Welch Allyn Atlas Monitor - User Manual - Manual (Page 24)

12
2.2 Monitoring SpO
2
, Pulse Rate and the SpO
2
Waveform
The oximetry and pulse rate measurements are generally taken with the reusable fingerclip sensor
(provided), however a wide variety of SpO
2
sensors are available as accessory items. The oximetry pulse
volume is displayed as a vertical bar graph, called the Plethysmograph, beside the SpO
2
% display on the
right side of the monitor. The SpO
2
pulse tone gives an audible indication of pulse rate and oxygen level.
Pulse - A fingerclip sensor provides the source
of the light transmitted through the patient’s
finger to determine the oximetry and pulse rate
measurements. The green Pulse Rate numbers
may sometimes differ slightly from the Heart
Rate displayed over the ECG waveform, even
though they both measure beats per minute
(bpm). This is normal.
Oxygen level - The oxygen level is displayed in
red numbers as a percentage. The
Plethysmograph vertical bar graph next to the
SpO
2
percentage shows the strength of the
fingerclip sensor signal with each beat. If this
signal is low, it could indicate that the fingerclip
sensor is not placed properly, or that the patient
has poor perfusion. Pigmented skin and nail
polish can also lower the signal.
System Displays – The system will begin
displaying the Plethysmograph signal almost
immediately upon attachment of the fingerclip
sensor to the patient. The SpO
2
level and Pulse
Rate will be displayed within about 5 seconds,
after the system determines that the reading is
stabilized.
Second waveform - The pulse oximetry
waveform can be selected as a second trace. If
this is chosen, the bottom line of the screen
displays the SpO
2
waveform. Select the Second
trace source from the Advanced Configuration
menu.
Pulse tone - A short SpO
2
tone sounds with
every pulse beat.
• The pulse tone timing is based on the ECG
heart rate. If ECG is not used, the pulse tone
timing is based on the SpO
2
measurement.
• The pulse tone pitch is determined by the
oxygen level, increasing in frequency (pitch)
as the percentage of oxygen elevates.
The pulse tone volume can be controlled by a
button on the lower right panel. The button is
below the SpO
2
display, labeled with a speaker
icon and SpO
2
.
Note: The pulse tone volume can be turned
completely off with this button.
Note: If the SpO
2
is inactive, the timing of the
SpO
2
pulse tone is in synchrony with the
ECG heart rate as is normally the case, but
the pitch of the tone is steady, unvarying, and
different from the tone tracking oxygen
content.
Alarms - When the oxygen percentage falls
below the SpO
2
limit, an alarm sounds and the
affected measurement flashes. If the Print On
Alarm configuration is set to Yes, an SpO
2
alarm
will trigger an automatic print. You can silence
the SpO
2
alarm, and all alarms, by pressing the
large blue Silence button at the right side of the
instrument. This will silence all alarms for 60,
90, or 120 seconds, depending on the setting
selected in Advanced Configuration. However,
any measurement still outside the set limits will
flash. When alarms are silenced, they do not
trigger a Print On Alarm.
To suspend the SpO
2
alarm, press the SpO
2
ALARMS Off button so the red LED in the
button lights. A suspended alarm will still flash
if it goes outside the range of the limits, but it
will not sound the audible alarm. When an alarm
is suspended, it will not trigger a Print On
Alarm.