Data Critical Corporation 02DT-7000 User Manual
TROUBLESHOOTING
210
PatientNet Operator’s Manual, v1.04, 10001001-00X, Draft
All information contained herein is subject to the rights and restrictions on the title page.
Example 4 - Excessive Artifact or Poor Signal Quality
Problem
Older analog systems made the differentiation between electrical and physical inter-
ference (artifact), and poor signal strength or antenna interference, difficult because
they both showed up as artifact on the ECG signal. With newer digital systems, trou-
bleshooting the causes of interference is much easier. Most interferences related to the
antenna system will show up as gaps (drop outs) in the waveform.
ference (artifact), and poor signal strength or antenna interference, difficult because
they both showed up as artifact on the ECG signal. With newer digital systems, trou-
bleshooting the causes of interference is much easier. Most interferences related to the
antenna system will show up as gaps (drop outs) in the waveform.
Artifact caused by 50-60 cycle interference or muscle/motion artifact will appear on
the ECG waveform as artifact.
the ECG waveform as artifact.
Several causes of artifact will be considered (some are physiologic and some are non-
physiologic).
physiologic).
1. 50-60 Cycle Interference
This shows up in the signal as a wide fuzzy baseline that is fairly consistent in size.
The source of this type of interference is from the electrical wiring in the hospital or
other equipment in the area that uses an electrical source. Signals are more prone to
this type of noise if equipment or wall outlets are not properly grounded. Poor skin
preparation and electrode contact, as well as broken lead wires, can also leave the sys-
tem “open” to detecting this type of extraneous noise.
The source of this type of interference is from the electrical wiring in the hospital or
other equipment in the area that uses an electrical source. Signals are more prone to
this type of noise if equipment or wall outlets are not properly grounded. Poor skin
preparation and electrode contact, as well as broken lead wires, can also leave the sys-
tem “open” to detecting this type of extraneous noise.
Fig. 96. Example 4 - 50-60 Mz Cycle Interference