educational purpose

1. RDT Hospital,
Dept of Gen Surgery
Electrosurgery
Dr sumanth

2. Objectives
 Describe the principles of the ESU and purpose for its use
 Describe Monopolar & Bipolar ESU’s and associated
equipment
 Describe the types of dispersive electrodes (grounding
pads) and appropriate use, including proper anatomic
placement
 Identify special considerations for the use of the ESU

3.  Often “electrocautery” is used to describe
electrosurgery. This is incorrect.
 Electrocautery refers to direct current (electrons
flowing in one direction) whereas electrosurgery
uses alternating current.
 During electrocautery, current does not enter the
patient’s body. Only the heated wire comes in
contact with tissue.
 In electrosurgery, the patient is included in the
circuit and current enters the patient’s body.

5.  “Proper care & handling of electrosurgical
equipment is essential to patient and
personnel safety.”
 “Electrosurgery is used routinely to cut,
coagulate, dissect, fulgurate, ablate, and
shrink body tissue with high frequency
(i.e. radiofrequency) electrical current.”
AORN (2007) Standards, Recommended Practices, and Guidelines

6. History Lesson
 The first electrosurgical unit was
developed in 1926 by Dr. Harvey
Cushing (a neurosurgeon) and Dr.
William Bovie, a Harvard physicist
 The name “Bovie” has been
associated with electrosurgical units
ever since

7. Electrosurgery
 Involves using a high-
frequency electric
current to cut tissue
and coagulate bleeding
 The flow of electricity
requires a complete
pathway (circuit)

8. System components:
1. Generator (electrosurgical unit)
2. Inactive dispersive electrode
(grounding pad)
3. Active electrode (“Bovie” pencil)

9.  The electrosurgical generator is the source of the
electron flow and voltage.
 The circuit is composed of the generator, active
electrode, patient, and patient return electrode.
Pathways to ground are numerous
 but may include the OR table, stirrups, staff
members, and equipment.
 The patient’s tissue provides the impedance,
producing heat as the electrons overcome the
impedance.

10. Frequency spectrum
 nerve and muscle stimulation cease at 100,000
cycles/second (100 kHz), electrosurgery can be
performed safely at “radio” frequencies above
100 kHz.
 An electrosurgical generator takes 60 cycle
current and increases the frequency to over
200,000 cycles per second.
 At this frequency electrosurgical energy can pass
through the patient with minimal neuromuscular
stimulation and no risk of electrocution.

11. Types of ESU Units
 Monopolar
 Bipolar
(Some ESU units have both
monopolar & bipolar capability)

12. Monopolar ESU
 Electrical energy flows from the
generator (ESU unit), to the active
electrode (cautery pencil).
 The energy then passes through the
patient to the dispersive cautery
pad, thus completing the electrical
circuit.

13. Monopolar ESU
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14. Monopolar Modes
 Cut
 Coag
 Blend- produces cutting effect with
hemostasis

15. cut
 Electrosurgical generators are able to
produce a variety of electrical waveforms.
 As waveforms change, so will the
corresponding tissue effects.
 Using a constant waveform, like “cut,” the
surgeon is able to vaporize or cut tissue.
This waveform produces heat very
rapidly.

16. coagulation
 Using an intermittent waveform, like
“coagulation,” causes the generator
to modify the waveform so that the
duty cycle (on time) is reduced.
 This interrupted waveform will
produce less heat.
 Instead of tissue vaporization, a
coagulum is produced.

17. blend
 A “blended current” is not a mixture of
both cutting and coagulation current but
rather a modification of the duty cycle.
 As you go from Blend 1 to Blend 3 the
duty cycle is progressively reduced.
 A lower duty cycle produces less heat.
Consequently, Blend 1 is able to vaporize
tissue with minimal hemostasis whereas
Blend 3 is less effective at cutting but has
maximum hemostasis.

20. REM System(renewable energy management systems)
 Most ESU units on the market today
have REM technology.
 REM system continually monitors
the heat build-up under the
grounding pad
 If the system detects excess heat
build-up it will shut off the current
flow to prevent patient injury

21. Bipolar Electrosurgery
 Bipolar electrosurgery uses 2-tined
bipolar forceps
 One tine of the forceps serves as the
active electrode, and the other tine
serves as the return electrode
The electrical current is confined
to the tissue between the tines of
The bipolar forceps

22. Bipolar Electrosurgery
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Group LP: All rights reserved

23. Bipolar Surgery
 A grounding pad is not needed for
bipolar-only cases

24. ESU Grounding Pads
 Available in infant & adult sizes
 Infant size: follow grounding pad
manufacturer’s recommendation for
appropriate weight range
 NEVER cut a grounding pad to fit a
patient, always use the appropriate
size pad

25. Function of the Patient
Return Electrode
 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.

26. Dangerous Return Electrode Contact
with Current Concentration
 In the case of reduced contact area, the current
flow is concentrated in a smaller area.
 As the current concentration increases, the
temperature at the return electrode increases.
 If the temperature at the return electrode site
increases enough, a patient burn may result.
 Surface area impedance can be compromised by:
excessive hair, adipose tissue, bony prominences,
fluid invasion, adhesive failure, scar tissue, and
many other variables.

