Method and analyzer to correct for unknown interferences in a patient blood sample

A computerized method performed by a processor executing computer executable code stored on a computer readable medium, comprising:

• actuating a plasma separator to separate a plasma sample from a whole blood sample;
• actuating a detector to obtain first data indicative of a first spectrophotometer measurement of the plasma sample;
• actuating the detector to obtain second data indicative of a second spectrophotometer measurement of a lysed blood sample obtained from the whole blood sample;
• and
• determining a total absorbance spectrum for the whole blood sample in which the first data is adjusted by the second data to remove effects in the first spectrophotometer measurement of the plasma sample of one or more unknown extracellular interferents in the whole blood sample.

A blood analyzer, comprising:

• a detector within a path of an optical signal from a light source, the detector configured to generate data indicative of intensity of the optical signal at wavelengths within a range from 450 nm to 680 nm;
• a transparent sample vessel positioned within the path between the light source and the detector such that the optical signal passes through the transparent sample vessel prior to being received by the detector;
• a plasma separator to separate plasma from a blood sample to create a plasma sample;
• a dispenser adapted to pass a first portion of the blood sample into the transparent sample vessel at a first instance of time, the first portion being whole blood or lysed blood, and to pass the plasma sample into the transparent sample vessel at a second instance of time;
• and
• a controller having a processor executing logic that when executed by the processor causes the processor to obtain first data generated by the detector indicative of the optical signal passing through the first portion of the blood sample, and second data generated by the detector indicative of the optical signal passing through the plasma sample, the logic causing the processor to calculate a total absorbance spectrum in which the first data is adjusted by the second data to remove effects of one or more unknown extracellular interferents in the blood sample.