Covidien Nellcor GR101704, Service Manual

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System Features
Service Manual 3-13
When the indicator reaches capacity, indicating the SPD limit has been
reached, an audible alarm sounds and an alarm warning flashes. The default
setting of one (1) is the most sensitive to desaturation patterns and results in
more frequent alarms. For less frequent alarms, use a less sensitive setting of
two (2) or three (3).

Note:
Unrecognized repetitive reductions in airflow through the upper airway occur in some
clinically significant scenarios. Patients exhibiting sleep apnea symptoms were used in
studies to validate the SPD™ Alert parameter. The presence of repetitive reductions
in airflow was scored using a standard diagnostic polysomnogram. Study results
indicate SPD is a sensitive marker in detecting repetitive reductions in airflow.
3.7.4
Pulse Rate Delay Alarm Management Parameter
The monitoring system also monitors pulse rate by determining the number of
pleth waves over unit time. With traditional alarm management, upper and
lower alarm limits are set for monitoring pulse rate. When pulse rates fluctuate
near an alarm limit, alarms trigger with each violation. Pulse Rate Delay allows
a period of threshold violation before the pulse rate alarm sounds. Thus, it dis-
tinguishes clinically significant events from minor and brief pulse rate limit vio-
lations that result in nuisance alarms.
To use Pulse Rate Delay, set the traditional alarm management upper and
lower pulse rate alarm limits. Then, set Pulse Rate Delay. The Pulse Rate Delay
limit controls the time the pulse rate level crosses either limit before an audible
alarm sounds.