29. Placement of Grounding
Pad
 When considering grounding
placement it is important to know
that electric current travels easily
through muscular & vascular tissue
 Electric current does not travel well
through bone, scar or adipose tissue

30. Best Grounding Pad Site
 Over a well-vascularized muscle
mass
 Avoid placing grounding pad over
bony prominences, hairy sites, scar
tissue,excess adipose tissue

31. Grounding pad site
 Pad site should be free from lotions
or oils
 In some male patients it may be
necessary to remove hair from the
desired pad site using clippers

32. Placing Grounding Pad
 Place grounding pad as close to the
surgical site as possible
 Grounding pad should be placed so
that the entire surface of the pad is
in uniform contact with the pad site
 Avoid any tenting or gaps where
parts of the pad are not in contact
with the patient

33. ESU Safety
 Inspect machine for frayed or
broken wires before use.
 Active electrode wire should be free
of kinks
 Use lowest setting that is effective

34. ESU Safety
 Avoid using the ESU unit as a table-when
doing this setting buttons may be
inadvertently changed or liquid may be
spilled into machine
 If alcohol-containing prep solutions are
used (ex: Duraprep, Prevail) allow
prepped area to dry completely before
using ESU to minimize fire risk

35. ESU Safety
 Recommended practice: keep ESU pencil
in non-conductive holder when not in use-
this prevents accidental activation
 Prep or irrigation solutions should not
pool near the grounding pad
 Don’t allow ESU pedal to stand in pool of
liquid

36. ESU Safety
 No part of the patient should be touching
any grounded metal objects (IV pole,
Mayo stand, metal surfaces of OR bed)
 Electrical current always seeks the path of
least resistance—patient might have an
alternate site burn where their body is in
contact with metal

37. ESU Safety
 When surgeon requests that the
ESU setting be changed, audibly
repeat new setting
 Do not turn ESU activation sound
completely off—sound also alerts
surgical team to accidental
activation of ESU

38. ESU Safety
 If it is necessary to change patient
position intraoperatively, always check
grounding pad site after patient is re-
positioned
 If ESU pencil falls below the level of the
sterile field, disconnect it from the
generator to prevent accidental activation

39. ESU Safety
 If there is any suspicion of patient
injury related to the use of an ESU
unit:
 Immediately remove generator from
service, and send to biomed along with
the grounding pad & used active
electrode

40. Surgical Smoke
 NIOSH (the National Institute of
Occupational Safety and Health) and the
CDC (Center for Disease Control) have
also studied electrosurgical smoke at
length. They state:
“Research studies have confirmed that
this smoke plume can contain toxic gases
and vapors such as benzene, hydrogen
cyanide, and formaldehyde, bioaerosols,
dead and live cellular material (including
blood fragments), and viruses.”

41. Smoke evacuation device

42. Troubleshooting
If surgeon makes repeated requests to increase
ESU power or complains that the “Bovie isn’t
working”:
 Check dispersive pad contact
 Check all connections
 No resolution after taking above steps- change
out ESU pad, pencil and/or machine

43. Special Considerations:
Patients with--
 Implanted pacemaker
 Implanted automatic defibrillator
 Cochlear Implant
 Implanted Bone Growth Stimulator
 Body Jewelry
 Offender monitoring ankle bracelets
 Orthopedic implants (total hips, etc)

44. Metal Implants
(Orthopedic implants, etc)
 Metal is an excellent conductor of
electrical current
 Any metal between the surgical site and
the grounding pad can attract the
electrical current, and cause alternate
site burns

45. Pacemakers
 Bipolar electrosurgery is recommended in
patients with implanted pacemakers who
must undergo surgery
 If monopolar surgery is required,
place the grounding pad on a site where
current will be directed away from the
heart & pacemaker generator

46. Implanted Defibrillators
 Implanted defibrillators should be
deactivated before the surgical
procedure, and reactivated
immediately after the procedure
 After defibrillator is deactivated
the ESU can be safely used for the
procedure

47. Cochlear Implants
 Monopolar electrosurgical instruments
should not be used on the head or
neck of patients who have a cochlear
implant- damage to the implant or
surrounding tissue can occur
 Bipolar ESU may be used, depending
on type of implant electrodes- contact
manufacturer for info

48. Argon-Enhanced
Electrosurgery
 Also known as “Argon Beam
Coagulator”
 Combines argon gas with electrical
energy to increase the effectiveness of
the electrosurgical current
 Argon gas acts as a pathway to carry
the electrical current to the target
tissue- coagulates tissue without direct
contact

49. References
 Conmed Corporation Web site:
http://www.conmed.com/
 Rothrock (2007) Alexander’s Care of the Patient
in Surgery
 Valleylab Web Site:
http://www.valleylab.com/