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Practical Training and Research in Gynecologic Endoscopy
Training
in diagnostic laparoscopy
G. de Candolle
Geneva WHO Collaborating Centre for Research in Human Reproduction
A.G. Gordon
BUPA Hospital, Hull and East Riding
Introduction
Diagnostic laparoscopy is indicated in any situation when inspection
of the abdomen will help establish a diagnosis and to define subsequent
treatment. Patients that are to undergo endoscopic surgery should have a
complete pre-operative evaluation prior to scheduling the surgery. The preoperative
evaluation often includes laboratory and echographic exams in order to determine
the clear indication for surgery. The following text describes the usual
operating room set up and procedures for a diagnostic laparoscopy.
Positioning of the patient / Anesthesia
The patient is transported to the operating room and general anesthesia
performed. Following this, place the patient in modified dorsolithotomy
position. This position is most practical for operating and allows easy
mobilization of the uterus as well as access for hysteroscopy. Some operating
tables may be repositioned intraoperatively, allowing the surgeon to change
the angle of the legs. Special care should be taken to avoid nerve injury
by mal positioning the patient, particularly along the popliteal fossa and
brachial plexus. If any part of the patient is in contact with a metal object,
she may be at risk of electrosurgical burns.
General anesthesia is preferred for laparoscopy as it provides adequate
muscle relaxation and assisted respiration particularly as the patient is
in Trendelenburg position.
Disinfect the vagina, paying special attention to the umbilicus. Empty
the urinary bladder. Some surgeons prefer to leave a Foley catheter in place
throughout the procedure. We maintain continuous Foley drainage in selected
operations, such as a Burch procedure or hysterectomy. These procedures
often require longer operating times and are more likely to result in injury
to the bladder. For simpler procedures, we simply empty the bladder at the
beginning of the operation. Place a tenaculum on the cervix and insert the
uterine cannula. This cannula will allow the uterus to be manipulated and
should have the capability to perform chromopertubation.
Position of the operating team and equipment
The surgeon must be familiar with the mechanics and operation of each
piece of equipment. Prior to anesthetizing the patient the operating team
must check that the insufflator is functioning and has an adequate supply
of gas, the light source is functioning, and the video equipment is in working
order. This will prevent avoidable malfunctions which may result in serious
complications and surgical delays. Mobile racks for camera and TV monitor,
video-recorder, light-source and insufflator are available and help organize
the operating room equipment.
The surgeon stands on the left side of the patient, the nurse next to
him and the assistant on the opposite side. From here, the surgeon is able
to continuously monitor all of the equipment (insufflator, light-source,
irrigation system, electric generator). Alternatively, the surgeon and his
assistant may both stand to the left of the patient with the video monitor
on the opposite side. The TV monitor (1 or 2) should be located so that
each member of the operating team may follow the procedure. If there is
only one monitor, it is best placed at the feet of the patient.
Instruments
To perform a basic diagnostic laparoscopy one must have equipment to
create a pneumoperitoneum, light source, video, a cable and telescope, and
instruments to manipulate the uterus and adnexea.
Distention media
The peritoneal cavity is a potential space which only allows visualization
of the pelvic organs with adequate distention. The gases commonly used for
laparoscopy are carbon dioxide (CO2) and nitrous oxide (NO2).
Carbon dioxide is more readily absorbed, non-toxic, and does not support
combustion. The only serious risk is that of hypercarbia which only develops
at an absorption rate of greater than 100ml/min. For this reason, patients
are generally hyperventilated during surgery. The intra-abdominal pressure
should not rise above 15mm Hg, higher pressures will increase the absorption
rate and risk of gas embolism. Carbon dioxide embolism has been reported
at a rate of 1:10,000 to 1:60,000. Early diagnosis may be made by auscultating
the characteristic "mill wheel" murmur.
Nitrogen is less readily absorbed by body fluids and may lead to subphrenic
discomfort. It is also not flammable and does not support combustion. The
risk of embolism is similar to that for carbon dioxide.
