1. Electro surgery in Gynaecology
Dr Yogesh Nikam
Gynaecologist
Laparoscopic & Robotic Surgeon
MBBS, FRANZCOG, Master of Surgery (Obstetrics & Gynaecology)
Diploma in Advanced Endoscopic Surgery, Germany
Diploma in Gynaecological Endoscopy, BEAMS
Sydney West Advanced Pelvic Surgery, AU
VMO Norwest Private | Westmead Private | SAN Hospital
VMO Westmead Public | Staff Specialist (O&G), WSAHS
Senior Lecturer – UWS & Sydney University

2. History “Heat cures when everything fails” …Hipocrates.
Albucasis (980BC) used hot iron to stop bleeding.
Then followed use of electrical current on a metallic element…. just burns the tissues.
But modern electro surgery or “Surgical Diathermy” entails passage of high frequency electrical current through tissues.
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3. History
Earliest recorded use of this technology was by Arsenne d’ Arsonval in1893.
However extensive use of electro surgery in brain surgery by Harvey Cushing & William T. Bovie and their publication in 1925 promoted Electrosurgery.
They described three distinctive effects
Desiccation
Cutting
Coagulation
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4. Electro cautery and Electro surgery
Direct current through a high resistance metallic conductor
It is essentially application of heat and burning of tissue
Electro surgery
High Frequency Alt. Current through living tissue
Manipulation of electrons to produce heat within the cells to destroy the tissue
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5. Basics of Electricity Two types of Current- Direct Current (DC)
Alternating Current (AC)
DC flows continuously in one direction
AC flows in two directions, first increasing to a maximum in one direction & then increasing to a maximum in the opposite direction in a sinusoidal wave form.
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6. Basics of Electricity Alt.Cur. has a positive & a negative peak.
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7. Alternating Current
Alt.Current can be generated in Three types of wave form:-
Continuous / Uninterrupted / non-modulated wave form (CUT) :-
Produced by continuous delivery of energy
Interrupted / Modulated / Dampened / Varied wave form (Coagulation):-
when energy is delivered only 10% of the time
Blended wave forms:-
Produced by delivering energy at variable intervals, which can be controlled / varied thus producing both effects
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8. Alternating Current Continuous / Uninterrupted / non-modulated
CUT
Continuous / Uninterrupted / non-modulated
Produced by continuous delivery of energy
Current flows 100% of the time the pedal is pressed
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9. Alternating Current
COAG
COAGULATION- Interrupted / Modulated / Dampened / Varied wave form
current is delivered only 10% of the time
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10. Alternating Current Blended wave forms:-
Produced by delivering energy at variable intervals, which can be controlled / varied thus producing both effects
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11. The Machine (Generator)
It produces the required type of electricity in the patient circuit by induction from the supply line.
It has been undergoing constant improvement.
1st. Generation- Tungsten contacts.
2nd.Generation- Valve Generators.
3rd. Generation- Transistor technology.
4th. Generation- Digital Electronics technology.
Latest- Microprocessor controlled diathermy,
User programmable, auto functions, error detection, safety alarms & cut offs.
Constant power delivery
Under water application, soft & spray coagulation and bipolar cut possible.
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12. Effect of Electricity on Living Tissue
Electrolytic Effect
Faradic Effect
Thermal Effect
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13. Electrolytic Effect
Produced by DC/ AC of very low frequency (<5kHz).
Electrolytic effect used in current induced drug transport…ophthalmology.
Undesirable in HF Electrosurgery
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14. Faradic Effect Produced by AC of >20 kHz
Stimulation of nerve & muscle cells – Undesirable
Can be avoided by using current of >300kHz
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15. Thermal Effect Produced with AC >300kHz
At this frequency Electrolytic & Faradic effect are eliminated
Tissue gets heated leading to three possibilities, depending on-
Current density,
Duration of application &
Specific resistance of the tissue.
