Product Manual

Patient Monitor User Manual Monitoring ECG
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9.10.4 Selecting QT Analysis Lead
There are two modes for selection:
All lead: Use all available leads (expect pressurized the limb lead) to produce an overall QT
measurement, user can select ALL through ECG Setup > QT Analysis > Analysis Lead.
Single lead: QT measurements were performed using all single leads available in the lead (except
the pressurized limb lead). User selects any lead in Analysis Lead menu to enter into single lead
mode.
9.10.5 Selecting Calculation Formula
The monitor uses Bazett formula to correct QT values by default. There are four alternative
formulas: Bazett, Fridericia, Framingham and Hodges.
Hodges:
60)(HR1.75QTQTc 
Bazett:
2
1
60
HR
QTQTc









Fridericia:
3
1
60
HR
QTQTc









Framingham:
)
HR
60
(1154QTQTc 
9.10.6 Setting QT Baseline
To quantitatively express the QTc values change, the user can set a QTc baseline, the baseline is
used for calculating ΔQTc value. The user can set the baseline through ECG Setup > QT
Analysis > Save Baseline, and the monitor displays The Baseline is saved at: (Time). If no
baseline has been set, the first five minute QTc value after the QT measurement begins will be
automatically set as the baseline. If a new baseline is set, the previous baseline is discarded.
Because ΔQTc alarm is based on the difference of the baseline with the current values,
inappropriate baseline settings may lead that no ΔQTc alarm is generated.
NOTE:
The QT baseline will be cleared in following situations:
1) Turning off the monitor;
2) Changing the electrode type;
3) Changing the calculation lead in 3 electrodes;
4) Changing the patient type;
5) Admitting new patients;
6) Enters or exits Demo mode.
If QT analysis is needed, please reset the baseline.