Patient Monitor User Manual Monitoring SpO
2
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to On in SpO
2
Setup menu to lock the SpO
2
alarm status until the NIBP measurement ends. If
NIBP Simul is set to Off, low perfusion caused by NIBP measurement may lead to inaccurate
SpO
2
readings and therefore cause false physiological alarms.
10.9 Setting Pitch Tone
If tone modulation is on, the PR sound lowers when the SpO
2
level drops. In the SpO
2
Setup
menu, select pitch tone to toggle between On and Off.
10.10 Setting Sensitivity
The different sensitivity indicates different refresh frequency. High indicates the refresh
frequency of SpO
2
value is the most frequent. To change the sensitivity, please follow the steps:
1 Select the SpO
2
Setup menu;
2 Select Sensitivity on the interface and select the desired sensitivity from the popup list.
10.11 SatSeconds Alarm Management*
* Only applicable to the Nellcor SpO
2
module.
* Not applicable to MFM-CMS.
10.11.1 Describing SatSeconds
With traditional alarm management, upper and lower alarm limits are set for monitoring oxygen
saturation. During monitoring, as soon as an alarm limit is violated by as little as one percentage
point, an alarm is immediately triggered. When the SpO
2
level fluctuates near an alarm limit, the
alarm is triggered each time the limit is violated. Such frequent alarms can be distracting.
With the SatSeconds technique, upper and lower SpO
2
alarm limits are set in the same way as
traditional alarm management. However, you can also set a SatSeconds limit that allows
monitoring of SpO
2
below the selected lower alarm limit and above the selected upper alarm limit
for a period of time before an alarm is triggered.
The method of calculation is as follows:
The number of percentage points that the SpO
2
falls outside the alarm limit is multiplied by the
number of seconds that the SpO
2
level remains outside that limit. This can be stated as an
equation:
Points × Seconds = SatSeconds
Where:
Points = SpO
2
percentage points outside of the limit
Seconds = number of seconds that SpO
2
remains at that point outside of the limit
The alarm response time, assuming a SatSeconds limit set at 50 and a lower alarm limit set at 90,
is described and illustrated below.
In this example, the SpO
2
level drops to 88 (2 points below the limit) and remains there for a
period of 2 seconds (2 points × 2 seconds = 4 SatSeconds). The SpO
2
then drops to 86 for 3