User Manual

ARRHYTHMIA ANALYSIS
54 PatientNet Operator’s Manual, v1.04, 10001001-00X, Draft
All information contained herein is subject to the rights and restrictions on the title page.
Computerized Arrhythmia Monitoring
Computerized arrhythmia monitoring was never intended to replace the human interface as the
mathematical brain of the computer does not think like ours. It does one thing better than us
however, and that is to provide continuous surveillance of all monitored patients simulta-
neously without fatigue or distractions. The networked monitoring system has a series of
alarm messages and tones to alert clinicians when a change in the patient’s rhythm or other
physiologic parameter being monitored falls outside of the set alarm limits. Arrhythmia data
may trigger an alarm at the time of the event, record at the time of the event, and store the
alarmed event. The stored arrhythmia data can be maintained in memory for recall. This
arrhythmia history is a valuable tool for patient assessment and treatment. When used appro-
priately, computerized arrhythmia monitoring can be an invaluable tool that:
Provides continuous surveillance of all patients
Alerts caregivers to rhythm changes and arrhythmias
Is not subject to human fatigue or distraction
Records an event when it occurs
Stores arrhythmia information in memory: history and 24 or 72 hour full disclosure
Reviews events in history
Algorithm Operation
The operation of the arrhythmia algorithm is a 6 step process:
1. Data Acquisition
2. Data Transmission
3. QRS Detection
4. Template Creation
5. Template Comparison
6. Multiple Beat Classification
Step 1 - Data Acquisition
The ECG signal is collected by surface electrodes and digitized by the front-end
device, which may be a patient worn transceiver or a bedside monitor. The transceiver
digitizes the data at 200 samples per second per vector. Bedside monitors sample at
varying rates and output this data to the V-Link, V-Link II, or DT-7000/DT-7001
instrument transceivers. The instrument transceivers convert the sampling rate to 200
samples per second prior to transmitting the data.
Pacemaker detection is performed by the front-end device on the analog signal. A flag
is encoded in the digital ECG data stream to indicate where a pacemaker pulse was
detected.