Philips Heartstart XLT, Руководство по обслуживанию

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System Functional Descriptions
6 - 10 Theory of Operation
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At any time during delivery of the shock, it detects an open circuit
(voltage too high for that point in the waveform) or a short circuit
(current too high for that point in the waveform).
Should any of these conditions be detected, the Power PCA terminates deliv-
ery of the waveform and disarms the capacitor. The problem is reported to the
Control PCA, which displays and/or prints the appropriate messages.
Another safety feature is the presence of a identification resistor in the pads
cable. If the unit does not sense that resistance, it gives a
Cable Off
message
and will not charge the capacitor.
Delivering synchronized cardioversion
Synchronized cardioversion operates the same as delivering a shock, except
that the shock must be synchronized to the R wave of the ECG. The Control
PCA is responsible for detecting the R wave and placing markers on the
printed strip and on the display to indicate the timing of the proposed cardio-
version shock.
To deliver a synchronized shock, key #3 (
SHOCK
) is pressed and held until the
next time an R wave is detected. When both events occur (key press and R
wave) the Control PCA directs the Power PCA to deliver the shock.