Analyte detection systems and methods using multiple measurements

Abstract

In certain embodiments, a sampling assembly is for use with a main analyzer. The main analyzer is configured to sense an analyte in a body fluid obtained from a patient through a first fluid passageway extending from the main analyzer. The sampling assembly includes an instrument portion separate from the main analyzer and including at least one sensor. The instrument portion is removably engaged with the first fluid passageway. The at least one sensor is in sensing engagement with the first fluid passageway such that the at least one sensor can sense a property of a fluid within the first fluid passageway.

1 . An apparatus for analyzing bodily fluid, the apparatus comprising:
 a fluid handling network comprising:
 a patient connector configured to maintain fluid communication with the bodily fluid in a patient; and 
 at least one passageway configured to connect between the patient connector and a sample analysis chamber; 
   at least one pump in operative engagement with the fluid handling network, the at least one pump having a sample draw mode in which the at least one pump is operable to draw a sample of the bodily fluid from the patient through the at least one passageway, wherein the at least one pump is configured to direct an analysis portion of the sample to the sample analysis chamber;   an analyzer configured to obtain at least one mid-infrared spectroscopic characterization of the analysis portion of the sample while the sample is located inside the sample analysis chamber;   a waste chamber configured to receive the analysis portion from the sample analysis chamber after the analysis portion is analyzed by the analyzer; and   a fluid sensor located between the patient connector and the sample analysis chamber and spaced from the sample analysis chamber, the fluid sensor configured to sense a property of the bodily fluid within the at least one passageway while the bodily fluid is located outside of the sample analysis chamber.   
     
     
         2 . The apparatus of  claim 1 , wherein the bodily fluid is undiluted when the fluid sensor senses the property of the bodily fluid within the at least one passageway. 
     
     
         3 . The apparatus of  claim 1 , wherein a return portion of the sample is returned to the patient. 
     
     
         4 . The apparatus of  claim 3 , wherein the fluid sensor is configured to sense a property of the return portion of the sample. 
     
     
         5 . The apparatus of  claim 1 , further comprising a controller configured to operate the at least one pump in the sample draw mode at intervals. 
     
     
         6 . The apparatus of  claim 5 , wherein the intervals are irregular. 
     
     
         7 . The apparatus of  claim 1 , wherein the fluid sensor is located at or near a patient end of the fluid handling network. 
     
     
         8 . The apparatus of  claim 1 , wherein the fluid sensor comprises a colorimetric sensor, a hemoglobin sensor, a hematocrit sensor, a pressure sensor, a bubble sensor, a dilution sensor, or a combination of sensors. 
     
     
         9 . The apparatus of  claim 1 , wherein the analyzer is configured to use the mid-infrared spectroscopic characterization to estimate the level of at least one analyte. 
     
     
         10 . The apparatus of  claim 9 , wherein the at least one analyte is glucose. 
     
     
         11 . The apparatus of  claim 1 , wherein the analyzer comprises a mid-infrared source configured to emit infrared radiation at wavelengths between about 1.5 μm and about 11 μm. 
     
     
         12 . The apparatus of  claim 11 , wherein the mid-infrared source is configured to emit infrared wavelengths between 4 μm and 11 μm. 
     
     
         13 . The apparatus of  claim 1 , wherein the analyzer comprises at least one optical filter. 
     
     
         14 . A method for analyzing a bodily fluid, the method comprising:
 drawing the bodily fluid from a patient and into a fluid handling apparatus that comprises a sample chamber, wherein the fluid handling apparatus is configured to maintain physical connectivity with the patient;   analyzing at least one portion of the bodily fluid using a fluid sensor that is positioned to analyze the at least one portion while the at least one portion is located inside the fluid handling apparatus but outside of the sample chamber;   directing at least an analysis portion of the bodily fluid to the sample chamber; and   analyzing the analysis portion of the bodily fluid inside the sample chamber by obtaining at least one spectroscopic measurement.   
     
     
         15 . The method of  claim 14 , further comprising delivering the analysis portion to a waste receptacle after analyzing the analysis portion of the bodily fluid inside the sample chamber by obtaining at least one spectroscopic measurement. 
     
     
         16 . The method of  claim 14 , wherein the at least one portion of the bodily fluid which is analyzed by the fluid sensor is undiluted. 
     
     
         17 . The method of  claim 14 , wherein obtaining the at least one spectroscopic measurement comprises analyzing the analysis portion with infrared wavelengths. 
     
     
         18 . The method of  claim 17 , wherein obtaining the at least one spectroscopic measurement comprises analyzing the analysis portion with mid-infrared wavelengths. 
     
     
         19 . The method of  claim 18 , wherein the mid-infrared wavelengths have wavelengths between 1.5 μm and 11 μm. 
     
     
         20 . The method of  claim 14 , wherein a controller causes or enables drawing the bodily fluid from the patient at regular or irregular intervals. 
     
     
         21 . A method for manufacturing a bodily fluid analysis system, the method comprising:
 providing a fluid handling network, wherein the fluid handling network comprises a patient end configured to maintain fluid communication with a bodily fluid in a patient and wherein the fluid handling network comprises a sample chamber;   providing a sampling unit configured to operatively connect to the fluid handling network, wherein the sampling unit has a sample obtaining mode in which the sampling unit is operable to obtain a sample of bodily fluid from the patient through the patient end;   providing a spectroscopic analyzer positioned to analyze an analysis portion of the sample while the analysis portion is located inside the sample chamber; and   providing a fluid sensor positioned to analyze the bodily fluid while the bodily fluid is located outside of the sample chamber.   
     
     
         22 . The method of  claim 21 , wherein the sampling unit comprises at least one pump. 
     
     
         23 . The method of  claim 21 , further comprising providing a control apparatus that is in operative engagement with the sampling unit such that the control apparatus is capable of sending signals to the sampling unit which allow the bodily fluid analysis system to obtain multiple samples of the bodily fluid at intervals. 
     
     
         24 . The method of  claim 21 , further comprising providing a waste receptacle that is coupled to the sample chamber, wherein the bodily fluid analysis system is configured to enable discharging the sample into the waste receptacle after the spectroscopic analyzer analyzes the sample. 
     
     
         25 . The method of  claim 21 , wherein the spectroscopic analyzer comprises a mid-infrared source configured to emit wavelengths between 1.5 μm and 8 μm.