Haemostasis is very important in laparoscopic surgery. Vessel sealing with energy devises play a major role in keeping the surgical field clear. Energy devices are also used for tissue sealing and transection. Despite never types of energy devises electro-surgery is still very popular in gynaecological laparoscopy. Desiccation, dissection, and coagulation are the main effects of electro-surgery that are used for various purposes. Higher thermal injury with monopolar devices lead to the invention of bipolar devices with less tissue damage. Ligasure, pk gyrus, ENSEAL are some of the more advanced bipolar devices. Ultrasonic devices have the capability of coagulation and cutting tissues. During the process it can produce significant thermal injury. Thunderbeat combines bipolar and ultrasonic energy for coagulation and cutting respectively for more precise effects. Laser devices emit a beam of photons with a high degree of spatial and temporal coherence with tissue effects depending on the time of exposure and power density. CO2, Argon, Nd: YAG, KTP-532 are different laser types with different properties. Plasma is the fourth state of matter following solid, liquid and gas. Argon neutral plasma (System 7550TM ABC, Cardioblate) can produce energy in 3 forms including light, heat and kinetic energy. Laser and plasma energy are gaining more popularity for endometriosis surgery due to its localised effects and better preservation of ovarian follicles.
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Use of energy devices in laparoscopy.pptx
1. Use of Energy Devices in
Laparoscopy
Indunil Piyadigama
Consultant Obstetrician and Gynaecologist
Base Hospital Kahawatta
2. Functions needed for an operative
laparoscopy
Haemostasis
(vessel
sealing)
Tissue sealing
Tissue/ vessel
transection
3. Electrosurgery
• This is the use of alternative current for
the purpose of cutting and coagulation
• Electrical energy is the most commonly
used energy in operations
• In 1891, D’Arsonoval showed that it was
possible to pass high frequency
alternating current (>20 kHz) through the
body without causing an electric shock
• 1926 first application of electrosurgery
was done with the electrosurgical
generator designed by William Bovie
4. Principles of
electrosurgery
• 3 basic components of electrosurgery are
electrosurgical generator, active and passive
electrode
• Circuit must be completed
• Electrosurgical effects are brought in the target
tissue through the conversion of electrical
energy into heat
• Heat = Current2 x Voltage x Time
• Current (amps) = Voltage(Volts) /
Resistance(Ohms)
5. Tissue effects of electrosurgery
• Heat produces the desired effects at the tissue
34-440C
• Oedema and
tissue
inflammation
44-500C
• Enzyme
denaturation
50-800C
• Coagulative
necrosis
80-1000C
• Tissue
dessication
>1000C
• Water
inside the
cell
evaporates
• Higher temperatures result in vaporization due to hydrocarbon combust
• Coaptation is vessel wall sealing due to denaturation and renaturation of
proteins
6. Cutting
Low voltage and high current waveform delivered
continuously
Results in a rapid temperature elevation more than 100
°C
Explosive vaporization of intracellular fluid and ionization of the gas released produces a clear
cutting action dividing the tissue with minimal lateral spread
7. Superficial Coagulation or fulguration
6% of the time high
voltage low current
waveform
This is possible with
monopolar when the
electrode is not
touching the tissues
Produces sparks
resulting in slow
temperature increase
This results in protein
denaturation and
formation of coagulum
but greater lateral
thermal spread
8. Deep coagulation or desiccation
Desiccation can be achieved
with either the cut or
coagulation mode by contact
of the electrosurgical device
with the tissue and no spark
formation
Tissue is heated and the
water in the cell boils to
steam
Results in drying out of the
cell
9.
