Patent ID: 9615800
Date: 2017-04-11
CPC Classifications: A61B

Claim:
1. A system for monitoring a medical patient's condition, comprising: at least one input device, a processing unit and one or more output units, wherein wherein the two or more physiological variable inputs include systolic or mean blood pressure and pulse volume, and the primary physiological variable input is systolic or mean blood pressure; and the R-analysis includes the following steps in order: i. buffer each physiological variable input for a physiological variable R time period, where the physiological variable R time period finishes at a current time, creating buffered physiological variable data for each vital sign input; ii. determine a physiological variable median from each set of buffered physiological variable data; iii. compare a current physiological variable value, which is the physiological variable input at the current time, with the respective physiological variable median to determine a physiological variable difference for each physiological variable; iv. wait a predetermined time, a physiological variable R v. compare each physiological variable difference for each physiological variable and if three or more consecutive physiological variable differences for each physiological variable input are in the same direction from the respective physiological variable median then a trend is confirmed; such that for the R-analysis each physiological variable R time period includes at least 10 measurements of the physiological variable in question and the physiological variable R time period is at least 100 seconds, and the N-analysis includes either steps (vi) to (viii) in order, or steps (ix) and (x) in order: vi. buffer the primary physiological variable input for a primary physiological variable N time period, where the primary physiological variable N time period finishes at the current time, creating buffered primary data; vii. carry out the following calculations: where t t ut ū is a mean primary physiological value from population data; Δ ū is a mean change in the primary physiological variable from the population data over the period of time between t Δu SDu is the standard deviation of the primary physiological variable from the population data; SDΔu is the standard deviation of the change in primary physiological variable from the population data over the period of time between t Cul is a combined primary physiological variable indicator; viii. compare Cul value with a predetermined value SS, if Cul>SS then this confirms a statistically significant change in the primary physiological variable; such that for steps (vi) to (viii) the N-analysis SS is at least 1, and the time period between t 1 and t 2 is at least 10 seconds; ix. buffer the primary physiological variable input for a primary physiological variable N time period, where the primary physiological variable N time period finishes at the current time, creating buffered primary data; x. carry out a principal component analysis to determine whether, over the time period t such that for steps (ix) and (x) the N-analysis using the principal component analysis method the time period between t 1 and t 2 is at least 10 seconds and each SS is greater than or equal to 1; wherein: the processing unit is further configured to output the alert as an alert signal to the or each output unit; and the or each output unit is configured to process the alert signal into an alert output for a user in one or more of the following forms visual, audio, vibratory, or tactile.