Covidien Nellcor - Figure 10-5. Third Spo 2 Event: Triggers Satseconds Alarm; Third Spo Event

Theory of Operations
88 Operator’s Manual
10.6.3 Third SpO2 Event
Consider the third event. Suppose the SatSeconds alarm limit is still set to 25.
During this event, the patient’s SpO
2 drops to 75%, which is 10% below the
lower alarm threshold of 85%. Since the patient’s saturation does not return
to a value over the lower alarm threshold within 2.5 seconds, an alarm sounds.
At this level of saturation, the event cannot exceed 2.5 seconds without invok-
ing a SatSeconds alarm.
Figure10-5.Third SpO2 Event: Triggers SatSeconds Alarm
10% drop below the lower alarm limit threshold
x2.5 second duration below the lower threshold
25 SatSeconds; results in an alarm