The surgeon must also choose between a large array of gas insufflating
systems, both mechanical and electronic. The electronic system maintains
the intra-peritoneal pressure at a constant pre set level. Thus the surgeon
may perform the procedure without having to constantly monitor the pressures
and volumes.
Basic instruments
- Veress' needle.
- One 10-12 mm trocar to pass the laparoscope.
- Two to three 5 mm trocars (through which to pass instruments).
- One 10-12 mm trocar for larger instruments.
- Uterine manipulator.
- Laparoscopic scissors.
- Atraumatic grasping forceps.
- Smooth forceps designed for grasping the tubes.
- Bipolar electrocoagulator.
- Mobilizer (if possible with graduations).
- High flow irrigation-aspiration system.
- CO2 laser coupler (optional) and adequate back-stop device.
Instruments for more advanced procedures
- Unipolar electrocoagulator.
- Two needle holders.
- Clip forceps.
Minimal equipment required to perform laparoscopy
- High luminosity laparoscope with 10 mm trocar.
- 400 W light source.
- CO2 insufflator automatically regulated for pressure and flow rate.
It should enable a high rate of CO2 (at least 6 l/min.).
- Video camera and screen.
- Irrigation-aspiration system with high flow.
- Equipment for bipolar and unipolar electrosurgery.
- Endoscopic instruments: scissors, 2 forceps (one atraumatic), bipolar
coagulating forceps, clip forceps.
- Three secondary trocars 5 mm.
- One secondary trocar 10-12 mm.
Operating Procedure
Pneumoperitoneum
Insert the Veress'' needle through a vertical, 1 cm intraumbilical incision.
In general a 7cm length is sufficient although a 15cm needle is also available
for very obese patients. Prior to insertion the spring mechanism is checked
on the needle to help avoid visceral puncture. At this intraumbilical site
the abdominal wall is thinnest with no intervening fat and the peritoneum
closely underlying the fascia.
To insert the Veress' needle the abdominal wall is lifted with one hand
and the needle passed through the incision. Intraperitoneal placement is
confirmed by injecting 5 ml of saline through the Veress' needle. The solution
should flow without resistance and should not return when trying to aspirate.
Next, deposit a drop of saline on the external os of the needle. It should
fall into the needle hub when negative pressure is created by lifting the
anterior abdominal wall. Next, insuffltate carbon dioxide at a low flow
rate of 2 liters/minute, allowing the patient to adapt gradually to the
pneumoperitoneum. When a pressure of 14 mm of mercury is obtained, place
the machine should on automatic flow in order to maintain this pressure.
Most machines will automatically adjust the flow rate (usually at a maximum
flow of 6 l/min.).
In rare cases adhesions or extreme obesity may limit the surgeons ability
to use the Veress' needle intraumbilically. If these situations arise, the
surgeon may either perform and open laparoscopy or insert the Veress' needle
through the posterior vaginal fornix.
Placement of trocars
After attaining a sufficient pneumoperitoneum, place one 10-12 mm umbilical
trocar through the Veress' needle incision. The distal tip of the trocar
must be sharp. During insertion of the trocar, compress the upper abdominal
wall with the free hand to make the lower abdominal wall tense, giving a
firm platform against which to insert the trocar and cannula. Direct the
trocar towards the pelvis to avoid injury to major vessels.The trocar should
pierce the peritoneal cavity as high as possible to assure a panoramic view.
Occasionally, the trocar must be placed above the umbilicus (this must be
done under direct laparoscopic visualization through an initial umbilical
site).
Pass the laparoscope through the trocar sleeve and immediately confirm
correct intraperitoneal placement. Standard diagnostic laparoscopes vary
in diameter from 5-11mm. The 5mm laparoscope is adequate for inspection
but is not sufficient for more complex procedures. The light source is also
an essential element. In general the standard 150 watt light source is sufficient
only for diagnostic laparoscopy. Complex procedures requires a more powerful
light (250-400 watt halogen lamp).
