Bionet BM5VET, Operation Manual

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BM5Vet Pro User’s Manual
ECG Signal Processing and Display
The monitor displays QRS Complex for an amplitude of 0.4 to 5.0 mV (0.2 -5.0 mV for scale
settings below 0.5 mV / cm) and a QRS width of 70 to 120 ms for large animals (also for small
animals with 40 to 100 ms). The heart rate is calculated from 15 to 300 times per minute using
the last 10 seconds of the R-R interval and the two longest intervals and the two shortest
intervals at the R-R interval. The remaining interval is averaged, and the current heart rate is
displayed in the HR parameter box of the main screen as a result.
If arrhythmia monitoring is possible, the HR parameter box will change accordingly. If you select
Basic, you can display three basic arrhythmias called ASYS, VFIB, and VTAC. If Full is selected, a
separate ARR parameter box will be displayed next to the HR parameter box (for details on
selecting the arrhythmia mode, refer to the Arrhythmia Setting chapter).
When the ECG signal is 80 BPM, the interval of the T wave is 180ms, and the QT interval is 350ms.
ST Signal Processing and Display
ST segment deviation is defined as the movement above or below the equipotential level (mm).
The difference measurement compares the isoelectric point with the ST measurement point. The
isoelectric point defines a zero volt point (no electrical activity, 0 mm) with a base position on the
horizontal axis (in hours) of 28ms before QRS complex generation. In the ST segment, the ST
point occurs between the QRS offset (J point) and the T-wave. The default position is 80ms after
the QRS offset. The following figure shows a typical QRS complex.
The ST analysis method examines ECG signals classified
as “normal” beats on up to seven selected
ECG electrodes. The monitor measures the ST level of the normal bit ECG signal and displays the
deviation from the average ST level value. If ST monitoring is active, the trend of the ST level can
be reviewed in the trend display window