Participants should be able to perform,
with confidence, basic procedures such as laparoscopic cholecystectomy or
laparoscopic appendicectomy under the initial supervision of an experienced
laparoscopic surgeon.
They should also be able to act as proficient
first assistant at laparoscopic procedures.
1.2 Objectives
Our objectives are that the student should be
able to:
Identify and use basic endoscopic equipment.
Prepare the patient.
Induce a pneumoperitoneum using a safe technique.
Perform a systematic laparoscopic examination
and recognise abnormalities.
Master the techniques for safe instrumentation.
Understanding the principles and hazards
of electrocautery.
Understand the factors governing port placement
and retraction.
Tie off structures using clips and performed
loop.
Be familiar with procedures for gall bladder
extraction.
1.3 Patient information
It is very important that all patients undergoing
laparoscopic surgery understand that:
you cannot guarantee to perform their operation
laparoscopically - only by the safest method for them at the time of surgery.
they will have several small incision.
even though the incisions are small all
operations have associated risks.
they may have post operative shoulder tip
pain.
they may have to stay in hospital longer
than expected if things are not straight forward.
consequences of open surgery will follow,
should it become necessary.
1.4.Theatre Staff and Preparation
The theatre must naturally be able to supply
the relevant equipment and instruments for a procedure.
In addition appropriate instruments should
be immediately available to cope with emergency complications such as major
bleeding.
Spare bulbs for the light source and a spare
gas cylinder should be available.
This type of surgery places great reliance
on technology. If you can begin your laparoscopic experience in a theatre
where everyone is familiar with their part in the proceedings it will be to
your advantage.
2. PREPARATION OF THE PATIENT
For laparoscopic cholecystectomy :
Prophylactic antibiotics.
A standard anaesthesia with appropriate
monitoring.
The patient should empty the bladder just
prior to the procedure. Avoid unnecessary catheterisation.
A naso-gastric tube is used to deflate the
stomach.
The patient is placed supine.
As the patient will be tipped during the
procedure appropriate measures to ensure their safety are instituted.
3. BASIC INSTRUMENTATION
Most endoscopic procedures require a mixture
of sharp and blunt techniques, often using the same instrument in a number of
different ways.
Endoscopic surgery is controlled also entirely
by vision alone.
Any loss of view will result in loss of
control and hence reducing safety.
Haemorrhage, even to a minor extent, tends
to obscure the operative field and consequently is to be avoided.
This means that vessels of a size that in
open surgery could be divided without particular attention need to be secured
prior to division when working endoscopically.
Dissection must be more meticulous to proceed
smoothly.
Magnification of tissues by the endoscope
may initially confuse an inexperienced surgeon as to the severity of the bleeding.
A moderate bleed can appear torrential but
an inexperienced endoscopic surgeon is well advised to convert should he have
any doubt about his ability to control the situation expeditiously.
3.1.1. Techniques to assist in
control of bleeding
Pressure on the area supplied by a retracting
grasper pressing neighboring tissue on to the area.
Pressure from a pledget.
Pressure and suction / irrigation with the
sucker.
Picking up the vessel with a grasper.
3.1.2. Methods of securing haemostasis
Coagulation
Loop
Ligature
Clipping
Pressure
Other agents
4. ACCESS
4.1.Pneumoperitoneum and Trocar
Insertion
One of the most dangerous complications of endoscopic
surgery is bleeding due to accidental vessel damage during this initial stage.
Establish and follow a safe routine. A closed technique or open technique can
achieve access.
4.2.Closed Access
4.2.1.Veress needle insertion
The standard method of insufflation of the
abdominal cavity is via a Veress needle inserted through a small skin incision
in the infra umbilical region.
The Veress needle consists of a sharp needle
with an internal, spring loaded trocar. The trocar is blunt ended with a lumen
and side hole.
CO2 is use for insufflation as
it is 200 times as diffusible as O2, is rapidly cleared from the body by the
lungs and will not support combustion. Insufflation "retracts" the anterior
abdominal wall exposing the operative field.
The insufflator used should monitors insufflation
pressure, gas flow rate and volume of gas consumed. It automatically maintains
the intra-abdominal pressure at the predetermined level.
4.2.2. Trocar Insertion
The first trocar and cannula inserted is
an 11 mm / 6mm trocar to accommodate a 10 mm / 5mm telescope and leave sufficient
space in the trocar for rapid gas insufflation if required.
Following insufflation, the Veress needle
is removed and the trocar inserted with care at the same point, using a blind
technique (see Step by step). The telescope can then be introduced.
Subsequent trocars are inserted under direct
vision at locations appropriate for the procedure and to the anatomy of the
individual.
Different sized converters (gaskets) are
available with some makes of disposable cannulae to maintain the gas seal.
4.2.3.Step by step Veress Needle
insertion
Check and set the insufflator pressure level
and flow rate.
Initial flow rates should be set at 1-2
litre/min.
An initial pressure setting of 10.0 - 15.0
mmHg is recommended.
Connect up gas supply to Veress needle.
