Module 4 - Fetal Assessment (Exam 2) 1 Flashcards
Indications for Fetal Asessment Testing
- To detect congenital anomalies
- To evaluate the condition of the fetus
Ultrasound
Frequently used diagnostic tool throughout pregnancy. Intermittent ultrasonic waves are transmitted by a transducer. Ultrasonic waves deflect off tissues, showing images of different densities.
Advantages of Ultrasound
- Non-invasive
- Painless
- No known side effects for fetus or patient
- Information obtained is abundant and accurate
Transabdominal Ultrasound
Placedon patient’s abdomen
Transvaginal Ultrasound
Inserted into vagina
Nursing Responsibilites regarding Ultrasound
- Educate:
- Full bladder for transabdominal ultrasound in early pregnancy
- Empty bladder for transabdominal ultrasound in late pregnancy
- Remain in one position for 20-30 minutes
- Abdominal or vaginal pressure
- Support the patient
What should you tell the patient regarding urination during an early pregnancy ultrasound?
Full bladder
What should you tell the patient regarding a late pregnancy ultrasound?
Empty the bladder
Indications for Ultrasound in Early Pregnancy
- Confirm Pregnancy
- Viability of fetus
- Location of pregnancy
- Determine gestational age
- Screening for potential fetal anomalies
- Identify multiple gestations
- Visualization for other procedures
Indications for Ultrasound in Mid Pregnancy (20 weeks)
- Evaluate fetal anatomy, organ structure, and function
- Identify gender
- Head and chest circumference and femur length (assess fetal growth)
- Less accurate in dating of pregnancy
Indications for Ultrasound in Late Pregnancy
- Check on fetal well-being (fetal oxygen status)
- Biophysical profile
- Amniotic fluid index
- Locate Placenta
- Estimate fetus size
- Visualization for other procedures
- Fetal presentation
- Portable ultrasound at bedside (triage/labor)
Multiple Marker Screening
Screens for chromosomal abnormalities and neural tube defects. It is an adequate first screening to determine need for more invasive testing. Evaluates substances found in maternal serum from fetal liver.
- Trisomy 21 and 18
- Spina bifida, meningocele, anencephaly
Which substances does the Multiple Marker Screening evaluate from the maternal serum?
Substances found in maternal serum from fetal liver:
- Alpha-fetoprotein (AFP)
- Human chorionic gondotropin (HCG)
- Unconjugated estriol
When is the Multiple Marker Screening performed?
- Completed between 15-20 weeks gestation
Multiple Marker Screening Results
- Maternal levels are compared to normal levels for the number of weeks gestation
- Abnormal Levels
- 60% accurate for chomosomal anomalies (trisomy 18 and 21)
- 80-90% accurate for neural tube defects
- False positive rate is most frequently due to inaccurate estimation of gestational age
Amniocentesis
To obtain amniotic fluid by use of a needle for a variety of tests
When is amniocentesis performed?
- Second trimester (15-20 weeks)
- After 35 weeks
Amniocentesis Second Trimester
- Screen for or confirm presence of choromosomal abnormalities
- Confirm a neural tube defect (follow up for a positive multiple marker screen)