Operator's Manual

6.1 Electrocardiography (ECG)
Tempus Pro User/Operator Manual - 41-2001EN-00 – Page 67
 Per EC13, 4.1.4.1, heart rate is accurately indicated in the presence of effective pacemaker single
pulses without overshoot, having width of up to 2 ms and amplitude up to 700 mV, and such pulses
alone do not cause heart rate detection. In the case of ineffectively paced QRS, erratic readings may
result for single pulses above 2 mV. Overshoot is specified according to EC13 4.1.4.1 Method B.
 Per EC13 4.2.9.12, the muscle filter will make pacemaker pulses appear smaller than 2mm. Switch
muscle filters off (Diagnostic filter setting) to see pacemaker pulses more clearly.
 Measurements of the ECG waveform should be normalized against the scale provided. The scale
presents 1 mV as 8 mm with a gain setting of 10mm/mV.
 Note that in the 4 waveform view the channel height of the ECG is 24 mm and thus permits a maximum
input signal of ±2.2 mV when using a gain of 5 mm/mV. In the large ECG view a maximum input signal
of ±5 mV is achieved using a gain of 5 mm/mV. Large ECG view is described in “9.2 Display options”.
 Compliance with EC12 clause 4.2.9.8 b) (and relevant clause of IEC60601-2-25:2011) requirements for
frequency response are achieved only with the muscle filters switched off (i.e. using the Diagnostic filter
setting).
 For leads off detection, the ECG applies a 1 kHz triangular wave of approximately 6 mV p-p between the
R/RL and L/LL electrodes.
 The slew rate of the ECG as per AAMI EC13 4.1.4.3 is 3.7 V/s (all filters off).
ECG recording specifications
The following disclosures are made in accordance with the requirements of AAMI EC11 and IEC60601-2-25:
 Frequency and impulse response has been evaluated according to methods A, B and C of EC11:1991
3.2.7.2/4.2.7.2. All EC11 tests have been performed using SCP files generated by the i2i software as an
acquisition system. Compliance requires that all optional filters be switched off.
 ECG data in this system are contained in computer files, using a proprietary format based on the SCP-
ECG standard. The ECG data are digitized using a sample rate of 500sps and a resolution of
2995nV/bit with 12 bit (4096 level) dynamic range.
 Automated measurements of amplitude and duration of QRS complexes generated from the ECG
recording are only valid for adult patients. For younger patients the values should be measured using
the electronic calipers within i2i.
 Per clause 201.12.1.101.3 automated measurements of the S segment duration of CAL waveforms are
±15 ms. The automated value can be confirmed using the electronic calipers within i2i
 Per clause 201.12.4.107.3 The skew rate is 0
 Automated measurements are only able to distinguish T-waves of amplitudes greater than >50 µV