Blind to Visualized
 The
endometrium
has two layers: functionalis and basalis. The functionalis (functional)
layer is superficial and is shed each month during menstration. The
basalis (basal) layer is a permanent layer that gives rise to
regeneration of endometrium after each menstration.
The myometrium
is the muscle layer under the endometrium. It is the bulk of the
uterine wall. The basal layer of the endometrium is embedded in the
myometrium.
The perimetrium
is the thin outermost layer of the uterus. It
is also
referred to as the outer uterine wall.
Since
doctors do not see the inside of the woman’s uterus
when
performing this D&C
surgery it is often
labeled a “blind surgery”. The scraping and/or
suctioning inside the uterus is
performed by viewing only what is external to it: the
doctor’s own hands, the
patient’s vagina and cervix and a portion of the instruments.
This can lead to
removing too little (leaving behind RPOC which may lead to needing
another
procedure) and can also lead to going too deeply, (such as damaging the
basal
layer of endometrium or removing superficial myometrium--uterine
muscle). See
above image.
A
woman should ask if the procedure is being done with
hysteroscopic guidance or ultrasound guidance. If it is not, the
physician
should give a clear explanation. If she is satisfied with the answer,
they
could proceed, if she is not, she could seek another doctor’s
opinion.
| An ultrasound can
be used to move a
blind D&C toward being a visualized surgery. |
On
the one hand, the ability to visualize tissue via
transabdominal ultrasound varies depending on the reason for the
D&C. If
the D&C is for a miscarriage, early pregnancy termination or
small retained
placental fragments, the tissue may not be visualized by transabdominal
ultrasound during surgery, on the other hand this tissue can usually be
seen
via vaginal ultrasound; however this would not help in the case of
intraoperative ultrasound, only pre and postoperative purposes.
According
to Criniti and Lin (2005), intraoperative
ultrasound has been shown to decrease both operative time and
complication
rates in D&Cs. They reported that ultrasound guidance could
assist the
surgeon by “seeing” a woman’s anatomy
during surgery. Ultrasound guidance would
result in reducing complication and re-operation rates and would also
make the
procedure less traumatic because the scraping and/or suctioning can be
focused and
limited rather than random and generalized (9).
Example:
Being able to see can be of great assistance to the
doctor. For instance, if a woman has two pieces of retained placental
pieces on
the right side of her uterus, the doctor does not need to suction
and/or scrape
the entire uterus to remove these pieces because he/she can see their
location
using ultrasound. On the other hand, it also increases the chance that
both pieces
will be identified and removed, so that a second D&C will not
be required.
| A
hysteroscope enters the uterus directly,
thus allowing for complete direct visual inspection of the cavity and
removal of RPOCs (retained products of conception). |
Hysteroscopy
is the only way to visualize the inside of the
uterus directly and thus is more accurate in identifying internal
structures
such as RPOCs, polyps, IUA, etc. than is ultrasound (10).
A
hysteroscope is placed into the uterus
through the cervix. A liquid (such as saline) or gas (such as carbon
dioxide),
is used to distend the uterine cavity, so that its interior and
contents can be
viewed clearly. It is also possible to perform surgery, an operative
hysteroscopy,
using this telescope and miniature surgical instruments (other than a
curette
or suction device). Although not many physicians are comfortable with
and expert
at hysteroscopic surgery--especially in the face of uterine bleeding
and/or retained
products of conception--the trend towards less blind and more
“targeted”
surgery is underway.
WHAT
CAN PATIENTS DO? If
expectant and/or medical management options
have been explored, you can request that ultrasound be used (before,
during,
after) to guide your D&C or that an operative hysteroscopy be
performed to
guide removal of the RPOCs.
| A
D&C for post
partum hemorrhage can be a lifesaving
procedure. |
If
a
patient has very heavy vaginal hemorrhage to the degree
where her vital signs (blood pressure, pulse, etc.) are not stable, a
D&C
should be performed immediately. Medical therapy is not appropriate in
this
circumstance. A D&C should be considered after failure of
medical therapies
such as methergine and prostaglandins and a D&C is less
invasive with fewer risks than uterine
artery embolization or a hysterectomy. Immediately following a
delivery, since a woman’s
cervix is dilated, it is rarely possible to perform a hysteroscopy
since the
distending medium would escape.
|