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Electro surgeryin Gynaecology
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History Heat therapy known since antiquity
Heat cures when everything fails Hipocrates.
Albucasis (980BC) used hot iron to stop bleeding.
Then followed use of electrical current on a metallic
element.
This method just burns the tissues.
But modern electro surgery or Surgical Diathermy is
a recent technology, which entails passage of highfrequency electrical current through tissues.
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History
Earliest recorded use of this technology wasby Arsenne d Arsonval in1893.
However extensive use of electro surgery in
brain surgery by Harvey Cushing & William T.Bovie and their publication in 1925 promotedElectrosurgery.
They described three distinctive effects -
Desiccation Cutting
Coagulation
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Electro cautery and Electro surgery
Electro cautery Direct current
through a high
resistance metallicconductor
It is essentiallyapplication of heat
and burning of tissue
Electro surgery High Frequency Alt.
Current through
living tissue Manipulation of
electrons to produceheat within the cells
to destroy the tissue
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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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Basics of Electricity
Alt.Cur. has a positive & anegative peak.
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Alternating Current
Alt.Current can be generated in Threetypes of wave form:-1) Continuous / Uninterrupted / non-modulated wave
form (CUT) :-
Produced by continuous delivery of energy
2) COAG- Interrupted / Modulated / Dampened /Varied wave form:-
when energy is delivered only 10% of the time
3) Blended wave forms:-
Produced by delivering energy at variable intervals,which can be controlled / varied thus producing botheffects
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Alternating Current
1) Continuous / Uninterrupted / non-modulated(CUT) wave form:- Produced by continuous
delivery of energy
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Alternating Current
2) COAG- Interrupted / Modulated / Dampened /Varied wave form:-. when energy is deliveredonly 10% of the time
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Alternating Current
3) Blended wave forms:- Produced bydelivering energy at variable intervals, whichcan be controlled / varied thus producing
both effects
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The Machine (Generator)
It produces the required type of electricity in thepatient 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 cutpossible.
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Effect of Electricity on Living Tissue
Electrolytic Effect Faradic Effect
Thermal Effect
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Electrolytic Effect
Produced by DC/ AC of very low frequency(
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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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Thermal Effect
Produced with AC >300kHz
Tissue gets heated leading to three
possibilities, depending on-
Current density,
Duration of application &
Specific resistance of the tissue.
This is the effect for clinical use.
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Thermal Effect: - Possibilities
Electrosurgical Cutting with / withoutCoagulation
Desiccation
Coagulation / Fulguration
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Electrosurgical Cutting +/- Coagulation
Very rapid heating of cells
No time for evaporation
Steam formation- Pressure-
Cells burst
With continuos current only
cutting
With blended current - both
cutting & coagulation.
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Electrosurgical Desiccation
Tissue is gradually heated
Water is slowly driven out
Cell plasma coagulates Cut blood vessels shrink
Bleeding stops
Can be done with MP Ball / Needle electrodeor bipolar Coagulating Forceps.
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Electrosurgical Desiccation
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Bipolar Diathermy
Current flows locally
through a small portion
of tissue between twoelectrodes of the
bipolar forceps
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Bipolar Diathermy
Advantages 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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Monopolar Diathermy
High frequency current flows from the activeelectrode through the patients body to the patient
plate.
It produces heat in the tissues proportional to theelectrical resistance of the tissues and the currentdensity.
Fatty tissues have a high resistance.
Electrosurgical Cutting with / without Coagulationand Desiccation / Fulguration all are possible.
Patient plate is required.
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Patient Plate
It is the negative pole / passive electrodethrough which the current returns to themachine after passing through the patient.
The current density at the patient plate isinversely proportional to the contact area.
A 50% decrease in contact area near the
patient plate will produce two fold increase incurrent intensity and a four fold increase ofheat.
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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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Patient Plate
Current does not flow uniformly to the patientplate.
Its density is higher at the corners and edges of
the patient plate nearer to the the activeelectrode.
Hence the patient plate should be placed such
that the longer edge points to the activeelectrode.
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Patient Plate
It should make maximum and complete contactwith the electrically conductive surface of the
body to avoid burns.
