1
Fetal Assessment
Lecture 3
I.
Fetal Assessment
A.
Indications for fetal diagnostic testing
1.
Biophysical-risk factors that originate within the mother
or fetus-affect the development or function of either
or both
a.
genetics
-defective genes
-inherited disorders
-chromosomal anomalies
-multiple pregnancies
-ABO incompatibility
b.
nutritional status
-teen moms
-3 pregnancies in last 2 years
-tobacco, alcohol, or drug use
-inadequate or excessive weight gain
-Hct less than 33%
c.
medical or obstetric
-chronic HTN
-PIH
-GDM or IDDM
-h/o PTL
-AMA
-h/o stillborn, fetal death
-sickle cell
-heart disease
-HIV
-bleeding problems
2.
Psychosocial-risks comprised of maternal behaviors
and adverse lifestyle that have a negative effect on
the health of the mother and/or fetus
a.
smoking
b.
caffeine
c.
alcohol
d.
drugs
e.
psychologic status
-h/o physical/verbal abuse
-inadequate support systems
-noncompliance with cultural norms
-situational crises
-unsafe cultural, ethical, or religious practices
2
B.
II.
3.
Sociodemographic-risks arise from the mother and her family
and place the mother and fetus at risk
a.
low income
b.
lack of PN care
c.
age
d.
parity
e.
marital status
f.
residence
g.
ethnicity
4.
Environmental-risks include hazards of the workplace
and the woman’s general environment
a.
infections
b.
radiation
c.
chemicals
d.
therapeutic drugs
e.
illegal drugs
f.
industrial pollutants
g.
smoke, stress, diet
Nursing Interventions
1.
Complete PN interview with history
2.
Offer access to services for health promotion
3.
Discuss reasons for health diet and lifestyle practices
4.
Emphasize need to keep PN visits and do lab work
5.
Educate patient/partner to play an active role in
health of the mother and fetus
Fetal diagnostic tests
A.
Biophysical Assessment
1.
Daily fetal movement count
a.
simple, noninvasive, done at home
b.
can be affected by fetal sleep cycle or maternal
drug use
c.
presence of fetal movement is generally a sign
of good health
d.
< 10 movements in 3 hours, CALL MD
e.
2 hours after a meal and still < 4, CALL MD
f.
follow up with NST, CST, or biophysical profile
3
2.
Ultrasound
a.
indicators
-gestational age
-multiple gestations
-fetal growth patterns
-fetal congenital anomalies
-placental position and maturity
-affects of disease process on the fetus
-assess fetal responses to intrauterine environ.
-assist with amniocentesis, CVS, fetoscopy, etc.
b.
data
-reflections of echoes that are produced when
sound waves are dispersed to and
absorbed by tissues being scanned
-no recognizable risks to mother or baby
-full bladder helps to lifts up the uterus
-transvaginal probe
1.
allows for better visualization of pelvis
2.
good to use on obese patients
3.
allows pregnancy to be determined
earlier
4.
well tolerated, no full bladder
5.
helps detect ectopic pregnancies
6.
used in adjunction with abdominal
scan to R/O PTL in 2nd & 3rd trimesters
-abdominal scan
1.
full bladder helps move uterus up
2.
may be hard to use on obese pts.
3.
more useful after 1st trimester
-fetal heart activity by 6-7 week by echo scanner
-gestational age
1.
gestational sac dimensions-8 weeks
2.
crown-rump length-7-14 weeks
3.
biparietal diameter (BPD)-12+ weeks
4.
femur length-12+ weeks
-amniotic fluid volume (AFV or AFI)
1.
ck fluid-filled pockets without fetal
parts or cord
2.
AFI-depth of fluid in all 4 quads
-< 5cm=oligo
-5-19 cm=normal
-over 20 cm=poly
3.
decreased AFV-largest pocket of fluid is
<2 cm
4.
increased AFV-multiple large pockets of
fluid > 12 cm
4
3.
B.
MRI-magnetic resonance imaging
a.
noninvasive, no known effect on fetus
b.
evaluate fetal growth
c.
evaluate fetal structure
d.
evaluate placental growth, position
e.
AFV
f.
maternal structures
g.
biochemical status
h.
soft tissue, metabolic, or functional malformations
Biochemical Assessment
1.
Amniocentesis
a.
transabdominal insertion of a needle into uterus
b.
done after week 14 when uterus is in the abd.
c.
indications for:
-PN diagnosis of genetic disorders
collection of fetal cells in fluid
karyotype done
↑ AFP level-possible neural tube defect
-congenital anomalies
-assessment of lung maturity
L/S ratio of 2:1 or +PG or LBC >50,000 cts/UL
-dx fetal hemolytic disease
d.
complications
-less than 1% of cases
-PTL/miscarriage
-infection
-hemorrhage(Rh – moms get Rhogam)
-amniotic fluid embolism
-injury to fetus/fetal death
2.
PUBS-percutaneous umbilical blood sampling
a.
also known as cordocentesis
b.
used during 2nd or 3rd trimester
c.
used for blood sampling or transfusion
d.
insert needle into fetal vessel using U/S
e.
used to dx fetal blood disorders, karyotype,
blood type, and coombs
f.
assess FHR for 1 hour and rescan in 1 hour
3.
