Ch. 16 Fetal Well being assessment PDF

Preview

Summary

Concepts from chapter 16 Fetal well-being assessments from Old's Maternal Newborn Nursing 11th edition ...

Description

Assessment of fetal well-being Ch. 16 Severe maternal morbidity = maternal morbidity + physical and psychologic conditions causing adverse effects during the pregnancy

Psychologic Reactions to Antenatal testing   

Maternal anxiety and fear Provide clear, concise explanations of possible results and management options after Ultrasound in the 2nd and 3rd semester helps to Identify: o multiple gestation o gestational age o fetal anomalies o placental disorders o maternal structural abnormalities o fetal well-being o amniotic fluid volume o fetal presentation and position

Nursing management Encourage the family to ask questions and voice concerns present easy to understand information provide follow-up care interpret results arrange for additional testing answer questions support the woman and her family

Assessment     

History of the present prenatal course identify possible indications for a particular diagnostic test understanding of the indication for testing the test itself presence of any psycho sociocultural factors that may influence teaching or learning process

   

Readiness for the enhanced knowledge Fear risk for impaired attachment anxiety

Dx

Planning and Implement   

Provide needed and desired information about the screening or diagnostic tests be an advocate for the expected woman provide information about the procedure and follow up monitoring

Assessment of fetal well-being Ch. 16  

Establish a trusting relationship to increase the possibility of free talking concern sharing approach each encounter with calmness, compassion, and honesty

Evaluation  

Evaluate the understanding of the antepartum testing procedures by the woman and family the teaching methods were used effectively for the family

Fetal Heart Rate  Baseline: 110-160 bpm  Tachycardia > 160 bpm (maternal fever, hypoxia, anemia, prematurity)  Bradycardia < 110 or 120 bpm (asphyxia, drugs, arrhythmia) Ultrasound       

Diagnostic procedure that uses high frequency sound waves to produce an image Very dense or bone = white Soft tissue = gray Fluid = black sonogram ultrasounds = produce images internal monitoring – MEMBRANES MUST BE RUPTURED External monitoring o Tocodynameter and transducer o transducer = device to turn the sound waves into electrical signals

Extent of exams 





Limited ultrasound examination = to address a specific question o determine specific information o determine future presentation before or during labor o evaluate cervix o guide amniocentesis o presence of gestational sac o embryo development standard ultrasound examination = during 2nd or 3rd trimester o fetal presentation o fetal number o amniotic fluid volume o placental position o cardiac activity o fetal biometry o anatomic survey specialized ultrasound = anomaly suspected o fetal doppler

Assessment of fetal well-being Ch. 16 o o o o

BPP Fetal EKG Amniotic fluid assessment Biometric studies

Methods of scanning 



Transabdominal o Prepare- drink 1 – 1.5 quarts of water 2 hours before and not empty bladder o Gel over abdomen o Semi-fowler o Vaginal, cervix, and bladder visualized o Amniocentesis and routine assessment Transvaginal o Vaginal insertion with gel over instrument o Lithotomy with butt at end of table o CVS, cervical length, and cervical funneling

Indications 

Use of obstetric ultrasound to obtain o Estimation of gestational age o Evaluation of abnormalities o Determination of fetal presentation o Multiple gestation o Uterine size and clinical date o Adjust to special procedures o Fetal death o Screening

Assessment 1st trimester Viability  

Potential for the pregnancy to result in a live neonate most common symptoms to do an ultrasound = bleeding, previous fetal loss, unknown last menstrual period, dating and size discrepancy

Beta HCG testing     

beta human chorionic gonadotropin Product of the trophoblast or placenta accurate marker of the presence of pregnancy and placental health detectable in the blood serum by 8 - 11 days evaluation done if: o history of spontaneous abortion o history of ectopic pregnancy o risk of ectopic pregnancy

Assessment of fetal well-being Ch. 16 o o

vaginal bleeding conception through assisted reproductive methods

Progesterone level testing   

Secreted early in pregnancy by the corpus luteum Low levels = spontaneous abortions or ectopic pregnancies Treated by giving the woman progesterone orally or via vaginal suppository or intramuscular injection

gestational age 



  

