a well compiled ppt

1. DIATHERMY
&
SURGICAL DRAIN
DR MOHAMMD KAUSHAR
FCPS SURGERY RESIDENT (1ST YEAR) , MMTH

2. HISTORY OF DIATHERMY:
 Diathermy, which literally means "through Heat" is a
technique using high frequency energy to directly
heat deep seated tissues and produce a therapeutic
response.
 Diathermy was first used in 1907 by Nagelschmidt, a
Berlin Physician.

3. Fundaments of radiofrequency
electrosurgery
 CURRENT (I) =Flow of electrons past a point in circuit/unit time (Amperes
 CIRCUIT =Pathway for the uninterrupted flow of electrons
 VOLTAGE(V) =Force pushing current through the resistance, measured in
volts
 RESISTANCE(R) = Obstacle to the flow of current, measured in ohms
(impedance = resistance)
 POWER= amount of energy per unit time (P= V x I ) watts
 I= V/R (ohms law)

4. Electrosurgery
 Electrosurgery is a simple method of making surgical incisions,
controlling bleeding and destroying unwanted tissue cells by the
use of a high frequency “electrosurgical current”.
 Electrosurgical devices (Surgical Diathermy Machine) are frequently
used during surgical operations helping to prevent blood loss in
hospital operating rooms or in outpatient procedures.

5. Principles of Electrosurgery

6. Principles of Electrosurgery

8. Principles of Electrosurgery


10. Effects of modified waveforms in tissue

12. Surgical surgical Machine
 It is a dedicated medical therapeutic equipment
 cut, coagulate, desiccate, or fulgurate tissues
 Electrosurgical units/ generator- fxn
1)conversion of low frequency to RF output
2) adjustment of wattage and indirectly voltage
3)control of duty cycle

13. Block Diagram of Surgical
Diathermy

14. Electro -Surgery Techniques
Mono-polar technique
Bi-polar technique

15. Mono-polar technique

16. Some Basics of Monopolar
Surgery
 Diathermy currents (HFAC) may be generated by transistor circuits
and may include a range of protection.
 The frequencies used are typically in the range 0.5 to 3 MHz.
 Most versions have power output up to a few hundred watts.
 Higher power necessary for urology applications where the surgery
often takes place under water (in the bladder).
 Low power versions exist, sometimes called hyphenators, for excision
of warts, polyps, and skin flaps.

17. Bi-polar technique

18. Some Basics of Bipolar
Surgery
 Diathermy currents may be generated by valve or transistor
circuits and may include a range of protection and monitoring
systems.
 The frequencies used are typically in the range 0.5 to 3 MHz.
 Bipolar systems are available in which the heating currents only
flow between the two tips of special forceps.
 Bipolar systems are useful for fine work and when the patient has
a pacemaker which might malfunction in the presence of the very
large circulating high- frequency current.

19. ESU Electrodes

20. Types of ESU Electrodes
Active Electrode
Passive Electrode

21. Electrodes are connected to the RF power generator.
Switching on the high frequency current can be done
with a finger-tip switch in the electrode or a foot
switch.
Small size (thickness in mm (1mm) and wideness till
10 mm).
Active Electrodes

22. Active electrode for coagulation

23.  The amount of power delivered to the tissue
for a given ESU voltage depends on the active
electrode-to-skin resistance RE.
 RI: Internal resistance of active electrode
 RE: active electrode-to-skin resistance
 RB: Body resistance
 RR: Return electrode resistance
Active Electrode Resistance

24. Passive (Neutral, Return)
Electrode
 The function of the patient return electrode is to remove current
from the patient safely.
 A return electrode burn occurs when the heat produced, over
time, is not safely dissipated by the size or conductivity of the
patient return electrode.
 Two points are of practical importance:
(i) Sufficiently large contact area.
(ii) High electrical conductivity between the body and
electrode.

26. Patient Return Electrodes
Assessment of Pad Site Location
 Choose: -Well vascularized muscle mass
 Avoid: -Vascular insufficiency
-Irregular body contours
-Bony prominences
 Consider: -Incision site/prep area
-Patient position
-Other equipment on patient

27. Effects on Body Tissue
Cutting
Coagulation/Desiccation
Fulguration

28. Cutting
Cutting/Vaporization:
High current concentration at active electrode
causes intense heat in tissue (above 100c).

29. Coagulation
 Coagulation is the process by which h blood forms
clots. Every damaged blood vessel wall is covered
by a platelet and fibrin-containing clot to stop
bleeding and begin repair of the damaged vessel.

30. Desiccation
Desiccation is the state of extreme dryness, or the
process of extreme drying. A desiccant is a
hygroscopic (attracts and holds water) substance
that induces or sustains such a state in its local
vicinity in a moderately sealed container.

35. Fulguration

36. Electrosurgical Tissue Effects
 Variables Impacting Tissue Effect
Waveform
Power Setting
Size of Electrode
Time
Manipulation of Electrode
Type of Tissue
Eschar

39. Safety aspects in electro-surgical unit

40. cont,.

41. Avoid complications of lap.electrosurgery
Inspect insulation carefully
Use lowest possible power setting &low voltage waveform (cut)
Use brief intermittent activation vs. prolonged activation
Do not activate in open circuit & close proximity or direct contact
with another instrument
Use bipolar electrosurgery when appropriate

42. Cont.
Select an all metal cannula system as the safest choice.
Do not use hybrid cannula systems that mix metal with plastic
Utilize available technology, such as a tissue response generator to
reduce capacitive coupling or an active electrode monitoring system,
to eliminate concerns about insulation failure and capacitive coupling.

43. New advances
 Argon beamer-
 harmonic scalpel

44. Cont.
 Enseal ----Ligasure ( good vessel sealer 7mm) +
harmonic (good dissector)
 Thunderbeat --- harmonic + ligasure (bipolar) in
same devices

45. REFERENCES
 Society of American Gastrointestinal and
Endoscopic Surgeons (SAGES) LECTURE ON
FUSE (Fundamental Use of Surgical Energy
(FUSE)
 PRINCIPLES OF ELECTROSURGERY BY
COVIDIEN ( medical device company)

46. “
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THANK YOU