CVS-chorionic villus sampling
a.
done at 10-12 weeks
b.
remove small tissue from fetal portion of placenta
c.
indicative of fetal genetic makeup
d.
use transcervical or transabdominal approach
e.
complications
-abortion
-infection
-bleeding
5
f.
g.
h.
4.
C.
Rhogam given to Rh – moms
90% of procedures done on women > 35 yrs old
because done early, can’t detect neural tube
defects
maternal blood sampling
a.
California Prenatal Screening Program
-see booklet for blood test and U/S offered
b.
Coombs
-test for Rh incompatibility
-indirect=amt. of Rh+ antibodies in mom’s blood
-direct=presence of antibody-coated Rh+ RBCs
in baby’s blood
-determine severity of fetal anemia from
hemolysis
Electronic FHR assessment
1.
FHR tracing-assessment and interpretation
a.
baseline
-range of FHR in a 10 minute period in the
absence of or between U/C’s
-110-160 bpm
b.
variability
-98% accuracy in predicting fetal well-being
-result of fetal sympathetic/parasympathetic
nervous systems
-can be affected by fetal sleep cycle, maternal
analgesics, prematurity, congenital
anomalies
-decrease in variability-possible sign of fetal
distress or profound compromise
c.
bradycardia
-FHR below 110 bpm for 10 minutes or more
-indicative of fetal hypoxia
d.
tachycardia
-FHR over 160 bpm for 10 minutes or more
-marked tachycardia > 180 bpm
-prematurity
-mild hypoxia
-tocolytic agents
-maternal fever
-maternal anemia
-fetal activity
e.
changes in FHR
-accelerations-usually assoc. with + FM
-decelerations-early, late, variable
2.
nursing role
a.
record information on strip if unable to chart
b.
vaginal exams
c.
assess if ROM
6
d.
e.
f.
g.
h.
i.
3.
D.
VS assessments
position changes when needed
oxygen via mask
medications
emesis control
assess need for internal monitors
deceleration patterns
a.
early-rarely below 110 bpm
-periodic decels R/T intense fetal head
compression
-uniform shape, mirror image of U/C
b.
late
-uniform-reflects shape of contraction
-onset after peak of U/C
-repetitious
-cause-uteroplacental insufficiency
-hypotension
-PIH
-hypertonic contractions
-abruptio
-postmaturity
-IUGR
-DM
-action
-oxygen
-position change
-stop pitocin drip
-IV hydration
-assess other S & S
c.
variable
-U or V shaped
-with or without U/C
-R/T cord compression
-usually transient, changeable
-action
change to side lying
oxygen
external fetal manipulationSVE
knee-chest position
amnioinfusion if ROM
Electronic fetal monitoring
1.
Nonstress test-(NST)
a.
healthy fetus with intact CNS, 90% will have FHR
accelerations with gross body movements
b.
blunted by hypoxia, acidosis, drugs, fetal sleep
c.
reactive if:
-normal baseline rate
-2 or more accelerations (15X15) in 20 min.
-moderated variability
d.
nonreactive or unsatisfactory
-need further monitoring, consider CST/BPP
7
E.
2.
Contraction stress test-(CST)
a.
provides a warning of fetal compromise earlier
than NST
b.
U/C’s decrease uterine blood flow/placental
perfusion-hypoxia to fetus=deceleration in FHR
c.
FHR is monitored for at least 15 minutes
d.
nipple-stimulated CST
-massage nipple until contraction is elicited
-desire 3 U/C’s/10 minutes/lasting 40-60 sec
e.
oxytocin-stimulated CST
-IV infusion of oxytocin to start U/C’s
-increased in 0.5 mU/min increments
f.
negative results
-no late decels
g.
positive results
-persistent and consistent late decels with more than
half the contractions
3.
Fetal oxygen saturation
a.
FSpO2 may be helpful in differentiating fetal
hypoxia
b.
adjunct to EFM
c.
normal FSpO2 may prevent unnecessary
interventions when a nonreassuring FHR pattern
is identified
d.
ROM is needed
e.
signal error if improperly placed, too hairy, or
too much vernix
f.
normal FSpO2 during labor is between 30-70%
Biophysical profile
1.
noninvasive dynamic assessment of fetus/environment
2.
assessing 5 variables
a.
fetal breathing movements
-normal (2)-one or more episodes in 30 min
lasting > 30 seconds
-abnormal (0)-absent or no episode matching
requirement above
b.
gross body movements
-normal (2)-3 or more movements/30 min
-abnormal (0)-none or less than 3/30 min
c.
fetal tone
-normal (2)-1 or more active extension with
return to flexion
-abnormal (0)-slow extension with return
d.
reactive fetal heart rate
8
e.
3.
F.
-normal (2)-2 or more accels with +FM/20 min
-abnormal (0)-less than requirement
qualitative amniotic fluid volume
-normal (2)-1 or more pockets of fluid > 1 cm in
2 perpendicular planes
-abnormal (0)-pockets absent or below needed
score
a.
normal = 8-10 if AFI ok
b.
equivocal = 6
c.
abnormal = <4
Role of the Nurse in Fetal Assessment Testing
1.
support person when the woman is undergoing exams
such as U/S, amnio, PUBS, CVS, etc
2.
in some settings, the RN will perform the NST, CST,
BPP, and basic U/S
3.
patient teaching
a.
preparation for procedure
b.
interpreting the findings
d.
providing psychosocial support PRN
01/16