2.  Greek words therma, meaning heat, and dia,
meaning through.
 The therapeutic generation of local heat in
body tissues by high-frequency
electromagnetic currents.
 1000 deg C
 Current 500mA

3. PHYSICAL
Moderate heat directly to pathological
lesions in the deeper tissues of the body
 Shortwave
 Ultrasound
 Microwave – radar waves

4. SURGICAL
 Cauterize blood vessels
 Destroy neoplasms, warts and infected
tissues.

5.  Source of electron flow and voltage
CIRCUIT
1.Generator
2.Active Electrode
3.Patient
4.Patient return Electrode

6.  60Hz - House hold Appliances
 100KHz - Nerve and Muscle Stimulation ceases
 200KHz-3.3MHz Electrosurgery
 550-1550KHz - AM radio
 54-880MHz - Television

7.  BIPOLAR
 MONOPOLAR

9.  Both Active electrode and return electrode
functions performed at site of surgery – 2
tines of forceps
 Tissue grasped is included in electrical
circuit.

11.  Active electrode in surgical site
 Patient return electrode – electrical plate –
attached elsewhere.
 Current flows through patient
 Localised heating at tip of instrument
 Minimal heating on plate as more surface
area

12.  CUTTING – Continuous current
Sinus wave form
more heat
cell water vaporized
 COAGULATION – interrupted pulses of
current square wave form
less heat
dessication &
sealing of vessels
 BLEND - Combination of cutting and
coagulation waveforms to increase the
degree of haemostasis during cutting.

14.  Blend 1 – Blend 2 – Blend 3
 Vapourise Maximum
tissue hemostasis

15.  Waveform
 Power setting
 Size of electrode
 Time
 Manipulation of electrode
 Type of tissue
 Eschar

16.  interfere with pacemaker function
 Superficial burns if use spirit based skin
preparation
 Diathermy burns under indifferent electrode if
plate improperly applied
 Channeling effects if used on viscus with narrow
pedicle (e.g. penis or testis)

19.  circuit is completed not by the ground but by
the generator
 recognizes the patient return electrode as the
preferred pathway back to the generator
 If the circuit to the patient return electrode is
broken, an isolated generator will deactivate
the system because the current cannot return
to its source.

20.  So protection from alternate site burns but not
from return electrode burns

23.  Choose: Well vascularized muscle mass
 Avoid: Vascular insufficiency
Irregular body contours
Bony prominences

25.  Instant Response Technology
 Measures and provides instant response to
changes in tissue impedance/resistance at the
electrode contact site
 consistent tissue effect as demonstrated by a
high Power Efficiency Rating (PER)
 Controls maximum output voltage

26.  Vessel Sealing Technology
 combines pressure and energy to create a seal.
The seals have been proven to withstand more
than three times normal systolic blood pressure.

27.  Direct coupling: active electrode is near
another metal instrument :gets energized
 Insulation Failure: coagulation waveform -
high in voltage. This voltage or “push”
can spark through compromised
insulation. Can “blow holes” in weak
insulation.
So use Cutting current in direct contact
with the tissue for coagulation

28.  Inspect insulation carefully
 Use lowest possible power setting
 Use a low voltage waveform (cut)
 Use brief intermittent activation vs. prolonged
activation
 Do not activate in open circuit
 Do not activate in close proximity or direct
contact with another instrument

29.  Use bipolar electrosurgery when
appropriate
 Select an all metal cannula system as
the safest choice.
 Utilize available technology, such as a
tissue response generator or an active
electrode monitoring system, to
eliminate concerns about insulation
failure and capacitive coupling.

30. Teflon® (PTFE) Coating and
Elastomeric Silicone Coating
Elastomeric silicone
coated
electrodes

31.  Inert
 Noncombustible
 Easily ionized by RF energy
 Creates bridge between electrode and
tissue
 Heavier than air
 Displaces nitrogen and oxygen

32.  Decreased smoke, odor
 Decreased blood loss, rebleeding
 Decreased tissue damage
 Flexible eschar

33.  created when tissue is heated and cellular
fluid is vaporized by the thermal action of an
energy source.
 Viral DNA, bacteria, carcinogens, and irritants
are known to be present

34.  “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.”

35. attached directly to a standard electrosurgical pencil

36.  “The ESU should not be used in the presence
of flammable agents
 Avoid oxygen enriched environments
 Use of a nonconductive holster
 Use manufacturer approved insulated tips

37.  Cords not be bundled together
 Cords not be wrapped around metal
instruments