Patient Monitor User Manual Monitoring ECG
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9.3.2 Changing the ECG Filter Settings
The ECG filter setting defines how ECG waves are smoothed. An abbreviation indicating the
filter type is shown underneath the lead label on the monitor display. Filter settings do not affect
ST measurement.
To change the filter setting, in the
ECG Setup
menu, select
Filter
and then select the appropriate
setting.
–
Monitor
: Use this mode under normal measurement conditions.
–
Surgery
: The filter reduces interference to the signal. It should be used if the signal is
distorted by high frequency or low frequency interference. High frequency interference usually
results in large amplitude spikes making the ECG signal look irregular. Low frequency
interference usually leads to a wandering or rough baseline. In the operating room, the Filter
reduces artifacts and interference from electro-surgical units. Under normal measurement
conditions, selecting
Surgery
may suppress the QRS complexes too much and thus interfere with
the clinical evaluation of the ECG displayed on the monitor.
–
Diagnosis
: Use when undistorted quality is required and its own characteristics can be
maintained. The waveform filtered by the bandwidth of 0.05 Hz~150 Hz is displayed so that the
actual changes such as R-wave notching or discrete elevation or depression of the ST segments
are visible.
–
Enhanced
: It should be used if the signal is distorted by strong interference from high
frequency or low frequency. If there is still obviously interference in the signals when select
surgery filter mode, it is recommended to choose the enhanced mode. In this mode, QRS wave
rhythm information is emphasized, its shape information cannot be considered as diagnostic
criteria. Under normal measurement conditions, the selection of this mode may inhibit QRS wave
group and interfere ECG analysis.
–
Diagnosis 1
: To meet the filtering requirements of ST analysis, it is used when ST analysis is
turned on or when ST analysis results are concerned.
–
Customized
: User can set
High-pass Filter
and
Low-pass Filter
as needed. Cutoff frequency
of
High-pass
can be selected as:
0.01 Hz
,
0.05 Hz
,
0.15 Hz
,
0.25 Hz
,
0.32 Hz
,
0.5 Hz
and
0.67
Hz
.
Cutoff frequency of
Low-pass Filter
can be selected as:
25 Hz
,
35 Hz
,
45 Hz
,
75 Hz
,
100
Hz
, and
150 Hz
. After
High-pass filter
and
Low-pass Filter
are set, the bandwidth range of high
– pass bandwidth to low - pass bandwidth can be formed.
9.4 Selecting Calculation Lead
To set the calculation lead, select
ECG Setup
>
Calc. Lead
, or on the
Normal
display interface,
click on the calculation lead waveform area, select
Calc. Lead
from the popup interface to make
the appropriate setting. For 3 Electrodes, II, I, and III are selectable; For 5 Electrodes, II, I, III,
aVR, aVL, aVF, and V are selectable; For 6 Electrodes, II, I, III, aVR, aVL, aVF and leads
corresponding to Va and Vb are selectable; For 10 Electrodes, II, I, III, aVR, aVL, aVF, V1, V2,
V3, V4, V5, and V6 are selectable. Normal QRS complex should be:
The normal QRS should be either completely above or below the baseline and it should not
be biphasic. For paced patients, the QRS complexes should be at least twice the height of
