Techniques for managing inconclusive or disagreeing results in analyses of physiological parameters

A monitor-defibrillator, comprising:

• a detection circuit configured to detect an electrocardiogram (ECG) of a subject;
• an analog to digital converter (ADC) configured to convert the ECG to unfiltered data;
• an input device configured to receive an input signal from a user;
• a discharge circuit configured to output an electrical shock to the subject in response to the input device receiving the input signal;
• a transceiver configured to receive a signal from a mechanical chest compression device administering chest compressions to the subject, the signal indicating a frequency of the chest compressions;
• a display;
• and a processor configured to:
• generate first filtered data by removing a chest compression artifact from the unfiltered data using a first filter;
• determine a first shock index by analyzing the first filtered data;
• generate a second filter comprising a comb filter rejecting the frequency and harmonics of the frequency, the second filter being different than the first filter;
• generate second filtered data by applying the second filter to the unfiltered data;
• determine that the first shock index is greater than a first threshold and lower than a second threshold;
• in response to determining that the first shock index is greater than the first threshold and lower than the second threshold, cause the display to visually present the second filtered data;
• and upon expiration of a time period after outputting the second filtered data:
• determine a second shock index by analyzing the first filtered data;
• determine that the second shock index is less than the first threshold or greater than the second threshold;
• and in response to determining that the second shock index is less than the first threshold or greater than the second threshold, cause the display to output a recommendation to initiate the electrical shock using the input signal.