US Protocol for Ectopic (last slide Class 11)
1.PURPOSE: identification of IUP (sac with decidual reaction
or fetal pole
2.VISUALIZATION OF IUP RULES OUT ECTOPIC FOR
ALL PRACTICAL PURPOSES
3.PERFORM SIMILAR SCAN TO COMPLETE PELVIC
EXAM
4.DRINKING OF WATER IS USUALLY
CONTRAINDICATED DUE TO SURGICAL POSSIBILITY
How long does the gestational period in the human usually last?
-9 calendar months
- 10 lunar months
- 40 weeks
- 280 days
What is the gestational period broken into?
TRIMESTERS
- this word came from a Latin word means "3 months long"
- 1st: weeks 1-12
- 2nd: weeks 13-26
- 3rd: weeks 27-40
,What are some of the changes that occur in the mother during
the gestational period?
- the FUNDUS rises superiorly as the fetus grows larger
- later in the pregnancy, UTERUS enlarges to such an extent that
it may exert PRESSURE on the urinary bladder and rectum =>
frequent urination and/or constipation
- urine volume increases b/c mother is processing fetal excretory
products as well as her own
- blood volume increases as the placenta develops
- respiratory activity increases in order to supply extra oxygen to
the fetus and get rid of carbon dioxide
- metabolism changes due to a hormone released by the placenta
Duration of first trimester
from 1st day of LMP until the 12th week
US during the first trimester
- during this trimester, fetus may be examined with US either
transabdominally or transvaginally
- entire uterus should be visualized, with special attention to
uterine cavity and conceptus
- if possible, both ovaries should be images
,structures visualized in first trimester
- gestational sac: seen by 5 weeks from LMP transvaginally
- yolk sac: seen 5.5 weeks from LMP transvaginally
- fetal pole with FHM (fetal heart motion): seen by 6 weeks
from lMP transvaginally
*when scanning transabdominally, these structures will be
imaged 1/2 week later than with transvag
When do the amnion and chorion fuse?
by 13-15 weeks of gestation
where is the fetal pole located?
within the amniotic sac
Where is the yolk sac located?
Between the amnion and chorion
placenta development
- By 7-8 weeks of gestation, the developing placenta can be seen
as a crescent shaped echogenic area on one side of the sac
(anteriorly)
- By 12 weeks the placenta can be clearly visualized
- By 20 weeks the borders of the placenta can be visualized
when does the fetus grow most rapidly?
during the first trimester
, how much does the fetal pole grow per day in first trimester?
2 mm/day
When does organogenesis occur?
during the first trimester, more specifically in first 10 weeks of
pregnancy
When is the fetus most susceptible to injury?
first trimester
by which week of gestation can the spine, head and developing
limbs be seen on US?
in the first trimester, by 9-10 weeks
When can the umbilical cord be visualized sonographically?
latter portion of first trimester
how is fetal heart motion (FHM) documented and measured?
using M-mode
when does the volume of amniotic fluid increase and when does
it decrease?
- increases until 36-38 weeks of gestation
- it then decreases until term
US appearance of amniotic fluid in the first and second trimester
anechoic
US appearance of amniotic fluid in the third trimester