Diagnostic Testing OB

Order of phases of ACUTE fetal hypoxia

1. Have nonreactive NST 2. Stop "practicing breathing because it doesn't have to. 3. Will stop moving 4. Muscle tone will be lost

The two components of BPP are

1. NST 2. Ultrasound for visualizing AFI, Fetal breathing, fetal movement, and fetal tone.

A positive screen for gestational diabetes

A glucose value of 140 mg/dl is considered a positive screen and should be followed by a 3-hour oral glucose tolerance test.

Increased Amniotic Fluid Volume indicates

Compensation is occurring, sign of CHRONIC fetal hypoxia

Reasons why a NST is Unreactive

DM PIH IUGR Maternal trauma Decreased FM Chronic maternal disease Oligohydramnios (low fluid) Rh isoimmune disease

PUBS is done for what?

Done to dx inherited blood disorders, karyotyping of malformed fetuses, detection of fetal infection, determination of acid-base balance of IUGR fetus, To assess and treat isoimmunization and thrombocytopenia. Can precisely identify fetal blood type and RBC count and Allows for transfusion earlier than through intraperitoneal route

Biophysical profile (BPP)

Fetal breathing movements Gross body movements Fetal Tone Reactive fetal heart rate Qualitative amniotic fluid volume Normal 8-10 Equivocal- 6 Abnormal <4

Complications associated with PUBS

Hemorrhage Cord laceration Preterm labor PROM Infection

After + GD screen a 3 hr OGTT

Is administered after an overnight fast and at least 3 days of unrestricted diet and physical activity. Mom needs to avoid caffeine because it tends to increase glucose levels, and to abstain from smoking for 12 hours before and during the test. A fasting blood glucose level is drawn before giving a 100 g glucose load. Blood glucose levels are then drawn 1, 2, and 3 hours later

Coombs Test

Jaundice testing for baby. Blood test. Test is looking for "foreign" antibodies that are already adhered to the infant's rbcs, a potential cause of hemolysis. Most commonly recognized forms of antibody-mediated hemolysis in newborns are Rh incompatibility and ABO incompatibility.

Percutaneous Umbilical Blood Sampling (PUBS)

Needle inserted directly into fetal cord vessel

Fetal Body Movement during 30 Minute Observation Period

Normal: 3 discrete and definite movements of the arms, legs or body Abnormal: Less than 3 discrete movements of arms/legs or body

Fetal Muscle Tone during 30 Minute Observation Period

Normal: Arms and legs are usually flexed with head on chest. One definite extension and return to flexion Abnormal: Arms and legs are usually flexed with head on chest - No flexion

Amniotic Fluid Volume

Normal: Largest Pocket of fluid is greater than 1 cm in vertical diameter without containing loops of cord Abnormal: Largest pocket is less than 1 cm in vertical diameter without loops of cord

Fetal Breathing Movement during 30 Minute Observation Period

Normal: One breathing period lasting at least 60 seconds Abnormal: Breathing period less than 60 seconds or no breathing observed

When to screen for gestational diabetes?

Screening should be performed at 24-28 weeks of gestation.

TORCH stands for

Toxoplasmosis Other (HepA/HepB) Rubella Cytomegalovirus Herpes

Vibro Acoustic Stimulation (VAS)

Use of 3-5 second auditory and vibratory stimulus

BPP

Uses real time u/s -noninvasive assessment Uses u/s and nonstress test Assesses Central hypoxia results in alterations in movement, muscle tone, breathing, heart rate. accurate indicator of impending fetal death, when abnormal score encountered with oligohydramnios labor induction is indicated. Can also assess for fetal infection with SROM or prom Graded on score of 2 or 0- 5 items each gets 2 points.

Fern test

a microscopic slide test to determine the presence of amniotic fluid leakage. By use of sterile technique, a specimen is obtained from the external os of the cervix and vaginal pool. Fluid is examined on a slide under a microscope. A fernlike pattern occurring from the salts of amniotic fluid indicates the presence of amniotic fluid

Goal of VAS

acceleration of 15 beats for 15 seconds following stimulation

Unsatisfactory contraction stress test

adequate uterine contractions cannot be achieved, or the FHR tracing is not of sufficient quality for adequate interpretation.

Chorionic villus sampling (CVS)

aspiration of a small sample of chorionic villus tissue at 8 to 12 weeks' gestation. Test is performed for the purpose of detecting genetic abnormalities; obtain informed consent.

Amniocentesis

aspiration of amniotic fluid done from 14 weeks of pregnancy or thereafter. Performed to determine genetic disorders, sex of the fetus, and fetal lung maturity. Risks: maternal hemorrhage, infection, Rh isoimmunization, abruptio placentae, amniotic fluid emboli.

NST will

assess for acute fetal acid base status

Contraction stress test

assesses placental oxygenation and function. Determines fetal ability to tolerate labor and determines fetal well-being. Fetus is exposed to the stressor of contractions to assess the adequacy of placental perfusion under simulated labor conditions. PERFORMED IF NST IS ABNORMAL.

