Chapter 5: ECG
Operation Manual SurgiVet
®
V3404 Plus
5-1
Chapter 5: ECG
Theory of Operation
Electrical currents influenced by the cardiac impulse flow through the body tissue around the heart. Three or
five leads, placed on the skin on opposite sides of the heart, transmit the electrical potentials to circuitry in the
monitor.
The monitor’s ECG circuitry amplifies, filters, and digitizes (converts analog signals to digital signals) the received
electrical potentials. The digitized signals are used to display the ECG waveform and calculate the ECG heart rate.
ECG Warnings, Cautions, & Notes
WARNING! PACEMAkER PATIENTS. Rate meters may continue to count the pacemaker rate during
occurrences of cardiac arrest or some arrhythmias. Do not rely entirely upon rate meter
alarms. keep pacemaker patients under close surveillance. See this manual for disclosure of
the pacemaker pulse rejection capability of this instrument.
WARNING! PACEMAkER PATIENTS. If PACE DETECT is not turned on when monitoring pacemaker patients
the heart rate readouts derived from the ECG patient connections are likely to display
erroneous high or erratic rates. keep pacemaker patients under close surveillance. For
pacemaker patients it may be advisable to select the SpO
2
parameter as the primary heart
rate source.
WARNING! Connect only three-lead or five-lead ECG lead wires from the patient to the ECG patient cable.
Do not connect any other signal source to the ECG patient cable.
WARNING! False low heart rate indicators or false Asystole calls may result with certain pacemakers
because of electrical overshoots.
WARNING! Reliable monitoring of pacemaker patients can only occur with the pace detect on.
WARNING! The pacemaker spike shape and size is not to be diagnostically interpreted.
WARNING! Monitoring of pacemaker patients can only occur with the PACE DETECT on.
WARNING! keep pacemaker patients under close observation. Rate detection in the software may
continue to count the pacemaker rate during cardiac arrest and/or arrhythmia conditions.
Therefore, do not rely solely on rate detection alarms.
WARNING! Do not use line isolations transformers with this monitor. Line isolation monitor transients
may resemble actual cardiac waveforms and thus inhibit heart rate alarms.
WARNING! Electrodes of dissimilar metals should not be used.
NOTE: Follow institutional standards when applying ECG electrodes. Silver/Silver Chloride disposable
electrodes are strongly recommended to avoid polarization effects that result in large input offset
potentials. Use of “squeeze bulb” type electrodes is not recommended.
NOTE: Use only standard AAMI three-lead or five lead ECG cables.
NOTE: Line isolation monitor transients may resemble actual cardiac waveforms and thus inhibit heart
rate alarms.