Next, place the patient in Trendelenburg position in order to allow for
the gravitational effect to move the bowel out of the pelvic cavity. Then
insert two or three 5 mm trocars under direct vision at ancillary puncture
sites for instruments. These secondary trocars are inserted suprapubically,
taking care to avoid the epigastric vessels laterally and the bladder medially.
While inserting these ancillary trocars, angle toward the pouch of Douglas
while the uterus is held in ante-version. Secondary 8-12 mm, rather than
5 mm trocars, may be useful for some procedures.
Collaboration with the anesthetist
The pressure of the pneumoperitoneum and the extent of the Trendelenburg
position must be adapted to the hemodynamic and respiratory demands of each
individual patient. Continued communication and collaboration with the anesthetist
throughout the procedure is mandatory. This is extremely important because
it may be necessary to reduce the Trendelenburg position, lower the intraabdominal
pressure, or even convert to laparotomy at any time during the procedure.
Inspection of the abdomen and pelvis
It is important to approach the evaluation of the pelvis in a systematic
and thorough manner.
Upper abdomen
Begin the inspection with the upper abdomen. Rotate the laparoscope to
view the caecum and appendix, using a probe if necessary. Examine the course
of the ascending colon to the hepatic flexure. Examine the right lobe of
the liver and gall bladder. Sub-diaphragmatic adhesions may indicate prior
pelvic inflammatory disease (Fitz-Hugh-Curtis Syndrome). Avoiding the ligamentum
falciparum, the laparoscope is rotated to view the left lobe of the liver
and stomach. And finally, rotate the laparoscope around to view the descending
colon.
Uterus, fallopian tubes
Next, examine the pelvic organs starting with the uterus. Note its shape,
size, position, and mobility. Noting these characteristics may guide in
making the diagnosis of either uterine myomas, adenomyosis, or aberrant
Mullerian duct fusion. Look at the anterior cul-de-sac and round ligaments
for evidence of endometriosis. Inspect the fallopian tubes entirely with
the aid of a probe or forceps. Follow the length of the tube looking for
evidence of prior infection or endometriosis. Note the thickness of the
wall and mobility of the ampulla. Note all peritubal adhesions, or hydrosalpinxes.
In cases of infertility, after completing the inspection of the pelvic organs,
proceed with chromopertubation to evaluate tubal patency (see below). A
more sophisticated technique for evaluating the fallopian tube is salpingoscopy,
for a more detailed examination of the tubal mucosa.
Ovaries
Complete the inspection of one round ligament, fallopian
tube and ovary before continuing on with the opposite side. The ovary is
manipulated with a probe or forceps in order to examine its entire surface
and evaluate its mobility. Again note any signs of endometriosis or adhesion
formation.
Uterosacral ligaments
Finally, examine both uterosacral ligaments and the
pouch of Douglas. For a clear view it may be necessary to aspirate the free
fluid. Again, this is a common site for endometriosis and adhesion formation.
Chromopertubation
Chromopertubation is a basic element of a diagnostic
laparoscopy for infertility to assess tubal patency. Inject a dilute solution
of methylene blue (1:20 solution) through the cervical cannula. Follow the
passage of the liquid through the fallopian tube a verify passage of dye
through the fimbria.
Closure of abdominal incisions
After completing the evaluation of the pelvis or endoscopic procedure,
in more advanced cases, the laparoscopy is completed as follows. Remove
the ancillary ports, examining the incisions internally for bleeding. Then
remove the laparoscope and allow the intra-abdominal gas to escape through
the sleeve. Take the patient out of Trendelenburg position in order to optimize
the decompression of the pneumoperitoneum. Close the small lower abdominal
incisions with non-absorbable suture to be removed in 5-7 days. It is wise
to place an absorbable fascial suture in the larger >10 mm umbilical incisions
followed by a cutaneous non-absorbable suture.
Indication for diagnostic laparoscopy
1. Infertility. This is one of the most common indications for
diagnostic laparoscopy. A variety of pertinent diagnosis my be determined
at laparoscopy these include:
- adhesions- evidence of prior pelvic infection
- Structural abnormalities of the uterus, including congenital developmental
abnormalities (such as a bicornuate or unicornuate uterus), and fibroids.
