Determine Optimum Threshold - ZOLL R Series Operator's Manual

C 8 N
HAPTER ONINVASIVE

6 Determine Optimum Threshold

The ideal pacer current is the lowest value that maintains capture — usually about 10% above
threshold. Typical threshold currents range from 40 to 80 mA. Location of the hands-free
therapy or OneStep therapy electrodes affects the current required to obtain ventricular capture.
Typically the lowest threshold is obtained when the position of the electrodes provides the most
direct current pathway through the heart while avoiding large chest muscles. Lower stimulation
currents produce less skeletal muscle contraction and are better tolerated.
4:1 Mode
OFF
PACER
OUTPUT OUTPUT
Pressing and holding the 4:1 button temporarily withholds pacing stimuli, thereby allowing you
to observe the patient's underlying ECG rhythm and morphology.
When depressed, this button causes pacing stimuli to be delivered at ¼ of the indicated ppm
setting.
Pace Fault
If the unit is attempting to deliver pacing therapy and one of the following conditions occur, the
messages CHECK PADS and POOR PAD CONTACT are alternately displayed on the screen
and an audible alarm sounds:
The OneStep cable is not connected to the device.
•
The cable is defective.
•
Therapy pads are not connected to the OneStep cable.
•
The therapy pads are not making good skin contact.
•
The alarm will continue to sound until proper connections between the patient and pacer are
achieved and the leftmost softkey (Clear Pace Alarm) is pressed.
ECG
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
00:01
Clear
Pace
Alarm
8–6
T P
EMPORARY ACING
4:1
RATE RATE
mA mA ppm ppm
CHECK PADS
PACE
50 mA 70 PPM
www.zoll.com
(O )
PTIONAL
Async
Pacing
On/Off
9650-0912-06 Rev. G