Metal plates not to be used. Large Siliconrubber plates should only be used.
Simple patient plates are not so simple.
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Diathermy in Gynaecology- General
Use
During surgery ( Open & Laparoscopic) for Cutting &
Haemostasis.
Cutting is more precise.
Haemostasis is better achieved. Can be used in LSCS. No effect on the fetus.
Take care while working near vital structures.
Apply the point first , then switch on the current. Monopolar & or Bipolar can be used.
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Diathermy in Gynaecology- Specific Use
Benign Cervical Lesions-
CIN (LEETZ / LEEP)-
Tubal Sterilisation-
Ovarian Drilling in PCOD-
Endometriosis-
Laparoscopic Myolysis- Hysteroscopic surgery- TCRE, sub mucus
Myoma, Septum Resection
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Electro surgery for Benign Cervical
Lesions
Coagulation / Desiccation / Cutting can bedone as the case may be, using Monopolar
diathermy in the following conditions.
Erosion & Chronic Cervicitis - Avoidendocervix
Mild degree Cx. Tears
Amputation
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Electro surgery for CIN Known as Large Loop Excision of the Transformation
Zone (LLETZ) or LEEP (Loop Electrosurgical ExcisionalProcedure).
A wire loop electrode on the end of an insulatedhandle is powered by an electrosurgical unit.
The current is designed to achieve a cutting and acoagulation effect simultaneously.
Power should be sufficient to excise tissue withoutcausing thermal artifact.
The procedure can be performed under localanalgesia.
Treatment success reported varies from 91% to 98%.
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Electro surgery for Tubal Sterilisation
Tubal sterilisation is usually done either by
mini- laparotomy 0r laparoscopy with almost
equal results.
But laparoscopy requires more sophisticated
and expensive equipment and greater skills.
Laparoscopic sterilisation should usually be
done by a single puncture and use of
monopolar coagulation as described by
Wheeless [Wheeless 1992].
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Female Sterilisation methods
0
5
10
15
20
25
30
35
40
clip bipolar interval ring mono PPTL overall
Method
24.8
7.5
17.7
36.5
20.1
7.5
18.5
Probability
per
1000procedures
Ten-Year Cumulative Probability ofPregnancy (per 1000 procedures)
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Electro surgery for PCOD For PCOD, Laparoscopic Ovarian Drilling (LOD) by Diathermy is
cost effective than Laser vaporization. It is done by passage of 40 W current for 4 seconds in 4 places
on each ovary with a monopolar needle.
Advantages of ovarian drilling-
Sensitizes the ovary to F.S.H. Less monitoring than Gonadotrophin therapy.
Unifollicular growth, No risk of OHSS and multiple pregnancy.
Low rate of abortion.
One treatment may result in many ovulatory cycles.
Ovulation rate 70 80% in failed C.C. cases, Pregnancy rate 60%
To reduce periovarian adhesions liberal peritoneal lavageshould be done. Early second look laparoscopy and adhesiolysismay be required.
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Electro surgery in Endometriosis
During surgery for endometriosis, small and
multiple lesions on the peritoneum are better
dealt with electrocoaglation.
Care should be taken while working near vital
structures.
Though both monopolar and bipolar may be
used, bipolar is safer and preferable.
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Electro surgery for Myoma
Myolysis - involves delivering electric current
via needles (Monopolar) to a fibroid at the
time of laparoscopy.
It offers a better alternative to myomectomy
with minimal blood loss to deal with myomas
particularly multiple ones.
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Hysteroscopic Electro surgery-
Endometrial ablation - Tran Cervical Resectionof Endometrium (TCRE), with wire loop orroller ball is a simple office procedure.
It can be the first line of surgical treatment inMenorrhagia (DUB) and may avoid hysterectomy.
Other hysteroscopic electrosurgicalprocedures are -
Electrovaporisation of sub mucus Myoma.
Septum Resection
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Conclusion
Modern diathermy is a versatile & usefulsurgical 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 surgerymore efficient, comfortable and simple.
However utmost care has to be taken duringits use so as to avoid catastrophes.