- Endometriosis
- Fallopian tube occlusion. A diagnostic laparoscopy may clarify the
diagnosis and treatment prior to reconstructive surgery.
2. Chronic pelvic pain. The systematic evaluation of the abdomen
and pelvis provided by this relatively benign surgery can provide key diagnostic
information in the evaluation of a woman with chronic pelvic pain. In particular,
the laparoscopy my reveal adhesions or endometriosis not visible by other
diagnostic techniques.
3. Chronic Pelvic Inflammatory Disease (PID). It is essential
to carefully inspect the liver and diaphragm when considering this diagnosis.
4. Endometriosis. The appearance of endometriosis varies and it
is important that the laparoscopist is aware of the spectrum that one might
see during a laparoscopy. Early endometriosis may appear as clear vesicles
before progressing to red plaques and eventually black plaques. An intra-operative
biopsy will confirm the diagnosis.
Indications for an urgent diagnostic laparoscopy
1. Acute Pelvic Inflammatory Disease. If the diagnosis cannot
be clearly made by the clinical presentation, a diagnostic laparoscopy may
be useful the confirm this diagnosis.
2. Ectopic Pregnancy. Today, a laparoscopy for ectopic pregnancy
often not only provides the diagnosis, but also allows for the immediate
surgical treatment.
3. Torsion of a tube or ovary. This is often a difficult diagnosis
to establish. Echography rarely provides a clear diagnosis. Again laparoscopy
can both diagnose and treat this condition.
Contra-indications to laparoscopy
Absolute contraindications
- A large abdominal mass such as a fibroid or ovarian cyst
- An irreducible external hernia. A laparoscopy in this situation
could enlarge the hernia sac and make the condition worse.
- Hypovolemic shock.
- Medical problems such as cardio-respiratory failure, obstructive
airway disease, or a recent myocardial infarction.
- An inexperienced surgeon or a lack of proper equipment.
Relative contraindications
- Multiple prior abdominal incisions
- Morbid obesity. The difficulty in creating the pneumoperitoneum
may be overcome by introducing the Veress'' needle through the posterior
vaginal fornix.
- Local skin infections may require that the locations for the abdominal
incisions be altered.
- Generalized peritonitis
- Intestinal obstruction or ileus. This is a relative contra-indication
because of the increased risk of bowel perforation upon entry of the
Veress'' needle or trocars.
- Coincidental medical conditions such as ischemic heart disease,
blood dyscrasias or coagulopathies.
Ancillary instruments
Forceps
A wide range of forceps are available for laparoscopic use. It is less
important to have a wide range of forceps than to have perfected the use
of one or two. It is important to have at least one of each, an atraumatic
forceps and a forceps with teeth for stronger traction.
Scissors
Scissors which pass through a 5 mm port are sufficient for general dissection.
Microscissors may be preferable for adhesiolysis close to the fimbriae or
in other delicate locations. It is important that one of the blades is fixed
to allow gentle traction to be applied before cutting.
Laser
The laser will precisely destroy tissue. Both rigid and flexible systems
are available.
Sutures and clips
Sutures
Techniques for tying and applying will be discussed
in later chapters. In general there are two suturing techniques that are
used in laparoscopic surgery. In the first the knot is tied within the abdomen.
In the second the knot is tied extracorporeally. Suturing equipment includes:
a needle holder, grasping forceps, knot pusher, and needles which can be
passed through a 5 mm port.
Ligatures
Ligatures are most easily applied by using a prepacked
modified Roeder loop introduced through the standard 5mm cannula.
Clips and Staples
Clips and staples my be invaluable for obtaining hemostasis. Instruments
are also available which will apply up to three rows of staples on either
side of the line where an incision is to be made. A blade contained within
the instrument makes the incision. These instruments are disposable and
expensive.
Although a wide range of equipment exists for performing laparoscopic
surgery, it is important to master the use of the basic instruments and
appreciate their full potential before expanding to the use of more complicated
devices.

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Edited by Aldo Campana,
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