System and method for evaluating physiological parameter data

1. A method of evaluating physiological parameter data, comprising:

monitoring a patient to produce a signal comprising a sequence of numerical values for a physiological parameter over a time period;

calculating an index based at least in part upon the signal;

comparing the calculated index to a reported index, and if the calculated index is greater than the reported index, setting the reported index to the value of the calculated index;

calculating a modulation of the signal, wherein the modulation comprises the difference between a maximum value of the signal and a minimum value of the signal divided by a mean value of the signal over a period of time;

comparing the modulation to a previous value of the modulation of the signal to identify a trend in the modulation, and if the trend corresponds to an undesirable condition, using a first function capable of increasing the reported index; and

providing an indication of a physiological status based at least in part upon the reported index.

2. The method of claim 1 , wherein the index comprises an airway instability index.

3. The method of claim 1 , wherein the period of time comprises a period of time over which a qualified pattern is occurring.

4. A method of evaluating physiological parameter data, comprising:

monitoring a patient to produce a signal comprising a sequence of numerical values for a physiological parameter over a time period;

calculating an index based at least in part upon the signal;

comparing the calculated index to a reported index, and if the calculated index is greater than the reported index, setting the reported index to the value of the calculated index;

calculating a modulation of the signal;

comparing the modulation to a previous value of the modulation of the signal to identify a trend in the modulation, and if the trend corresponds to an undesirable condition, using a first function capable of increasing the reported index, wherein the first function comprises a parabolic growth function, and/or an exponential growth function; and

providing an indication of a physiological status based at least in part upon the reported index.

5. The method of claim 4 , comprising applying a second function capable of decreasing the reported index, if the trend does not correspond to an unfavorable condition.

6. A method of evaluating physiological parameter data, comprising:

monitoring a patient to produce a signal comprising a sequence of numerical values for a physiological parameter over a time period;

calculating an index based at least in part upon the signal;

comparing the calculated index to a reported index, and if the calculated index is greater than the reported index, setting the reported index to the value of the calculated index;

calculating a modulation of the signal,

comparing the modulation to a previous value of the modulation of the signal to identify a trend in the modulation, and if the trend corresponds to an undesirable condition, using a first function capable of increasing the reported index;

applying a second function capable of decreasing the reported index, if the trend does not correspond to an unfavorable condition;

filtering the reported index by a third function, wherein the third function comprises an infinite impulse response filter; and

providing an indication of a physiological status based at least in part upon the reported index.

7. A medical device, comprising:

a microprocessor configured to process a signal associated with at least one physiological parameter of a patient; and

a memory configured to store machine readable instructions which, if executed, are capable of causing the microprocessor to:

calculate an index from the signal;

compare the calculated index to a reported index, and if the calculated index is greater than the reported index, set the reported index to the value of the calculated index;

calculate a modulation of the numerical signal, wherein the modulation comprises the difference between a maximum value of the numerical signal and a minimum value of the numerical signal divided by a mean value of the numerical signal over a period of time;

compare the modulation to a previous value of the modulation to identify a trend in the modulation, and if the trend corresponds to an undesirable condition, increase the reported index using a first function; and

provide an indication of a physiological status based on the reported index.

8. The medical device of claim 7 , wherein the contents of the memory comprises machine readable instructions which, if executed, are capable of causing the microprocessor to apply a second function to decrease the reported index, if the trend does not correspond to an unfavorable condition.

9. The medical device of claim 8 , wherein the machine readable instructions, if executed, are capable of causing the microprocessor to filter the reported index by a third function.

10. The medical device of claim 7 , comprising a network interface unit capable of sending information comprising the numerical signal, and/or the reported index, to a device located on a local area network.

11. The medical device of claim 7 , wherein the index comprises an airway instability index.

12. A medical device, comprising:

a microprocessor configured to process a signal associated with at least one physiological parameter of a patient; and

a memory configured to store machine readable instructions which, if executed, are capable of causing the microprocessor to:

calculate an index from the signal;

compare the calculated index to a reported index, and if the calculated index is greater than the reported index, set the reported index to the value of the calculated index;

calculate a modulation of the numerical signal;

compare the modulation to a previous value of the modulation to identify a trend in the modulation, and if the trend corresponds to an undesirable condition, increase the reported index using a first function, wherein the first function comprises a parabolic growth function, and/or an exponential growth function; and

provide an indication of a physiological status based on the reported index.

13. A medical device, comprising:

a microprocessor configured to process a signal associated with at least one physiological parameter of a patient; and

a memory configured to store machine readable instructions which, if executed, are capable of causing the microprocessor to:

calculate an index from the signal;

compare the calculated index to a reported index, and if the calculated index is greater than the reported index, set the reported index to the value of the calculated index;

calculate a modulation of the numerical signal;

compare the modulation to a previous value of the modulation to identify a trend in the modulation, and if the trend corresponds to an undesirable condition, increase the reported index using a first function;

apply a second function to decrease the reported index, if the trend does not correspond to an unfavorable condition;

filter the reported index by a third function, wherein the third function comprises an infinite impulse response filter; and

provide an indication of a physiological status based on the reported index.

14. A method of evaluating physiological parameter data, comprising:

monitoring a patient to produce a signal comprising a sequence of numerical values for a physiological parameter over a time period;

detecting potential reciprocations by detecting potential reciprocation peaks and nadirs in the sequence of numerical values;

determining whether the potential reciprocations are qualified by comparing metrics of the potential reciprocations with a set of limits and performing a linear qualification function;

tracking a number of qualified reciprocations identified within a window of time and calculating an index when the number of qualified reciprocations identified within the window of time reaches or surpasses a limit;

comparing the calculated index to a reported index, and if the calculated index is greater than the reported index, setting the reported index to the value of the calculated index; and

providing an indication of a physiological status based at least in part upon the reported index.

15. The method of claim 14 , comprising:

calculating a modulation of the signal; and

comparing the modulation to a previous value of the modulation to identify a trend in the modulation and if the trend corresponds to an undesirable condition, using a first function capable of increasing the reported index.

16. The method of claim 14 , comprising calculating the index based at least in part upon an average magnitude of all qualified reciprocations within a time period relative to the current time, an average of a fixed number of the highest reciprocation peaks of qualified reciprocations within the time period, and/or an average of a fixed number of the highest reciprocation nadirs of qualified reciprocations within the time period, and/or combinations thereof.

17. The method of claim 14 , wherein the window of time may be defined based on historical values.