User's Manual

ST/AR Arrhythmia Algorithm
7-4 ST/AR Arrhythmia & ST Segment Monitoring
WarningWarning
During complete heart block or pacemaker failure (to pace or capture), tall
P-waves (greater than 1/5 of the average R-wave height) can be erroneously
counted by the arrhythmia algorithm, resulting in missed detection of
cardiac arrest.
WarningWarning
For paced patients who exhibit only intrinsic rhythm, the monitor can
erroneously count pace pulses as QRS complexes when the algorithm first
encounters them, resulting in missed detection of cardiac arrest. The risk of
missing cardiac arrest can be reduced by monitoring these patients with the
low heart rate limit at or slightly above the basic/demand pacemaker rate.
A low heart rate alarm alarms you when the patient begins pacing. Proper
detection and classification of the paced rhythm can then be determined.
WarningWarning
When an external pacemaker is being used on a patient, arrhythmia
monitoring is severely compromised due to the high energy level in the
pacer pulse. This can result in the arrhythmia algorithm’s failure to detect
pacemaker non-capture or asystole.
WarningWarning
It is possible that pacemaker pulses will not be detected when the ECG
analog output of a defibrillator is plugged into a bedside monitor. This can
result in the arrhythmia algorithm’s failure to detect pacemaker non-
capture or asystole.
ST/AR
Arrhythmia
Analysis
For information on arrhythmia detection, refer to the following documentation:
• ST/AR Algorithm - Arrhythmia Monitoring Application Note,
#452298193051
• IntelliVue Information Center Instructions for Use and Online Help