Defibrillator with protocol for selectively interrupting CPR

1. A method for optimizing guidance instructions for delivering cardio-pulmonary resuscitation and electrotherapy from a defibrillator comprising the steps of:

providing a source of patient ECG signals received during a CPR period;

estimating from the patient ECG signals the likelihood of a shockable rhythm existent during the CPR period, wherein the estimating step comprises a vRhythm calculation which includes the effects of CPR artifact to determine a return of spontaneous circulation (ROSC) score, the ROSC score indicating the likelihood of a shockable rhythm existent during the CPR period, and wherein the vRhythm calculation includes a frequency bandwidth which acts to suppress the effects of CPR artifact on the ROSC score;

determining whether CPR should be interrupted prior to the end of the CPR period to deliver electrotherapy based on the estimating step; and

providing an output instruction from the defibrillator to stop CPR prior to the end of the CPR period based on the determining step.

2. The method of claim 1 , further comprising the steps of:

earlier estimating from the patient ECG signals the likelihood of a shockable rhythm existent during the CPR period,

wherein the determining step is further based on the earlier estimating step.

3. The method of claim 1 , further comprising the step of obtaining an input from a second signal source,

wherein the determining step is further based on the obtaining an input step.

4. The method of claim 3 , wherein the second signal source is selected from one of the group of a common mode current signal, a patient small-signal impedance signal, and a patient chest will acceleration signal.

5. A method for optimizing guidance instructions for delivering cardio-pulmonary resuscitation and electrotherapy from a defibrillator comprising the steps of:

providing a source of patient ECG signals received during a CPR period;

estimating from the patient ECG signals the likelihood of a shockable rhythm existent during the CPR period;

determining whether CPR should be interrupted prior to the end of the CPR period to deliver electrotherapy based on the estimating step;

providing an output instruction from the defibrillator to stop CPR prior to the end of the CPR period based on the determining step;

analyzing the ECG signals obtained subsequent to the providing step to determine whether a shock is recommended or a shock is not recommended;

adjusting a parameter in the determining step if both a shockable rhythm is determined from the determining step and a shock is not recommended in the analyzing step; and

issuing an output instruction to resume CPR,

wherein the adjusting step parameter is selected from the group comprising a filter parameter and a threshold comparison parameter.

6. A method for optimizing guidance instructions for delivering cardio-pulmonary resuscitation and electrotherapy from a defibrillator comprising the steps of:

providing a source of patient ECG signals received during a CPR period;

estimating from the patient ECG signals the likelihood of a shockable rhythm existent during the CPR period;

determining whether CPR should be interrupted prior to the end of the CPR period to deliver electrotherapy based on the estimating step;

providing an output instruction from the defibrillator to stop CPR prior to the end of the CPR period based on the determining step;

analyzing the ECG signals obtained subsequent to the providing step to determine whether a shock is recommended or a shock is not recommended;

adjusting a parameter in the determining step if both a shockable rhythm is determined from the determining step and a shock is not recommended in the analyzing step;

issuing an output instruction to resume CPR; and

disabling the determining step if both a shockable rhythm is determined from the determining step and a shock is not recommended in the analyzing step.