Stryker RF MultiGen 0406-900-000, Instructions For Use Manual

Page: 24 / 57

0406-900-702 Rev-E EN
www.stryker.com 23
To Perform Sensory or Motor Stimulation
NOTES:
• For safety purposes, the stimulation energy output is limited to 20 mA in
the voltage-regulated mode.
• Only one electrode may provide an active stimulation energy output.
• Stimulation energy output consists of biphasic square pulses. The values
displayed on the screen are peak-amplitude values and the width values
for each phase. See
Appendix B - Maximum Frequency and Maximum
Stimulation Width Graphs section.
• If the amplitude value is 0.00 V, stimulation output will not start until the
amplitude value is increased using the amplitude arrow buttons.
• The initial amplitude value will determine the stimulation energy output
when the START button is touched. The initial amplitude value should be
set slightly below the point at which clinical experience shows patient
response may be perceived.
• Adjusting the amplitude value may reduce the time required to reach a
value resulting in a patient response.
• For sensory stimulation, the amplitude value where the desired nerve is
triggered will indicate how close the nerve is to the active electrode tip.
Patient response at a lower amplitude value will indicate closer proximity
to the target nerve.
• For motor stimulation, the amplitude value where the nerves are triggered
will indicate how close the nerves are to the active electrode tip. Patient
response at a lower amplitude value will indicate closer proximity to
the triggered nerves. Patient response at too low a motor stimulation
amplitude value increases the likelihood of damage to a motor nerve.
• If the patient is not responding: (1) reposition the electrode, and (2)
verify the proper selection of frequency and width values.
• If the patient is responding at too low an amplitude value (indicating an
undesired proximity to a motor nerve): (1) reposition the electrode and
(2) verify the proper selection of frequency and width values.
• If using a fixed amplitude value, increasing the width value will pass
more stimulation energy into the patient per pulse. In general, increasing
the width value has the effect of recruiting more nerve fibers within the
electrode's proximity and provoking a stronger response. Conversely, a
reduction in the width value will reduce the patient's response.
1. Ensure the frequency, width, initial amplitude, and amplitude step
rate values have been set as required. See To EDIT Sensory or Motor
Stimulation Settings section.
2. If performing a parallel bipolar procedure, touch the PARALLEL button
(see figure 16)
.
3. Touch the START button to apply stimulation energy using the setting
values displayed in the procedure tab area. The active electrode
identifier number will flash and an audible beep will sound to indicate
the stimulation energy is applied (see figure 17).
4. Touch the FAST or SLOW amplitude arrow buttons to adjust the
amplitude value of the stimulation output.
5. Touch the STOP button to remove stimulation energy output.
EDIT EDIT
4
PARALLEL
3
PARALLEL
AMPLITUDE
1.50
v
IMPEDANCE
240
Ω
AMPLITUDE
0.00
v
IMPEDANCE
280
Ω
AMPLITUDE
0.00
v
IMPEDANCE
305
Ω
3 4
STOP
AMPLITUDE
1.50
v
FREQUENCY
50.0
Hz
WIDTH
1.00
ms
PLACEMENT
L3 RIGHT
SENSORY STIM
EDIT EDIT EDIT
260
Ω
1.30
v
IMPEDANCE
AMPLITUDE
275
Ω
0.00
v
IMPEDANCE
AMPLITUDE
300
Ω
0.00
v
IMPEDANCE
AMPLITUDE
290
Ω
0.00
v
IMPEDANCE
AMPLITUDE
1 2 3 4
PARALLEL PARALLEL
STOP
AMPLITUDE
1.30
v
FREQUENCY
50.0
Hz
WIDTH
1.00
ms
PLACEMENT
L3 LEFT
SENSORY STIM
Figure 16 Typical Parallel Bipolar Stimulation Screen - ACTIVE Figure 17 Typical Stimulation Screen - ACTIVE
A Merged Procedure Tabs
Indicates two electrodes (1,2) or (3,4) are combined to operate in a
parallel bipolar mode.
B IMPEDANCE Procedure Tab Value
• This value, displayed in ohms [0-2000 Ω], is continuously
monitored and represents tissue impedance measured by the
electrode(s).
• In stimulation screens, the measurement of tissue impedance is
provided to distinguish between tissue types. Because different
tissue types have different conductivity, a distinction can be
made between tissue types, for example, between nerve tissue
and muscle tissue.
• If no electrodes are connected, the IMPEDANCE tab value will
display “- - -.” If an electrode is connected to any port, but the
value exceeds its limit, the value displayed will be “HIGH” for all
tabs.
• Stimulation cannot be conducted if impedance is outside the
range of 35 to 1800 Ω impedance.
C AMPLITUDE Procedure Tab Value
This value, displayed in volts, represents the amplitude of the
applied stimulation energy.
D AMPLITUDE FAST/SLOW Arrow Button(s)/Window
Once the START button is touched, the amplitude value may
be adjusted by touching the up and down arrows to increase or
decrease the value, respectively. A FAST arrow (double arrow) will
allow 0.1 value changes. A SLOW arrow (single arrow) will allow
0.01 value changes. To make rapid changes, touch and hold the
desired button. The selected value is displayed in the window.
A
B
C
D