.

Some consider what tool to be the most valuable diagnostic tool in obstetrics?

Complications of current or past pregnancies, obstetric related illnesses & pregn. losses put a woman @ risk

Specific to Biophysical Factors, explain the medical & obstetric disorders that can influence a pregnancy.

Smoking, Caffeine, Alcohol, Drugs, Psychological status

Specific to Psychosocial Factors, list the factors that complicate a pregnancy

Defective genes, transmissible inherited disorders and chromosomal anomalies, multiple pregnancy, large fetus size and ABO incompat.

Specific to biophysical factors, genetic factors may interfere with normal fetal or neonatal development, may result in congenital anomalies or create difficulties for the mom. What factors are included?

Adequate Nutrition young age, three pregnancies in the previous two years, tobacco, alcohol or drug use, inadequate nutrition intake because of chronic illness or food fads; inadequate or excessive weight gain and hematocrit value <33%

Specific to biophysical factors, what is one of the most important determinants of pregnancy outcome? Conditions that influence this are...

Birth defects in humans HAVE NOT been related to C. consumption. However, pregnant women who consume more than 200 mg of caff. daily (= to about 12 oz of coffee /day) may be increased risk for giving birth to infants w/ intrauterine growth restriction (IUGR)

What risks can caffeine cause in a pregnancy?

Because of the variability in fetal size thereafter

Ultrasound exam performed for pregnancy dating before 22 wks is comparable to one performed during 1st trim. in terms of accuracy. Why not after?

# of previous preg. is a risk factor assoc. w/ age & includes all first preg. espec. at either end of childbearing continuum. Incidence of preeclampsia & dystocia is increased w/ a 1st birth

What are some of the complications that come with parity?

anemia, preeclampsia, prolonged labor, & contracted pelvis and cephalopelvic disproportion lower educational attainment, lower income, increased dependence on govt. programs, higher divorce rates & higher parity

What are some of the complications that come with pregnant adolescents? What are long term implications?

Over 35 - not from age alone but also # and spacing of prev. pregnancies', genetic disposition of parents, med. history, lifestyle, nutrition & prenatal care. Increased likelihood of chronic diseases & complications that arise from more invasive medical mgt. of preg. & labor w/ combined demogr. charac. put older women @ risk. Conditions more likely exper. - Chronic hypertension & preeclampsia, diabetes, prolonged labor, cesarean birth, placenta previa, placental abruption, & death. Fetus at a greater risk of low birth weight, macrosomia, chromosomal abnormalities, congenital abnormal & neonatal death

What are some of the complications that come with pregnant mature mothers?

death, hemorrhage, infection, direct injury from needle

What are some of the complications to the fetus when performing amniocentesis?

leakage of amniotic fluid, hemorrhage, fetomaternal hemorrhage w/ possible Rh isoimmunization, infection, labor, placental abruption, inadvertent damage to intestines or bladder and amniotic fluid embolism

What are some of the complications to the mother when performing amniocentesis?

infection, radiations, chemicals, therapeutic drugs, illicit drugs, industrial pollutions, cigarette smoke, stress and diet. Also paternal exposure to mutagenic agents in the work place has been assoc. with an increased risk for miscarriage

What are some of the possible complications that are assoc. w/ environmental factors?

Increase in M&M rates for unmarried women including increased risk for preeclampsia, often related to inadequate prenatal care & young childbearing age

What are some of the possible complications that are assoc. w/ marital status?

Availability & quality of prenatal care. (ie women in metropolitan areas have more prenatal visits than women in rural settings & consequently higher incidence of maternal mortality) HC in inner city where residents are poorer & begin child bearing at a younger age & cont. longer may be lower quality than in for affluential areas

What are some of the possible complications that are assoc. w/ social determinates of health?

1. absent nasal bone 2. shortened femur or humerus 3. echogenic intracardiac focus 4. echogenic bowel 5. pyelectasis (enlargement of renal pelvis) 6. abnormally fast or slow fetal heart rate

What are some of the ultrasound findings that predict trisomy 21?

1. Id fetuses @ risk for injury caused by acute or chronic interruption of O so that permanent injury or death might be prevented 2. ID appropriate Oxygenated fetuses so that unnecessary intervention can be avoided.

What are the 2 major goals of antepartum testing in high risk pregnancies?

1. intrinsic growth potential and environmental factors

What are the 2 things that determine fetal growth?

1. Confirm pregnancy 2. Confirm viability 3. Determ. gestational age 4. Rule out ectopic pregn. 5. Detect multiple gestations 6. Determ. cause of vaginal bleeding 7. Visualization during chorionic villis sampling 8. Detect maternal abnormalities such as bicomuate uterus, ovarian cysts, fibroids

What are the major uses of ultrasonography during the 1st trimester?

1. Est. or confirm dates 2. Confirm viability 3. Detect polyhydramnios, oligohydramnios 4. Detect congenital anomolies 5. Detect intrauterine growth restrictions (IUGR) 6. Assess placental location 7. Visualization during amniocentesis 8. Eval. for preterm labor

What are the major uses of ultrasonography during the 2nd trimester?

1. Confirm gestational age 2. Confirm viability 3. Detect macrosomia 4. Detect congenital anomalies 5. Detect IUGR 6. Determine fetal position 7. Detect placental previa or placental abruption 8. Visualization during amniocentesis, external version 9. Biophysical profile 10. Amniotic fluid vol. assessment 11. Doppler flow studies 12. Detect placental maturity 13. Evaluate for preterm labor

What are the major uses of ultrasonography during the 3rd Trimester?

Advanced maternal age, Parental chromosomal rearrangements, Prev, Pregn. w/ autosomal trisomy, Abn. Ultrasound findings during current pregnancy (fetl structural anomalies IUGR, amniotic fluid vol. abnormal), Increased risk, as calcu. from noninvasive screening results (nuchal transluc & maternal serum analytes)

What are the related risks factors with Chromosomal Abnormalities?

Renal agenesis (Potter Synd), prelabor rupture of memb., prolonged pregn., uteroplacental insuff., severe intrauter. growth restr. (IUGR), maternal hypertensive disor, maternal dehydration/hypovolemia

What are the risks assoc with Oligohydramnios?

Genetic disorders, teratogenic exposure, fetal infection

What are the risks assoc with intrauterine growth restriction (Fetal Causes)