A schematic of the Medtronic 5388 is shown below (Figure A1); a few selected dials and buttons will be explained within this appendix. The Medtronic manual should be used for a comprehensive review of the device; the manual was used to construct this brief review in the event that the Medtronic manual would be unavailable in the deployed setting.
POWER ON/OFF: The ON button is marked in green (number 11, Figure A1) and the OFF button is number 12 above. Press the ON key once. The upper screen lights up and the pacers initiates a self-test. Once a successful self-test is completed the following occurs: A sufficiently charged battery will allow the device to begin sensing and pacing in both the atrium and ventricle at the following nominal parameter values. Press the “OFF” button twice within 5 seconds. After the first press, a message appears in the lower screen telling the user to press OFF a second time to turn the device off.
EMERGENCY/ASYNCHRONOUS BUTTON: Press this key (number 13, Fig A1) once to select high-output, dual- chamber asynchronous (DOO) pacing at any time, whether the device is off or locked. Use caution to avoid accidentally activating the Emergency key. This button should be used if electromagnetic interference causes over sensing inhibiting the pacemaker from firing causing hemodynamic instability. The device will pace at the following values:
Adjusting the rate, A output, and V output in emergency mode: These parameters can be adjusted using the three upper dials (numbers 4, 5, and 6) on the right side of device marked in yellow in Figure A1; these dials will be detailed below. To return the device to demand or synchronous pacing:
The device will begin synchronous pacing with the following values:
ADJUSTING RATE, A OUTPUT, AND V OUTPUT: the parameter settings are displayed numerically and graphically. The dials for adjustment are the numbers 4, 5, and 6 respectively (marked in yellow, Figure A1). The line next to each dial shows the range available for each parameter. The liner graph appears above the corresponding numerical value.
Rate dial (number 4 in Figure A1): The optimal RATE setting once the device turns on is 80 BPM. The pacing rate ranges from 30 to 200 beats per minute (BPM). Turning the RATE knob clockwise increases the rate, and counter-clockwise decreases the rate.
A (Atrial) OUTPUT dial (number 5 in Figure A1: The atrial output ranges from 0.1 to 20 mA. Turn the dial clockwise to increase A OUTPUT. Turn the dial counterclockwise to decrease or turn A OUTPUT OFF. When A OUTPUT is set to OFF, both the atrial output and the atrial sensitivity are turned off (i.e., there is no atrial pacing or sensing).
V (Ventricle) OUTPUT dial (number 6 in Figure A1): The ventricular output ranges from 0.1 to 25 mA. Turn the dial clockwise to increase V OUTPUT. Turn the dial counterclockwise to decrease or turn V OUTPUT to OFF. When V OUTPUT is set to OFF, both the ventricular output and the ventricular sensitivity are turned off (i.e. there is no ventricular pacing or sensing).
PACE LEDs
Adjusting Atrial and Ventricular Sensitivities