Physio-Control LIFEPAK 15 - Manual (Page 66)

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LIFEPAK 15 Monitor/Defibrillator Operating Instructions
Acquiring a 12-Lead ECG
Note: The LIFEPAK 15 monitor/defibrillator acquires ECG data and performs the interpretive
analysis based on the full frequency of 0.05–150 Hz. The 0.05–40 Hz bandwidth affects only the
printed appearance of the ECG data.
The 12-lead ECG printed in the 0.05–40 Hz setting can be used to diagnose acute myocardial
ischemia and ST-segment elevation myocardial infarction (STEMI). This is because the low
frequency limit of 0.05 Hz is not changed from the standard diagnostic setting of 0.05–150 Hz.
The 0.05 Hz frequency provides accurate representation of low frequency signals, that is, the P, ST
segment, and T waves. The presence or absence of ST segment changes indicative of myocardial
ischemia or infarction will be accurately reproduced. In addition, the criteria for visual analysis and
interpretation of cardiac rhythm and PR, QRS, and QT intervals are preserved, as is true with
hospital cardiac monitors that have an upper frequency limit of 40 Hz.
However, in some adult patients, the amplitude (that is, voltage) of the QRS may be reduced when
12-lead ECGs are printed at the upper limit of 40 Hz rather than at 150 Hz. Therefore, certain
diagnoses, which depend on R wave amplitude (for example, ventricular hypertrophy), should not
be made using this setting. In the pediatric patient, this effect on R wave amplitude is particularly
noticeable because QRS durations in children are typically quite narrow. Because R wave amplitude
reduction is more likely with pediatric patients, the 12-lead ECG automatically prints at 0.05–150
Hz, overriding the 40 Hz limit, when a patient age of 15 years or younger is entered.