Alpha-fetoprotein screening (AFP)

assesses the quantity of fetal serum proteins; if elevated, is associated with open neural tube and abdominal wall defects. Can detect spina bifida and Down syndrome.

Unsatisfactory NST

cannot be interpreted because of the poor quality of the FHR tracing.

Equivocal contraction stress test

contains decelerations but with less than 50% of the contractions, or the uterine activity shows a hyperstimulated uterus.

Alpha-fetoprotein screening (AFP) Implementation

explain that the level is determined by a single maternal blood sample drawn at 15 to 18 weeks of gestation. If the level is elevated and the gestation is less than 18 weeks, a second sample is drawn. An ultrasound is performed for elevated levels to rule out fetal abnormalities or multiple gestation.

Nonstress test (NST) Implementation

external ultrasound transducer and the tocodynamometer (toco) are applied to the mother, and a tracing of at least 20 minutes' duration is obtained so that the FHR and the uterine activity can be observed. Obtain baseline blood pressure (BP) and monitor BP frequently. Place the mother in the left lateral position to avoid vena cava compression. The mother may be asked to press a button every time she feels a fetal movement, the monitor records a mark at each point of fetal movement, which is used as a reference point to assess FHR response.

Ultrasound Implementation

if the abdominal ultrasound is being performed, the woman usually needs to have a full bladder to obtain a better image of the fetus. Not harmful to fetus

Reactive Nonstress Test (Normal/Negative)

indicates a healthy fetus. Two or more FHR accelerations of at least 15 beats per minute, lasting at least 15 seconds from the beginning of the acceleration to the end, in association with fetal movement, during a 20-minute period.

CVS Implementation

instruct the client to drink water to fill the bladder before the procedure, to aid in positioning the uterus for catheter insertion. Lithotomy position. Instruct the client to report bleeding, infection, or leakage of fluid at the insertion site after the procedure. Rh-negative women may be given RhoGAM for risks related to the procedure.

Kick counts (fetal movement counting)

mother sits quietly or lies down on the left side for 1 hour after meals and counts fetal kicks for 30 minutes. Instruct the client to notify the physician or health care provider if there are fewer than 3 kicks in 1 hour.

Nonreactive Nonstress Test (Abnormal)

no accelerations or accelerations less than 15 beats per minute or lasting less than 15 seconds in duration for a 40-minute observation.

Amniocentesis Implementation

obtain informed consent, instruct the client to empty the bladder before the procedure, prepare the client for the ultrasound, which is performed to locate the placenta, obtain baseline vital signs and fetal heart rate (FHR), and monitor every 15 minutes, place the client in the supine position, instruct the client to notify the physician or health care provider if chills, fever, leakage of fluid at the needle insertion site, decreased fetal movement, or uterine contractions occur.

Ultrasound

outlines and identifies fetal and maternal structures. Assists to confirm gestational age and estimated date of delivery. May be done abdominally or transvaginally during pregnancy.

Quad Screen must be

performed between the 16th and 18th week of pregnancy.

Nonstress test (NST)

performed to assess placental function and oxygenation. Determines fetal well-being. Evaluates fetal heart rate (FHR) in response to fetal movement.

Fern test Implementation

place the client in the dorsal lithotomy position. Instruct the client to cough to cause the fluid to leak from the uterus if the membranes are ruptured.

Nitrazine test Implementation

place the client in the dorsal lithotomy position. Touch the test tape to the fluid. Assess the test tape for a blue-green, blue-gray, or deep blue color, which indicates that the membranes are probably ruptured.

Positive contraction stress test abnormal

represented by late or variable decelerations of the FHR with 50% or more of the contractions in the absence of hyperstimulation of the uterus

Negative contraction stress test

represented by no late or variable decelerations of the FHR

If we are even doing a BPP then we know

that the NST came out nonreactive

Contraction stress test Implementation

the external fetal monitor is applied to the mother, and a 20- to 30-minute baseline strip is recorded. The uterus is stimulated to contract either by the administration of a dilute dose of oxytocin (Pitocin) or by having the mother use nipple stimulation until three palpable contractions with a duration of 40 seconds or more in a 10-minute period have been achieved. Frequent maternal BP readings are done, and the mother is monitored closely while increasing doses of oxytocin are given.

Screening for gestational diabetes

the screening test consists of a 50 g oral glucose load, followed 1 hour later by a plasma glucose determination. It is not necessary that the woman be fasting.

The woman is diagnosed with gestational diabetes if

two or more values are met or exceeded.

Nitrazine test

use of a nitrazine test strip to detect the presence of amniotic fluid in vaginal secretions. Vaginal secretions have a pH of 4.5 to 5.5 and do not affect the yellow Nitrazine strip. Amniotic fluid has a pH of 7.0 to 7.5 and turns the yellow Nitrazine strip or swab blue.