Welch Allyn Acuity Directions For Use Manual page 165

Directions for use
Arrhythmia Analysis and ST Analysis
Table 17. Troubleshooting arrhythmia and ST-segment analyses
Problem
Arrhythmia analysis
or ST analysis does
not seem to be
optimal.
Explanation
WARNING Ensure these things to minimize false HR, Arrhythmia Analysis and ST
Analysis alarms, and to achieve optimal event detection and analysis:
•ECG cable, lead wires and electrodes are undamaged.
•Patient's skin is properly prepared.
•Electrodes are placed using standard good practices.
•5-wire ECG cable is used. A 3-wire cable limits arrhythmia and ST-segment analyses to
a single lead, and ST analysis is disabled when a lead failure occurs.
•LL electrode is connected. Otherwise, only one ECG lead is available and arrhythmia
and ST-segment analyses are effected.
•Patient monitor and Virtual Monitor display these things:
-HR numeric and ECG waveform
-Non-noisy signal. If signal is noisy, reduce patient movement and increase distance
from other electrical devices.
-Correct patient mode for the patient
•Virtual Monitor ECG 1 and ECG 2 display these things:
-ECG waveform
-Waveform amplitude at least 160 µV, peak-to-peak
-QRS complex amplitude at least twice the P or T wave amplitude
WARNING If your system includes arrhythmia analysis, and if you connect, change or
move an electrode, ensure that a RELEARN alert occurs at the patient monitor and the
virtual monitor.
Moving or changing an electrode can change the beat morphology. If the system does
not learn the new morphology, it might not alarm or it might cause false alarms. The
relearn process establishes the new morphology as the normal ECG rhythm for
arrhythmia and ST-segment analyses.
•If a RELEARN alert occurs after changing or moving an electrode, carefully evaluate
the new ECG rhythm and the current ST segment for all active leads to make sure that
the Acuity System has learned an appropriate rhythm. For evaluation instructions, see
"Respond to a RELEARN alert" on page
•If a RELEARN alert does not occur after changing or moving an electrode, initiate a
relearn event. For instructions, see
arrhythmia and ST-segment analyses"
WARNING If you turn on Single ECG in response to false lethal arrhythmia alarming (for
example, due to bundle branch block or irregular rate), arrhythmia analysis is limited to
one lead. Typically, 3-lead analysis (via a 5-wire cable) is optimal.
WARNING In some clinical environments and due to some physiologic differences
among patients, the Acuity System might not alarm for occurrences of ventricular
tachycardia, ventricular fibrillation, or asystole. For instance, asystole is defined as an
absence of any detected beat for four or more seconds. Patient pathologies where
indications of electrical activity continue to exist without adequate cardiac function
might not be recognized as asystole.
WARNING Turning off alarming for arrhythmia types and ST Analysis disables both
audio and visual alarm indicators. Although alarming for lethal arrhythmias cannot be
turned off, patients susceptible to arrhythmias must be kept under close physical
surveillance if their alarming has been turned off for any arrhythmia types.
WARNING If a patient's ST analysis is turned off, the patient's ECG is not analyzed for
ST-segment deviations. ST alerts or alarms are not generated, and ST information is not
stored as graphical trends. The Acuity System can be configured to set ST analysis to Off
as a default setting. For further information, see your system administrator.
Chapter 10 Troubleshooting and maintenance
91.
"To initiate relearn of a patient's ECG rhythm for
on page 65.
161