Perfusion index smoother

Abstract

An embodiment of the present disclosure seeks to smooth a perfusion index measurement through use of a baseline perfusion index measurement and/or through the use of multiple PI calculations. The combination of the baseline perfusion index measurement reduces an error between a calculated measurement of PI and actual conditions.

1 - 17 . (canceled) 
     
     
         18 . A patient monitoring system for determining physiological parameters, the system comprising:
 an input capable of acquiring data responsive to intensity signals;   a data processor to smoothen the acquired data and produce an indication of blood flow, wherein the data processor is configured to:
 determine a first indication of amplitude data based on a first rule corresponding to a pulse by pulse calculation; 
 determine a second indication of amplitude data based on a second rule corresponding to a combination of pulses calculation; 
 determine a final indication of amplitude data based on a third rule corresponding to the first and second indications; and 
 output the final indication as an indication of blood flow. 
   
     
     
         19 . The system of  claim 18 , wherein the combination of pulses in the second indication of amplitude data comprises a maximum and minimum amplitude of a plurality of pulses. 
     
     
         20 . The system of  claim 18 , wherein the processor is configured to determine the final indication based on selecting a lowest indication of amplitude data. 
     
     
         21 . The system of  claim 18 , wherein the third rule is determined by averaging the first and the second indications of amplitude. 
     
     
         22 . The system of  claim 18 , wherein the indication of blood flow is a perfusion index. 
     
     
         23 . The system of  claim 18 , wherein the processor determines one or more indication of pulse information from the intensity signals. 
     
     
         24 . The system of  claim 23 , wherein the one or more indication of pulse information is used in the first rule to determine the first indication of amplitude data. 
     
     
         25 . An oximeter system for determining an indication of a physiological condition, the oximeter system comprising:
 an input configured to receive data responsive to intensity signals; and   a data processor in communication with the input, the processor configured to:
 calculate at least two indications of blood flow based on the data responsive to intensity signals using at least two different rules, wherein at least one of the rules performs analysis based on pulse by pulse determination; and 
 determine a final indication of blood flow based on the at least two indications of blood flow, the final indication determined based on the at least two indications of the blood flow. 
   
     
     
         26 . The system of  claim 25 , wherein the indication of blood flow is a perfusion index. 
     
     
         27 . The system of  claim 25 , wherein at least another of the rules performs analysis based on a combination of pulses. 
     
     
         28 . The system of  claim 25 , wherein the data processor is configured to determine the final indication using amplitude data. 
     
     
         29 . The system of  claim 28 , wherein the amplitude data comprises a maximum and minimum amplitude of at least one pulse.