Term
| Amnitic fluid is primarily produced from ____________ in the first trimester and the __________ in the second and third trimester. |
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Definition
| Chorioamnion perfusion, fetal kidneys |
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Term
| Name the functions of the amniotic fluid |
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Definition
- Prevents adherence of the amnion to the embryo
- Acts as a cushion to protect fetus
- Allows for free movement of the fetus
- Allows symmetric growth
- Maintains fetal temperature
- A source of fetal nutrition
- Essential for fetal lung development
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Term
In the first and second trimester amniotic fluid will vary depending on ___________ ________.
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Definition
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Term
| The normal range of amniotic fluid in the third trimester is ___________. |
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Definition
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Term
| A visual survey of the entire uterine cavity should be performed for a _____________ of amniotic fluid. |
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Definition
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Term
| What are the sonographic visual limitations in the presence of decreased fluid? |
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Definition
- Fetus is difficult to image
- Fetus appears crowded
- Unable to indentify any significant pocket of fluid
- Pocket of fluid less than 2 cm
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Term
| What are the sonographic findings of polyhydramnios? |
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Definition
- Fetus may have fluid completely surrounding trunk and limbs
- Fetal structures are easily identified
- Overall appearance of increased fluid
- Single pocket of fluid greater than 8 cm
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Term
| Describe the procedure in obtaining an amniotic fluid index. |
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Definition
- Maternal abdomen is divided by a midline vertical line - linea nigra and a horizontal line at the umbilicus
- Hold the transducer in the sagittal plane and perpendicular to table or floor.
- Measure the largest vertical pocket in each quadrant, excluding umbilical cord loops and fetal extremities.
- The four measurements are added together to get the sum index.
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Term
| What are some of the associated conditions of polyhydramnios? |
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Definition
- Fetal upper gastrointestinal obstructions
- fetal hydrops - Rh sensitization
- renal disorders (maternal)
- maternal diabetes
- skeletal anomalies
- central nervous system disorder
- cystic hygroma
- placental abnormalities
- maternal infections
- idiopathic (60%)
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Term
| What are some of the associated conditions of oligohydramnios? |
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Definition
- PROM
- IUGR
- post dates
- fetal demise
- renal abnormalities or agenesis
- fetal posterior urethral valve syndrome
- chromosomal abnormalities
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Term
| What fetal conditions can be caused by oligohydramnios? |
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Definition
- Can cause clubbing of hands and feet, dolichocephaly, pulmonary hypoplasia, hip displacement.
- Umbilical Doppler - restricted blood flow due to increase pressure on umbilical cord from lack of fluid.
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Term
| Increased maternal hydration can __________ amniotic fluid volume. |
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Definition
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Term
| What are the sonographic findings of amniotic band syndrome? |
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Definition
- Strand-like structures seen free floating in the amniotic fluid or extending through uterine cavity and attached to uterine wall.
- Various fetal malformations involving the limbs, craniofacial region, and fetal trunk, by entanglement and subsequent compression of the fetus.
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Term
| How do amniotic sheets and/or synechia appear on ultrasound? |
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Definition
- Echo dense line in uterine cavity separated from uterine wall by an echolucent space.
- Appear as a thick membrane, projecting into the amniotic fluid.
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Term
| An umbilical cord tha is considered a long cord measures _________ cm. |
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Definition
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Term
| The fetus is encapsulated by what structure in utero? |
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Definition
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Term
| Thrombosis of the umbilical vessels occurs most often in which vessel? |
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Definition
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Term
| Transabdominal sonography of the gravid uterus at 28 weeks as determined by LMP reveals a smoothly emarginated, anechoic mass arising grom the umbilical cord near the site of fetal insertion. Doppler evaluation fails to demonstrate blood flow within the mass. The most likely diagnosis is _________ or _________. |
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Definition
| Omphalomesenteric cyst or Allantoic cyst |
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Term
| An umbilical cord consists of |
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Definition
- Two small arteries - transport deoxygenated blood
- one large vein - transports oxygenated blood
- Wharton's jelly
- Amnion
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Term
| An important fact of umbilical cord abnormalities is the _________ umbilical artery is absent a higher percentage of time than the ___________. |
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Definition
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Term
| What are the associated abnormalities of a two vessel cord? |
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Definition
- Congenital anomalies (25-50%)
- cardiac defects
- Genitourinary anomalies
- skeletal abnormalities
- abdominal wall defects
- diaphragmatic hernia
- central nervous system disorders
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