User's Manual

Ultraview Care Network
8-20
Noise Detection
Upon detection of noise, a NOISY SIGNAL message is displayed in the ECG
waveform zone. If both the 1st and 2nd leads are noisy, the module suspends
processing temporarily. If the noise persists for 10-seconds, the system sounds a
tone. When the noise disappears, the message and tone cease.
False Alarms
Careful attention to skin preparation and electrode application, especially during
setup, will reduce false alarms. Should false alarms occur, check for the following:
• There may be excessive noise on the signal (the most common cause of
false alarms). Electrodes misplaced over muscles or a poor lead connection
can cause significant noise when the patient moves.
• Heart rate limits may be set too close to patient's heart rate. Check to see if
this is the case and adjust the limits as necessary.
• The ECG amplitude may have dropped below the R-wave detector threshold
level causing false low rate alarms. Reposition the electrodes to obtain a
QRS amplitude of at least 0.20 mV (adult) and 0.15 mV (neonate).
• QRS frequency components and shape may be unsatisfactory for accurate
beat detection and classification. Make necessary changes in electrodes,
electrode sites or lead selection to restore a good signal.
• In some cases, VFIB may resemble previously classified abnormal beats
which may cause VFIB to be detected as a RUN. If this occurs, use the
waveform display as the primary indication of condition.
• The module may not recognize some beats as morphologically different from
the learned dominant beat. You may be able to improve performance by
changing electrode positions or switching to a lead setting that provides
better differentiation between the dominant and abnormal beats.
!
• If monitoring is interrupted due to overload or saturation of the
input amplifiers, including overload caused by a defibrillator
discharge, the ECG trace is displayed as an out-of-range signal
accompanied by a NOISY SIGNAL or an HR UNAVAILABLE
message, or both. If the overload or saturation condition
persists, the ECG trace is displayed as a flat line signal
accompanied by an ASYSTOLE message.
• If the displayed waveform does not appear noisy, but the
NOISY SIGNAL message persists, check all leads for noise
before calling a qualified service person.