Encision EM3 AEM, Руководство пользователя, Страница: 33 / 48

Principles of Operation
EM3 AEM Monitor User’s Guide 5-3
The AEM instruments incorporate a layered design. AEM instruments are shielded and
monitored to prevent stray electrosurgical burns along the shaft of the instrument caused by
insulation failure or capacitive coupling. The protective shield built into all AEM instruments
provides a neutral return path for capacitively coupled energy and protection from insulation
failure. The shield is continuously monitored during surgery which provides continuous
assurance of the integrity of the instrument.
The AEM Monitor measures the currents flowing in the AEM instruments, detects faults in the
insulation, and monitors the connections of the shield and the return electrode. The
Monopolar Adapter connects the AEM Monitor to an electrosurgical generator. An AEM
instrument and the return electrode connect to the AEM Monitor. When an insulation fault or
connection fault is detected, the AEM Monitor interrupts the circuit to the electrosurgical
generator. In the event of a fault, an alarm sounds and a visual indicator illuminates.
NOTICE
The peak open circuit voltage produced by the electrosurgical generator may be slightly
reduced when it is used with the AEM system. Normally the voltages produced under loaded
conditions are not significantly altered.
Theory of Operation – End Point Monitoring System (Bipolar)
The surgeon may use the Bipolar Current Indicator (a radio-frequency (RF) ammeter) to aid
in determining the end point of bipolar electrosurgical desiccation.
Desiccation is a process whereby heat is dissipated in tissue, and the electrolytic fluid is
driven away. As desiccation takes place the electrical impedance of the tissue and the flow
of current changes. A bar graph displays the current from 0.1A to 1.1A. As the current
increases, the frequency of clicks increases.
Use the Bipolar Current Indicator in conjunction with visual, tactile, temporal, and aural
information observed during surgery. The surgeon must use all the information presented
and interpret it with reference to experience to determine that desiccation is satisfactorily
completed. Thus, it is important not to draw conclusions about the completion of desiccation
from the indications of the Bipolar Current Indicator alone.
AEM Monitor
1) Detection of Insulation Failure
2) Protection against Capacitive
Coupling
Electrosurgical
Generator
AEM Instrument
Return
Electrode
Monopolar
Adapter