may be done simultaneously or individually. These processes are particularly
applicable for use in the presence of cancerous tissue. Removal of malignant growths
by mechanical (hand) surgery is dangerous because cells may break off, travel to other
parts of the body via the circulatory system, and spread the cancer. However, in
electrosurgery, blood vessels are closed as they are cut, preventing the spread of
cancer in this way.
(b) Another advantage relates to blood loss. Electrosurgery decreases
blood loss. Cauterization is very effective in obtaining hemostasis (arresting the flow of
blood). By setting the unit for cauterization, the surgeon need only touch the instrument
to the hemostat (clamp which controls bleeding) he has placed on a bleeder and the
bleeding is stopped. In mechanical (hand) surgery, each layer of tissue cut requires
many hemostats and many ties. Considerable blood is lost while time is taken to tie
each bleeder.
(2)
The electrosurgerical apparatus has an active electrode and an inactive
electrode.
(a) Current passes into the patient's body through an active electrode,
the operative tip. A tip is small in area, concentrating the current; hence, it generates
considerable heat where the surgeon applies it. The active electrode and its connecting
cord are the only parts of the unit sterilized for the operation. This operative tip used by
the surgeon is heated only while it is being used; either by a switch on the active
electrode handle or by a foot switch, placed near the operating table.
(b) The electrical circuit is completed with the inactive electrode, a
large plate made of CRM. This plate is large so that the energy is spread over a large
surface area, such as the buttocks, dispersing the current and producing only negligible
heat. The inactive electrode is often placed under the patient's buttocks because of the
fleshy, smooth tissue available there which can provide a good contact. The area used
for inactive electrode must be free from scars and excessive hair. Scar tissue is made
up of uneven connective tissue, which does not provide good contact. Hair is not
conductive and must be removed for a good contact. In addition, bony portions of the
body should not be in contact with the inactive electrode because they provide an
uneven current distribution, which may lead to burns. Before the inactive electrode is
positioned, it should be covered with contact paste (electrocardiograph electrode paste).
This paste facilitates passage of electricity. K-Y lubricating jelly should NOT be used
because it is nonelectrolytic and will insulate the electrical contact. This will cause
current to pass through the thin portions of the K-Y jelly, thus concentrating the current
and causing burns to the patient. Disposable plates that conform to the body are also
used.
MD0923
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