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16. Thermal Effect: - Possibilities
Electrosurgical Cutting with / without Coagulation
Desiccation
Coagulation / Fulguration
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17. Thermal Effect: - Possibilities
Tissue Necrosis Starts
700C
Coagulation begins with protein denaturation.. ”white coagulation”
900C
Cells loose water content, tissues dehydrate but architecture is preserved…..desiccation
1000C
Vaporization of boiled water starts…cells burst
2000C
Carbonization starts…black eschar
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18. Electrosurgical Cutting
HF electricity raises tissue temperature very rapidly
Very rapid heating of cells
No time for intra or extra cellular fluid evaporation
Steam formation-Pressure-Explosive bursting of Cells
With continuos current only cutting
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19. Electrosurgical Desiccation
Tissue is gradually heated
Water is slowly driven out
Cell plasma coagulates
Cut blood vessels shrink
Bleeding stops
Can be done with Needle electrode or bipolar Coagulating Forceps.
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20. Electrosurgical Desiccation
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21. Bipolar Diathermy
Current flows locally through a small portion of tissue between two electrodes of the bipolar forceps
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22. Bipolar Diathermy Advantages Disadvantages
Technique is precise & safe for the patient.
Preferred in endoscopic surgery.
Unintentional burns avoided.
Causes less disturbance to other electronic equipments connected to the patient.
Disadvantages
Only small amount of tissues can be handled.
Cutting possible only with microprocessor controlled machine.
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23. Monopolar Diathermy Patient plate is required.
High frequency current flows from the active electrode through the patient’s body to the patient plate.
It produces heat in the tissues proportional to the electrical resistance of the tissues and the current density.
Fatty tissues have a high resistance.
Electrosurgical Cutting with / without Coagulation and Desiccation / Fulguration all are possible.
Patient plate is required.
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24. Patient Plate
It is the negative pole / passive electrode through which the current returns to the machine after passing through the patient.
The current density at the patient plate is inversely proportional to the contact area.
A 50% decrease in contact area near the patient plate will produce two fold increase in current intensity and a four fold increase of heat.
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25. Patient Plate
Hence the Patient plate should be as large as possible.
It should be applied to a wide area of electrically more conductive tissues like muscles.  
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26. Patient Plate
Current does not flow uniformly to the patient plate.
Its density is higher at the corners and edges of the patient plate nearer to the the active electrode.
Hence the patient plate should be placed such that the longer edge points to the active electrode.  
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27. Patient Plate
It should make maximum and complete contact with the electrically conductive surface of the body to avoid burns.
Metal plates not to be used. Large Silicon rubber plates should only be used.
Simple patient plates are not so simple. 
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28. Conclusion Modern diathermy is a versatile & useful surgical tool.
Advancements in the technology has opened up many new vistas in treatment.
Its proper & judicious use can not only benefit the patients but also will make the surgery more efficient, comfortable and simple.
However utmost care has to be taken during its use so as to avoid catastrophes.
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29. Electrosurgical Injuries
Secondary to thermal injuries
Easily missed at time of injury
Classified
Unintended thermal injury through the active electrode
Injury when the current is diverted to another path causing damage distant from the principal operative field
Injury at the site of the dispersive electrode
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30. Direct Coupling (out of view)
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31. Electrical Isolation(metal canula)
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32. Electrical Isolation(tissue)
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33. Sparking/Jumping
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34. Avoiding Electrosurgical Injuries
lower settings
Keep probe in camera field
Check instruments for insulation
Metal vs... Plastic Trocars
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35. Harmonic Benefits Minimal thermal tissue damage
Greater precision near vital structures
Less tissue charring and desiccation
Minimal smoke for improved visibility
Fewer instrument changes
no electric current is sent through the patient
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36. How does it work?
The electrical energy provided by the microprocessor-controlled Generator is converted into mechanical energy by the Hand Piece through a piezoelectric crystal system. The blade or tip of the instrument being used vibrates axially with a constant frequency of 55,500 Hz. The longitudinal extension of the vibration can be varied between 25 and 100 µ in 5 levels, by adjusting the power setting of the Generator.