10. Other factors influncing tissue effects
Size and
shape of
electrode
Time of
electric
application
Tissue
resistance
Whether the
electrode
touches the
tissue or not
11. Monopolar electrosurgery -
Specific issues
• Alternative site burns – Return
electrode monitoring to avoid this
• Insulation failure
• Direct coupling
• Capacitative coupling
13. Bipolar vs Monopolar
Advantages
• Overall damage is twice less
• Reduced depth of penetration
• Less smoke generation
Disadvantages
• Since the outer layers of tissue
desiccate, the current flow
increases and lateral spread occurs
to almost 3-4 mm
• Also coagulation may cease before
it is completed and for that reason
bleeding may result
• A significant problem with bipolar
electrodes is tissue sticking
14. Advanced bipolar devices
• Bipolar forceps with advanced variables
• Stronger and more uniform tissue compression
• Unique ways of controlling the delivery of energy and heat
• Electro surgical generator uses controlled tissue feedback response systems that senses
tissue impedance in order to continuously adjust the voltage and current generated by
the unit
• Can seal vessels up to 7mm diameter
• Systems also inform the surgeon with an audio signal that vessel sealing has been
achieved minimizing this way lateral thermal spread associated with prolonged device
activation
15. The increased temperature causes
denaturation of hydrogen bonds in
tissue proteins
The pulsatile energy delivered from the
feedback mechanism of the device
permits the tissue to cool
During this phase hydrogen bonds
reform with a different configuration
result in formation of a tissue glue
This seals the walls of the vessel
18. Ultrasonic devices
• Able to seal vessels and transect tissues
• Tissue effects are the same as those for bipolar devices
• However effects are produced without the passage of electrical current through the tissue
• Principle of ultrasonic energy is conversion of electrical energy into mechanical and
thermal energy via ultrasonic vibrations to achieve tissue transection and vessel sealing
• A piezoelectrode that convert electric energy to vibrating ultrasonic energy at frequencies
from 23 to 55 kHz
• The active blade vibrates over 50-100 μm at frequency of 55.5 kHz
• Tissue transection occurs as a result of mechanical friction between the oscillating device
shaft and the tissue
19. • Addition to mechanical friction there is cavitation effect
• During tissue vaporization the steam released from vaporized cells
expands existing tissue planes, assisting dissection. This is called
cavitation effect
22. Ultrasonic devices
Advantages
• Less tissue necrosis and charring
• Reduced lateral thermal spread
• Less smoke generation
Disadvantages
• Slower coagulation compared
with electrosurgery
• The tip of the active blade needs
to be always under vision and
never touch visceral organs
immediately after activation as
there is danger of serious
thermal damage due to high
temperatures
23. Combined
bipolar and
ultrasonic
devices
• The first device to integrate both ultrasonically generated frictional heat
energy and advanced bipolar energy in one instrument.
• It can rapidly cut and precisely dissect tissue while advanced bipolar
technology provides vessel sealing up to 7 mm diameter with minimal
thermal spread
24. Laser
• Laser devices emit a beam of photons with a high degree of
spatial and temporal coherence
• This is achieved by amplifying light of specific wavelength
• There are a number of different types of lasers: CO2, argon,
Nd: YAG, KTP-532 with different properties
• Advantages of laser are the accuracy of targeting tissues and
lack of lateral thermal spread
• In gynecology they are mainly used for endometriosis
ablation as they are not absorbed by unpigmented tissues
and thus abnormal tissues are preferably coagulated
25. Problems with laser
Always a concern about the possibility of
ignition of flammable materials
Accidental eye injuries Laser beams may also reflected by surgical
instruments in the operating field and
provoke injuries of nontargeted tissues
26. Argon neutral plasma (System 7550TM
ABC, Cardioblate)
• Plasma is the fourth state of matter after solid, liquid
and gas
• When energy is provided to a solid, it melts to form
liquid and then evaporates to form gas. If extra energy
is provided then gas is ionized and becomes plasma
which is unstable
• Plasma emits three types of energy
• Light that illuminates target area
• Heat that coagulates tissue and seal small vessels
• Kinetic energy that vaporizes tissues of various
densities including the fibrosis of deep
endometriosis
• It is mainly used for the treatment of endometriosis
because of better preservation of ovarian follicles
27. Tissue damage with energy devices
• All energy devices exert tissue effects with heat generation
• Temperatures above 42 °C may cause tissue damage
Device Temperature at the tip of the
instrument (Highest)
Time to cool down to 420C
Monopolar 100.10C (120) 55s
Harmonic Ace 71.30C (234) 38s
Bipolar and Ligasure 500C (100.5) 14s
2Kim FJ, Chammas MF Jr, Gewehr E, Morihisa M, Caldas F, Hayacibara E, Baptistussi M, Meyer F, Martins AC.
Temperature safety profile of laparoscopic devices: Harmonic ACE (ACE), Ligasure V (LV), and plasma trisector (PT).
Surg Endosc. 2008 Jun;22(6):1464-9. doi: 10.1007/s00464-007-9650-9. Epub 2007 Nov 20. PMID: 18027042.
1Sutton PA, Awad S, Perkins AC, Lobo DN. Comparison of lateral thermal spread using monopolar and bipolar diathermy, the
Harmonic Scalpel and the Ligasure. Br J Surg. 2010;97:428–433
28. Summary
• Electricity is used in majority of surgeries, and it is the oldest energy source in
surgery
• Monopolar devices passes a current through the patient with its own risks
• Bipolar, lasers and ultrasonic energy avoid the passage of electrical stray currents
trough the patient
• All these devices exert their action to the tissues through thermal energy
• Lateral thermal spread is always a concern of all these devices
• Understanding the device will make it safer and much more effective
• Overall energy devices eases operative surgery and reduces operative times