User's Manual

ST Analysis
10-7
As a second example, assume the SINGLE ST alarm is set at 1.00 mm. The initial
ST amplitude for a particular lead is +0.60 mm. Based on the initial reference level
of 0.00 mm, an alarm would activate if the ST level exceeds +1.00 mm. Therefore,
no alarm occurs. Instantaneously, the ST level increases to +1.20 mm. SINGLE
ST alarm occurs and the new reference level for the lead is set to +1.20 mm. The
next ST alarm for that lead, assuming no changes are made in other leads, would
be activated at +2.20 mm.
Selecting Leads for ST Alarms
Touching the ST LEADS key allows you to select which leads are to be used to
generate ST alarms. Leads that are not clinically relevant for a patient can be
disabled to allow tighter limits to be placed on more clinically significant leads.
All highlighted leads will be used to generate ST alarms.
The factory default setting is all leads included.
Displaying Real-Time ST Trends
To facilitate the assessment of short-term changes in ST-segment levels,
measurements for a single lead can be displayed as a real-time trend.
The amplitude scale for the trend display is dynamically adjusted to show the
maximum and minimum values for the selected time scale.
The time scale for the trend display is user-selectable — either 15-minutes or
30-minutes.
Trend data is continuously updated at 3-second intervals.
To select or deselect leads for ST
alarms:
1 Touch ECG.
2 Touch ALARM LIMITS.
3 Touch ST LEADS.
4 Select or deselect leads.
To display a real-time ST trend:
1 Touch ECG.
2 Touch REVIEW.
3 Touch REAL TIME ST TREND.
4 Select ON.
5 Select TREND TIMEBASE of
15- or 30-minutes.