Traditional means of establishing in EDB o reliable last measure period o Measuring uterine size o Noting the date of the first audible fetal heart tones o Noting the date of quickening When dating a pregnancy with ultrasound o crown rump length accurate for six to 12 weeks gestation plus or minus three to five days o after 12 weeks gestation o femur length o abdominal circumference biparietal diameter are the most accurate markers for dating 7 to 14 days after 26 weeks = ultrasound inappropriate to determining gestational age 3rd trimester ultrasound estimate EDB with plus or minus 14 to 21 days of accuracy

Genetic screening options 





1st trimester single screen test include: o nuchal translucency measurement o serum beta HCG or total HCG o pregnancy associated plasma protein A analyte levels o perform between 11 weeks and 0 days and 13 weeks and 6 days o determine if it is at risk for chromosome disorder o assess the accumulation of fluid in the nuchal fold cell free DNA testing = noninvasive maternal serum blood tests that extract fetal DNA from maternal circulation after 10 weeks o 98% detection rate for fetal trisomy 21 o lower detection rates for trisomies 13 and 18 o determine fetal sex o presence of a RH positive fetus in a RH negative mother o detect paternally arrived autosomal dominant genetic abnormalities abnormal test result = genetic counseling and offered CVS or amniocentesis

Assessment of fetal well-being Ch. 16 Assessment 2nd trimester   



Integrated test = 1st trimester tests plus quadruple screen Quadruple screen = measures AFP, uE3, beta HCG for risk of having affected fetus Contingent screening = based on or congruent to 1st trimester results o If 1st trimester results negative = no testing o If 1st trimester results positive = diagnostic testing Stepwise screening = woman at higher risk for affected fetus after 1st trimester screening for diagnostic testing or cfDNA o Abnormal = continue invasive procedures

Ultrasonographic screening   



EGA Fetal anatomy Standard 2nd trimester sonogram includes o Fetal  Life  Number  Presentation  Abnormal heart tones  Fetal anatomy  Age and growth  AFV  Placenta location  Umbilical cord  Uterine anatomy Multiple gestations need to be assessed for o Chronicity o Amnionicity o Size comparison o Fetal genitalia o Amniotic fluid in both membranes

Fetal Life   

Presence of cardiac motion Fetal heart tones with ultrasound or doppler Absence of fetal heart tone = fetal demise

Fetal Number 

Identify multiple gestations or number of fetuses in the uterus

Fetal presentation 

Can be obtained but has no clinical significance

Fetal anatomy survey

Assessment of fetal well-being Ch. 16   

 

Head- skull should be symmetrical; choroids should be symmetrical; the nuchal folds need to be assessed; skull is brightly echogenic and easily visible Spine- examined for presence of sac or an outward splaying of the vertebrae laminae Thorax and heart- examination for size, shape, and symmetry of thorax and of heart including the axis; lungs should have homogenous appearance; diaphragm should be imaged Abdomen- bladder, stomach, and kidneys should be visualized; fetal stomach and bladder can be seen Extremities- femur is the only bone measured for abnormality

Gestational age and growth 

Hadlock method for average measures of the biparietal diameter, head circumference, abdominal circumference, femur length for gestational age

Amniotic fluid volume  

Subjective assessment of amniotic fluid volume as decreased, normal or increased Amniotic fluid index also used to calculate

Placenta Location 

Appearance, location, relationship to cervical os should be examined for complications

Survey of uterine atony  

Assessed for maternal anatomy and for any abnormalities or defects Uterine myomas or fibroids are common, and most be noted and monitored

Assessment 3rd trimester Conditions for fetal surveillance Maternal complications       

HTN DM Renal disease Heart disease Lupus Hyperthyroidism Blood disorders

Prenatal complications    

PIH Decrease fetal movement AFVolume abnormalities IUGR

Assessment of fetal well-being Ch. 16   

Multiple gestation Previous complications Abnormal test results

Fetal movement assessment 



Fetal movement count- noninvasive method of fetal surveillance o Monitored daily by pregnant woman at 28 weeks o Feel movements at least 10x in 12 hrs Daily fetal movement record- mother lies on side and counts the number of movements until she reaches 3 movements in 1 hr o Vigorous fetal movements provides reassurance of fetal well being o Call HCP if concerned of decrease in fetal movement from norm o After 28 wks if lower than expected = further fetal surveillance

