Alarm setting derived from the variability in signal characteristics
A method for creating alarm signals based on time-series signal behavior determined from real-time discrete data obtained from a medical device. In one embodiment the method includes identifying patterns in preceding time-series measurement threshold breaches in clinical readings obtained from said medical device when associated with a particular patient, and initiating an alarm signal to a front-line clinician based on the preceding quantity of threshold breaches.
1. A method for creating alarm signals based on time-series signal behavior of real-time discrete data obtained from a medical device comprising:
continuously monitoring a patient's clinical reading via data obtained from the medical device;
continuously calculating and updating a current running average over a defined time interval of the data obtained from the medical device based on a predetermined running average time interval window, wherein the calculated current running average varies over time;
continuously setting a current upper and a lower limit threshold for the clinical reading in response to the calculated current running average, wherein the current set upper limit threshold and/or the current set lower limit threshold varies over time;
determining, over a predetermined monitoring time period, one or more breaches of at least one of a current set upper limit threshold and a current set lower limit threshold, wherein each breach is a breach event;
calculating, over the predetermined monitoring time period, the total number of breach events for at least one of the upper limit threshold and the lower limit threshold;
issuing an alarm when the calculated total number of breach events for at least one of the upper limit threshold and the lower limit threshold exceeds a predetermined breach event threshold; and
calculating a change in at least one of the upper and lower limit thresholds when the calculated total number of breach events exceeds a predetermined amount.
2. The method of claim 1 , wherein a new upper limit threshold and a new lower limit threshold in subsequent defined time intervals are in response to a percentage of the running average, representative of a normal range of variability associated with measurements of a specific patient.
3. The method of claim 2 , wherein the percentage is between 10% and 30% inclusive.
4. The method of claim 1 , further comprising:
identifying time points corresponding to the breaches of the upper and lower limit threshold; and
determining a quantity of cumulative breaches based on a time frame.
5. A method for creating alarm signals based on time-series signal behavior of real-time discrete data obtained from a medical device comprising:
continuously monitoring a patient's clinical reading via data obtained from the medical device;
continuously calculating and updating a current running average over a defined time interval of the data obtained from the medical device based on a predetermined running average time interval window, wherein the calculated current running average varies over time;
continuously setting a current upper and a lower limit threshold for the clinical reading in response to the calculated current running average, wherein the current set upper limit threshold and/or the current set lower limit threshold varies over time;
determining, over a predetermined monitoring time period, one or more breaches of at least one of a current set upper limit threshold and a current set lower limit threshold, wherein each breach is a breach event;
calculating, over the predetermined monitoring time period, the total number of breach events for at least one of the upper limit threshold and the lower limit threshold;
calculating a change in at least one of the upper and lower limit thresholds when the number of breaches of the upper and lower respective threshold exceeds a predetermined amount;
generating a relative weight for at least one breach of the one or more breaches, wherein the relative weight of the at least one breach is a function of difference between a measurement of a magnitude of the at least one breach of the upper and the lower limit threshold and a current value of the running average; and
generating an alarm in response to the number of breaches having a weighted value greater than a specified limit threshold value.
6. The method of claim 5 , wherein a new upper limit threshold and a new lower limit threshold in subsequent defined time intervals are in response to a percentage of the running average, representative of a normal range of variability associated with measurements of a specific patient.
7. The method of claim 6 , wherein the percentage is between 10% and 30% inclusive.
8. The method of claim 5 further comprising:
identifying time points corresponding to the breaches of the upper and lower limit threshold; and
determining a quantity of cumulative breaches based on a time frame.