Patent ID: 8989853
Filing Date: 2015-03-24
Classification: A61B

Abstract:
1. A patient monitor comprising: an electrocardiograph monitoring an electrocardiographic signal of a patient; a secondary physiological signal monitor monitoring a second physiological signal of the patient concurrently with the electrocardiograph monitoring the electrocardiographic signal of the patient; an alarm condition detector configured to detect an asystole alarm condition in which the electrocardiographic signal of the patient does not exhibit pulsatile behavior indicative of a beating heart; an alarm condition validator configured to validate the asystole alarm condition based on whether a pulse regularity index (PRI) quantifying pulse regularity of a pulsatile component of the concurrently monitored second physiological signal of the patient satisfies a validation criterion, the PRI being computed based on a set of N+1 pulses including (i) a current pulse of the pulsatile component of the monitored second physiological signal and (ii) N immediately preceding pulses of the pulsatile component of the monitored second physiological signal, where N is a positive integer greater than or equal to two, wherein the alarm condition validator is configured to define one or more pulses of the set of N+1 pulses as a forced pulse detection conditional upon the pulsatile component of the monitored second physiological signal having no pulses in a preselected time interval and wherein the PRI is computed based on (i) amplitude information for the pulses of the set of N+1 pulses including any forced pulse detections, (ii) time interval information between the pulses of the set of N+1 pulses including any forced pulse detections, and (iii) the number of forced pulse detections; and an alarm indicator configured to generate a human perceptible alarm conditional upon both the alarm condition detector detecting an asystole alarm condition and the asystole alarm condition validator validating the asystole alarm condition.