Users Manual Part 1

43
Nerve Integrity Monitor
• Additional Options - toggle the following options on/o that are available only in Thyroid procedures:
— Monitoring study group adapted color scheme (2018) – changes the color conditions for alerts.
— Alarm on best channel – When the user uses the Alarm on Best Channel, the system assigns the status from the individual
trended channel with the highest amplitude as the alarm condition. When the user does not use the Alarm on Best Channel,
the system assigns the status from the individual trended channel with the lowest status as the alarm condition. Alarm on
Best Channel is on by default and cannot be disabled when Single Channel Mode is in use.
Use the advanced alarm settings selections to customize the following alarm settings (Note: These settings may behave dierently if
Alarm on Best Channel is in use):
• Amplitude Only sets the alarm to sound if the EMG response tolerance limit is reached regardless of the latency (default is 50%
less than baseline and lower than 2000µV). You can also set an absolute alarm limit in this area.
• Latency Only sets the alarm to sound if the latency tolerance limit is reached regardless of the amplitude (default is latency value
plus(+) 10%).
• Absolute alarm limit example: If the baseline amplitude is 3000 μV, the amplitude percentage limit is 50% (1500 μV), and
Amplitude Absolute limit is 1000 μV, then a signal of 1400 μV would not cause an alarm because although the signal has
decreased more than 50%, it is still above the absolute limit.
• Absolute Alarm Adjustment. This is an actual EMG voltage response above which the percentage alarm is disabled.
• Amplitude OR Latency sets the alarm to sound if either the EMG amplitude OR the latency limit is reached.
• Amplitude AND Latency only sets the alarm to sound if BOTH the EMG amplitude AND the latency limits are reached.
• The Latency type button is located to the right of the Increase button and toggles between percent (%) and msec.
— Percentage – this is the percentage increase in latency from the baseline latency at which an alarm condition occurs (for
example, if the setting is 10%, then an alarm occurs when the amplitude goes above 110% of baseline - a 10% increase).
— ms – this is the increase in latency (in milliseconds) from the baseline latency at which an alarm condition occurs (for example,
if the setting is 1.5 msec and the baseline latency is 8.0 msec, then an alarm occurs when the latency goes above 9.5 msec).
Audio – understanding what you hear
The NIM Vital system Nerve Monitor produces many dierent sounds throughout the surgical procedure that alert you to various
important information. In addition to EMG sounds, the system uses beeps and voices to provide useful information.
Alarms
The alarms draw attention to any condition which prevents you from properly monitoring the surgical procedure. You should not
ignore any of the audible alarms. You must assume that valid monitoring has stopped and determine immediately why the alarm
sounded.
There are four distinct alarms:
• BEEP alarm. This is a high-pitched repetitive beep. You will hear the alarm under the following circumstances:
— Power on.
— Power o.
— System failure. Stop using the NIM Vital system and contact Medtronic.
• Bleedle alarm. This is a three-note alarm (Blee-Dle Deet) that you cannot disable. You will hear the alarm under the following
circumstances:
— Completion of power up.
— Check electrode. The alarm repeats if there is an electrode issue until you remedy the responsible condition.
• As soon as contact with an electrode is lost after removal including lost contact with Nervassure electrodes.
• The channel shows a lead o message.
• The system mutes the channel until connection is restored.
— Muting. As soon as the Muting Detector senses current ow, the dialog box “ EMG MONITORING IS DISABLED/Muting from
external source” appears and the system becomes mute. After 30 seconds, the bleedle alarm sounds followed by the “Muting”
voice. The bleedle alarm repeats every 30 seconds until you remedy the condition.
— Stimulus tone (warbled).
FCC use only, not for Medical use