Nonstress test    







external electronic fetal monitor to obtain tracing of FHR Based on knowledge that fetus is normally active during pregnancy Accelerations = active central and autonomic nervous system that is not being affected by intrauterine hypoxemia Advantages include o Quick and easy to perform o inexpensive easy to interpret o performed in an outpatient setting o no known side effects Disadvantages include o Difficult to obtain suitable tracing o results influence by fetal sleep cycle o monitoring extension may be required o maternal obesity, excessive fetal movement, hydramnios, and other factors can make the test difficult to perform The Acme of acceleration = 15 bpm or more above the baseline rate o Accelerations last 15 seconds or longer < 2 minutes in fetuses at or beyond 32 weeks o There must be at least two accelerations within a 2 minute. o Before 32 weeks = acme of 10 beats per minute or more for 10 seconds or longer useful in pregnant women with complications and conditions

Procedure for performing NST   

eat prior to the test and abstain from cigarette smoking for at least 2 hours before to the exam placed in semi Fowler position with a small pillow or blanket under the right hip to move the uterus to the left monitored by the placement of an electronic fetal monitor belt o one belt holds the ultrasound transducer to record the FHR

Assessment of fetal well-being Ch. 16 the other holds it tocodynamometer that detects uterine or fetal movement monitored for 20 minutes but may be extended to 40 minutes if fetus appears in sleep cycle o



Interpretation of NST 

 

2 or more fetal heart accelerations within a 20 minute o acceleration must be at least  15 beats per minute above the baseline  last 15 seconds from baseline to baseline a non-reactive abnormal NST = lacks FHR accelerations over a 40 minute spontaneous decelerations = variable o if not repetitive and brief- < 30 seconds do not indicate fetal compromise nor the need for intervention o repetitive variable decelerations- at least 3 in 20 minutes even if mild = increase risk for C-section



Variability (can only be determined with internal monitor) o Average variability: 5-15 beats around baseline o Minimal or decreased variability: 0-5 beats around baseline o Increased variability: > 15 beats around baseline

 

Acceleration – 15 bpm x 15 sec Decelerations o Early – Head compression  alteration of cerebral blood flow  shape is uniform with contraction  FHR returns to baseline before contraction is over  no treatment o Late – uteroplacental insufficiency (UPI)  Hypoxia depression of CNS  Shape mirrors and uniform to contraction  FHR returns to baseline after contraction ends  Repetitive= immediate delivery o Variable – Cord compression  Hypotension, decrease fetal cardiac output, hypoxia, metabolic acidosis  U, V, or W shape  Does not relate to contractions  FHR return is abrupt  Repetitive = immediate delivery

Assessment of fetal well-being Ch. 16





Managing decelerations (Late and Variable) o Reposition patient (preferably left lateral) o Administer oxygen via face mask (10 L / min) standing order o Give intravenous fluid bolus o Turn off Pitocin if running o Notify the physician VEAL CHOP o Variable decels = Cord compression o Early decels = Head compression o Accelerations = Ok o Late decels = Placental insufficiency

Clinical management    

If the NST is reactive after 20 minutes the test is concluded, and the woman is rescheduled for further testing testing may be performed weekly or twice weekly if warranted by maternal or fetal risk factors Reactive (good) = At least 2 accels in 20 min Non – reactive (bad) = < 2 accels in 20 min

Nursing management     

Important to ensure that the woman understands the indications for the NST, the equipment used, and procedure prior to beginning the tests position the woman apply the electronic fetal monitor monitor maternal blood pressure during the NST for hypotension Administered the NST and report the findings to provider and the patient

Assessment of fetal well-being Ch. 16 Contraction stress test      

evaluating the respiratory function of the placenta identify the fetus at risk for intrauterine asphyxia by observing the response of the FHR to the stress of uterine contractions During contractions intrauterine pressure increases blood flow to the intervals space is reduced in the placenta = decreasing oxygen transport to the fetus If the placental reserve is insufficient fetal hypoxia, depression of the myocardium, and a decrease in FHR occur contraindicated in cases of 3rd trimester bleeding o need for complete and comprehensive patient hx prior to starting the test is important

