maxium® smart C Electrosurgery Unit with maxium® smart Beam
Revision 1
19
The risk of burns is particularly high where high voltage monopolar currents are used, and in particular with
cutting currents and sparking coagulation currents.
Especially when using monopolar HF currents during endoscopic operations, consider that due to the
capacitive connection between an electrosurgical instrument and other electrically conductive components
(trocar, instrument shafts, ...) used in endoscopy, working current can be present and can cause tissue
burns when tissue comes into contact with such parts.
5.1.3
Leakage currents to other medical devices
A special form of leakage currents are the
leakage currents to other medical devices
also connected to the patient. Although
these units are not integrated into the
circuit of the electrosurgery unit, a small
portion of the HF current flows as
leakage current through the patient ports
of these devices. If the connections
(leads) have particularly small surfaces
and permit larger currents, burns at the
contact sites may result.
Basically, not even a direct electrical connection to the patient is necessary. Even local proximity to the
ground is sufficient (ground capacitance).
The risk of burns is particularly high where high voltage monopolar currents are used, and in particular with
cutting currents and sparking coagulation currents. With the bipolar currents of the maxium®, however, it is
low.
5.1.4
Measures against risks from stray currents
In order to prevent formation of shunts for HF current or concentrated leakage current paths, it is
mandatory to comply with the following instructions when placing the patient on the operating table:
•
Place the patient to be isolated from grounded metal parts. Particular care is required to ensure that
the patient’s limbs do not touch any metal structures either.
•
Ensure the required high-frequency insulation against the operating table by a sufficient number of
layers (insulating blankets). Since during the operation moisture, perspiration, etc. are to be expected,
a waterproof foil must be used to prevent wetting of these layers which serve as high-frequency
insulation.
•
Fluid accumulation under the patient must be avoided under all circumstances. Use further dry cloth
layers where appropriate.
•
Keep areas with stronger perspiration, extremities touching the trunk or skin-on-skin contact apart
from each other and dry (arm-trunk, leg-leg, breasts).
•
Place the neutral electrode as close as possible to the operation field. For surgery on the trunk, the
upper arms and upper legs are good application positions.
•
The above requirements for insulation must also be fulfilled if the patient is repositioned during the
operation.