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37. 3 possible effects: Cavitation Coaptation /coagulation Cutting
Cavitation is achieved by the formation of vapor bubbles at body temperature due to the rapid volume changes of the tissue and cell fluids, induced by the transmitted vibration to the tissues.
Coaptation /coagulation
joint application of pressure and ultrasound to the tissue fragments the protein compounds, leading to the adherence of collagen molecules at low temperatures
achieved at a temperature range of 37 °C to 63 °C
Cutting
locally applied energy acts for longer periods, the rise in temperature leads to denaturing of protein – coagulation, at a maximum temperature of 150°C
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38. ULTRACISION HARMONIC SCALPEL
Balance between Cutting and Coagulation Cutting speed and extent of coagulation are easily controlled and can be balanced by varying four factors:
Power
Blade sharpness
Tissue tension
Grip force/pressure
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39. Power Setting The Harmonic Scalpel generator has five power levels.
Increasing the power level increases cutting speed and decreases coagulation. In contrast, less power decreases cutting speed and increases coagulation.
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40. Blade Sharpness
Cutting speed is also a function of blade sharpness. The shear mode of the LCS cuts faster than the blunt mode; the blunt mode provides more coagulation, assuring coagulation when vascular tissue or vessels are encountered.
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41. Tissue Tension
More coagulation can be achieved with slower cutting when tissue tension is reduced. Increased tissue tension leads to faster cutting with less coagulation.
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42. Grip Force/Pressure
Grip force, or pressure, is another factor controlling the balance between cutting and coagulation. Application of a gentle force, or light pressure, achieves more coagulation with slower cutting. A firmer grip force achieves less coagulation with faster cutting.
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43. Hand piece of harmonic
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44. Harmonic in action
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Courtesy : Ethicon Website

45. Monopolar in action in a da Vinci Robotic Surgery
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46. Bipolar in action in a da Vinci Robotic Surgery
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47. In summary
In monopolar surgery, electrical current goes through the patient to complete the current cycle, while
In bipolar surgery, the current only goes through the tissue in between the two electrodes of the instrument.
The cut mode on the electrosurgical unit generates a continuous, low voltage current concentrating the energy over a small area.
The coagulation mode on the electrosurgical unit generates an interrupted, high voltage current dispersed over a large surface area
Fulguration and vaporization are non-contact methods of monopolar electrosurgery, while desiccation/coagulation is a direct contact method of monopolar electrosurgery.
Vaporization results from rapid heating in the cut mode with intense vibration and heat within the cells, which causes the cell to explode and form smoke (plume)
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48. Fulguration is caused by an interrupted current (coagulation mode), causing slower tissue heating and less focused tissue effect.
The cut mode is preferred when thermal spread is undesirable, such as when the electrosurgical device is in close proximity to vital structures.
The coagulation mode is better suited for fatty tissue and scar tissue and when fulgurating a large surface area with superficial bleeding.
A return electrode monitoring system and active electrode monitoring are important safety tools during monopolar electrosurgery.
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49. Bipolar electrosurgery is ideal when dealing with vascular areas or large blood vessels, such as the uterine artery.
The disappearance of water vapor is a good guide for deciding when to stop the application of bipolar electrosurgical energy. Newer bipolar devices measure tissue impedance & stop the generator once the tissue is desiccated
The Ligasure had the best overall performance with the highest burst pressure, fast sealing time, low thermal spread, and low smoke production. Can be used on bigger vessels upto 7mm.
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50. Finally, Dr Andrew Bril put aptly at the AAGL conference
The PK has a fast sealing time, high smoke production, variable and sometimes extremely low burst pressures.
The Harmonic Ace is a mechanical way to seal vessels. It has the lowest thermal spread and smoke production, but is slow and has low mean burst pressures. It is best used to seal vessels of 2-5mm of diameter.
A knowledgeable surgeon using an appropriate instrument at precise location for just adequate time is the best prevention against electrosurgical injuries.
Finally, Dr Andrew Bril put aptly at the AAGL conference
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51. It's not the magic wand, it's the magician! THANK YOU
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