CST procedure

 

   



Presence of uterine contraction may occur spontaneously or they may be induced with oxytocin (Pitocin) IV oxytocin challenge test o Pitocin is given to see how baby responds to contractions natural method of obtaining oxytocin = breast stimulation electronic fetal monitor is used to provide continuous data about the fetal heart rate and uterine contractions after a 15-minute baseline recording of uterine activity and FHR = tracing evaluated for evidence of spontaneous contractions 3 spontaneous contractions of good quality and lasting 40-60 seconds in a 10-minute window = results are evaluated, and the test is concluded if no contractions occur or they are insufficient = oxytocin is administered IV or breast self-stimulation or application of electronic breast pump

CST result interpretation  



Negative CST (good)- 3 contractions of good quality lasting 40 or more seconds in 10 minutes without late deceleration Positive CST (bad)- repetitive persistent late decelerations with more than 50% of the contractions o not a desired result An equivocal or suspicious test- non persistent late decelerations or decelerations associated with tachysystole

Clinical application 

A negative CST = placenta is functioning normally, adequate fetal oxygenation, and the fetus will probably be able to withstand the stress of labor

Assessment of fetal well-being Ch. 16 

A positive CST with a non-reactive NST = fetus will not likely withstand the stress of Labor o identify compromised fetuses earlier than a non-reactive NST because of the interruption of intervillous blood flow

Amniotic fluid index   

Oligohydramnios = Decrease amniotic fluid volume diminish urinary output caused by fetal hypoxemia o placenta insufficiency may cause hypoxemia (Poly)hydramnios = increase AFV

Biophysical profile 

 







 

assessment of five fetal biophysical variables o FHR acceleration (assessed with NST) o fetal breathing (ultrasound scanning) o fetal movements (ultrasound scanning) o fetal tone (ultrasound scanning) o amniotic fluid volume (ultrasound scanning) BPP helps identify the compromise fetus and confirm the healthy fetus test is complete when all the variables have been adequately assess and should conclude in 30 minutes o > 30 minutes = abnormal assessment is most useful in women that have experienced decrease fetal movement and the management of IUGR, preterm labor, gestational diabetes, HTN disorders, post term pregnancies, and PROM the two most important components of the BPP = NST and amniotic fluid volume index o NST reflects the intactness of the nervous system o AFVI reflect kidney perfusion a normal AFVI = no shunting and kidneys are adequately functioning o normal variables = score of 2 (fetal breathing movement, body movements, fetal tone, NST, AFV) o abnormal variable = score of 0 o highest possible score is 10 Biophysical activities of the fetus that develop first are the last to disappear – due to asphyxia Biophysical activities that are last to develop and noted first – due to hypoxia

Modified biophysical profile 

Consists of an NST + a measurement of the amniotic fluid index

Assessment of fetal well-being Ch. 16

   

o reflect long-term uteroplacental function poorly functioning placenta = damage fetal renal perfusion leading to oligohydramnios the amniotic fluid by volume assessment can therefore be used to evaluate long-term uteroplacental function normal if AFP is > 5 centimeters and if the NST is reactive Abnormal if NST is not reactive or the AFI is 5 or >

Doppler Flow studies     









high risk pregnancy to determine placental functioning and the velocity of blood flow in the vessels an ultrasound to measure arterial or venous blood monitor vascular functioning series of waves the highest velocity peak = systolic measurement the lowest point = diastolic velocity

cerebroplacental ratio- used to detect abnormal blood flow and finishes with IUGR and late onset, small for gestation age fetus to detect fetal placental and uteroplacental dysfunction blood flow velocity- can be measured by the Systolic to diastolic ratio and reflects decreasing resistance of placental and umbilical vasculature for greater umbilical blood flow to meet the needs of a growing fetus resistance index- is another technique used to Detect blood flow resistance if the RI is greater than .58 it is considered abnormal and indicates alteration in perfusion at an increase risk of adverse perinatal outcomes post ductility index- has smallest measurement error but has a narrow window of normal values

Assessment of fetal well-being Ch. 16 Evaluation of placental maturity   

grading process that uses ultrasound to measure changes ...