maxium® smart C Electrosurgery Unit with maxium® smart Beam
Revision 1
23
5.3
Risks from Arcing and Sparking
Under the intended conditions of usage, at the active electrode electric arcs or sparks (arcs of very short
duration) are formed which are capable of igniting combustible material. The plasma beam of the argon
beamer is also capable of this. This risk is considerably increased by the presence of medical oxygen, since
in an oxygen-rich atmosphere combustive reactions are easier to ignite and more violent. Nitrous oxide,
itself non-combustible, may work as a fire accelerant like oxygen.
Flammable substances in the operation area are:
•
Anesthetics
Flammable anesthetics such as ether form explosive mixtures with breathing air even at concentrations
as low as those regularly used.
•
Solvents in cleaning and disinfecting products
They are used before the actual surgery, so that the solvent will have evaporated from the skin.
However, these substances may accumulate in depressions such as the navel or moisten the cover of
the operating table and thus remain present for extended periods of time.
•
Wipes, cotton wool, gauze
Under normal atmosphere, these substances are not easily ignitable by arcs or sparks. However, cotton
and products made of it are prone to adsorb oxygen, significantly increasing their flammability and the
violence of the combustion.
•
Plastic hoses and films
Under a normal atmosphere, these substances are usually self-extinguishing and cannot be ignited by
the arc at the active electrode. Under an oxygen-rich atmosphere, however, they are combustible,
unless made of silicone or Teflon.
•
Endogenous gases
In the gastrointestinal tract, digestion produces gases comprising combustible components (hydrogen,
methane). In case of opening of the gastro-intestinal tract by electrosurgery, inflammation and
deflagration of these gases may result.
•
Pyrolysis and electrolysis gases
During electrosurgical cutting, thermal decomposition of the tissue lead to the formation of small
amounts of pyrolysis gas. In surgery under liquid, there also occurs electrolysis of water due to the high
voltage between active electrode and tissue. During interventions with long activation times such as
TUR, these gases formed at low rates may accumulate to form bubbles. If the active electrode enters
this gas bubble, deflagration may result.
•
Metal parts in the body
In case of metal parts present in the body, such as hip stems, ensure that they are not exposed to
HF currents under any circumstances. HF currents can lead to surface damage (fusing) resulting in a
notching effect that can cause fatigue bending fractures of the metal part, even several years later.
In order to avoid fire and explosion hazards in the use of electrosurgery, the following rules must be
observed:
•
Use no ignitable anesthetics.
•
Accumulations of combustible liquid under the patient, in depressions such as the navel or in body
cavities such as the vagina must be removed before any electrosurgery unit may be used.
