Patent ID: 11865351
Assignee: PHYSIO-CONTROL, INC.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. An external defibrillator comprising:
a measurement circuit configured to:
detect, during a first time interval, a first electrocardiogram (ECG) signal of an individual via a first ECG channel, and
detect, during the first time interval, a second ECG signal of the individual via a second ECG channel, and
detect, during a second time interval, a third ECG signal of the individual via the first ECG channel;

a discharge circuit configured to output an electrical shock to the individual;
first conductors configured to receive a first voltage corresponding to the first ECG channel;
second conductors configured to receive a second voltage corresponding to the second ECG channel;
a first switch connected to the first conductors and to the measurement circuit;
a second switch connected to the second conductors and to the measurement circuit; and
a processor configured to:
identify a baseline of the first ECG signal by performing low-pass filtering on the first ECG signal;
identify a baseline of the second ECG signal by performing low-pass filtering on the second ECG signal;
determine a shift of the baseline of the first ECG signal during the first time interval;
determine a shift of the baseline of the second ECG signal during the second time interval;
compare the shift of the baseline of the first ECG signal to the shift of the baseline of the second ECG signal;
in response to comparing the shift of the baseline of the first ECG signal to the shift of the baseline of the second ECG signal, select first ECG channel;
in response to selecting the first ECG channel, open the second switch, thereby disconnecting the second conductors from the measurement circuit;
in response to selecting the first ECG channel, determine that the third ECG signal comprises ventricular fibrillation (VF) or ventricular tachycardia (VT); and
in response to determining that the third ECG signal comprises VF or VT, cause the discharge circuit to output the electrical shock.