User's Manual

Ultraview Care Network
8-12
When using temporary transvenous pacemakers, you may want to check the
pacemaker capture threshold on a regular basis (refer to your hospital protocol for
frequency and procedure). Since the pacemaker flag substituted by the monitor
does not represent the true amplitude of the detected pacemaker pulse, you will
need to temporarily deactivate the Ultraview Care Network pacemaker software to
check the capture threshold. In addition, placing the display in the extended mode
and changing the sweep speed to 50 mm/sec will enhance the resolution and
improve visualization of the pacemaker pulse amplitude. Remember to return to
the monitor mode, reactivate pacemaker detection, and reset desired sweep
speed after checking the capture threshold.
Permanent transvenous pacemakers employing a bipolar lead system are
capable of obtaining capture of the cardiac muscle at a much lower current than
those with unipolar lead systems. For optimal paced rhythm detection, the
pacemaker pulse and QRS complex must be of sufficient voltage. To determine if
the monitor is correctly detecting the pacemaker pulses, verify that the Paced
mode is activated. Each paced beat should have a pacemaker flag superimposed
on the ECG trace at the appropriate point prior to the QRS complex. If flags are
not consistently observed, sequence through the available leads for a better lead,
or reposition electrodes, to optimize pacemaker detection. Check the amplitude of
the QRS complex by inserting a 1 mV calibration pulse in the ECG trace as
described in Checking the ECG Amplitude on page 8-15.
WARNING:
• ECG detection circuitry may continue to count the
pacemaker rate during occurrences of cardiac arrest or
some arrhythmias. Do not rely entirely upon ECG rate
alarms. Keep pacemaker patients under close surveillance.
• During electrosurgical activity, the system may not
accurately detect paced beats due to the electrical
interference.
• The system may insert pacemaker flags into the ECG
signal in response to signals that are not pacemaker
pulses. Therefore, if you use a Spacelabs Medical monitor
to observe pacemaker performance, you must take into
account all possible sources of pacemaker flags.
• Use the pacemaker manufacturer's performance analyzer
as the primary means of evaluating pacemaker operation.
• Operation of some pacemaker programs may suppress the
ECG waveform, preventing QRS detection and rate
counting. This may result in an erroneous asystole alarm.
• Signals resulting from devices such as Automatic
Implantable Cardiac Defibrillators (AICD) may momentarily
blank the ECG trace rather than display an out-of-range
signal. In such cases, it may not be apparent that the AICD
has signaled and the condition of the patient should be
checked. In all instances of AICD signaling, the bedside or
central will redisplay the ECG waveform within 5-seconds.
To check capture threshold:
1 Touch ECG.
2 Touch SETUP.
3 Select PACED NO.
4 Select EXTENDED.
5 Touch SWEEP SPEED.
6 Select 50 mm/sec.
7 Perform capture threshold
verification procedure
according to your protocol.
8 Touch ECG.
9 Touch SETUP.
10 Select PACED YES.
11 Select MONITOR.
12 Touch SWEEP SPEED.
13 Select desired speed.