Check gas flow, needle patency and spring
loaded central blunt stylet
Palpation test : Assessment abdominal wall
thickness by palpation with the fingers down to the aorta.
Skin incision.
Tense abdominal wall and insert needle :
Hold the needle at a point along its shaft at a distance from the tip that
equates with that estimated by palpation as the abdominal wall thickness.
The other hand holds up the abdominal wall, providing counter tension as the
needle is "threaded" in. You should be able to feel the needle puncture two
distinct layers. Once the sharp tip enters the peritoneal cavity, the spring-loaded
blunt stylet is released with an audible (palpable) click.
Check that the needle is
in the correct position. A number of tests exist to confirm correct positioning
of the needle tip :
Aspiration: uses a saline
filled syringe.
Saline drop test: uses
a drop of saline in the Veress needle hub.
Negative pressure test:
The insufflator dial should be negative or less than 5 mm. Hg.
Early insufflation pressures: the insufflation
pressure should be low and the flow should be very near the maximum
flow you have set.
The number of passes required should be recorded.
If a small amount of blood is
aspirated, reinsertion is justified.
If
large amounts of blood escape up the needle laparotomy is indicated.
If bowel content is aspirated the needle is withdrawn and
reinserted in another location.
Subsequent inspection and adequate treatment for bowel injury
is mandatory.)
Insufflate. After a minimum of 1 litre of
gas has been insufflated and needle position has been confirmed the rate may
be increased for more rapid filling. Periodic checks should be made of symmetric
distension and abdominal resonance.
Close the gas tap on the needle and withdraw
it, once the desired pressure has been reached.
4.2.4. Step by step insertion of
first cannula
Enlarge the sub umbilical skin incision.
Check trocar and cannula.
Insert trocar and cannula into abdominal
cavity and immediately remove trocar. The trocar should be inserted in a direction
parallel to the aorta and pointing towards the centre of the pelvic cavity.
Power should be applied from the wrist and not the shoulder. The index finger
should be used along the side of the cannula to limit penetration.
Connect the gas supply.
Insert the telescope.
The telescope is pre heated. A stainless steel
vacuum flask with warm sterile saline, which stands on the instrument trolley,
is used but other arrangements can be made. This helps to prevent misting of
the lens on insertion into the warm, moist abdominal atmosphere. Should the
lens become smeared during the procedure it can be dipped in saline and wiped
with a gauze swab. Wiping on organs such as the liver is not encouraged as it
leads to protein build up on the lens.
Inspect
the abdominal cavity for
Damage
Adhesions
Multiple pathology
Feasibility of surgery
4.3. Open access
A sub-umbilical incision is made.
Fascia is visualised and grasped with tissue
forceps.
Under vision, the fascia is incised and
the cut edges are grasped with tissue forceps.
Fascial sutures are taken under vision.
Blunt Hasson's trocar 11mm / 6mm is introduced.
Position checked by early insufflation pressures.
5. COAGULATION
Electro-coagulation using HF current may be
monopolar or bipolar. Bipolar is safer in dissections were space is restricted.
When a monopolar system is used the safest form is SOFT coagulation. This setting
maintains the voltage below 200 V so that sparks are not generated. Soft coagulation
is recommended for endoscopic use. It may be applied by insulated graspers,
hook, spatula or scissors.
5.1. Safety Considerations in Minimal
access surgery
Click here to see Video Clip on "Monopolar Hook Diathermy" Modem or Broadband
There are three ways by which current can leak
into undesirable situations:
5.1.1. Direct coupling
This occurs when the diathermy is activated
when the active electrode is near a metal instrument. The second instrument
becomes energised. This energy will seek a pathway to complete the circuit to
the patient electrode. Neighboring structures like bowel can become injured.
DO NOT ACTIVATE THE GENERATOR WHILE THE
ACTIVE ELECTRODE IS TOUCHING OR IN CLOSE PROXIMITY TO ANOTHER METAL OBJECT.
5.1.2. Insulation failure
Faulty instruments cause this. Insulation "breaks"
can cause "leaks". This is more common when high voltage coagulation current
is used.
ALWAYS CHECK INSTRUMENTS FOR INSULATION
BREAKS. MINIMISE THIS DANGER BY KEEPING THE COAGULATION CURRENT SETTING TO
BELOW 200V.
5.1.3. Capacitance coupling
Capacitance occurs when a non-conductor of electricity
separates two conductors. This typically occurs between an insulted instrument
and a metal cannula. An electrostatic current field is created and it can induce
current in the metal cannula. Plastic cannula does not eliminate this problem
completely as the patient's body can act as a conductor. The worst situation
occurs when a metal reducer is used in a plastic cannula!
USE ALL METAL CANNULA SYSTEMS. INVEST
IN LATEST TECHNOLOGY- RECENT DIATHERMY MACHINE WHICH COME WITH ACTIVE ELECTRODE
MONITORING, WHEREIN EXCESS STRAY CURRENT AUTOMATICALLY SWITCHES THE GENERATOR
OFF.