Method and apparatus for deriving oxygen association rate curves for blood samples

Abstract

A method and apparatus for deriving an oxygen association .[.rate.]. curve for a blood sample wherein the sample is introduced into a transparent-walled cell and is deoxygenated by contact with a deoxygenated fluorocarbon material. The cell is located in the optical path of two time-shared respective monochromatic beams, one having a wavelength at which there is substantially no change in absorbance as between oxygenated and deoxygenated blood and the other having a wavelength at which there is a relatively large change in absorbance as between oxygenated and deoxygenated blood. The difference in absorbance through the cell of the two wavelengths is measured and recorded while oxygenated fluorocarbon titrant material is pumped through the cell, the cell having a restricted flow passage for the titrant material which acts to separate the blood therefrom and retain it in the cell while the titration is taking place.

What is claimed is: 
     
       1. A method of deriving an oxygen association rate curve for a blood sample comprising deoxygenating the sample, introducing an oxygenating agent into the sample, passing two respective monochromatic wavelengths through the sample while it is being oxygenated, one wavelength at which there is substantially no change in absorbance as between oxygenated and deoxygenated blood and the other wavelength at which there is a relatively large change in absorbance as between oxygenated and deoxygenated blood, and plotting the difference in absorbance for the two wavelengths with time as the sample is being oxygenated. 
     
     
       2. The method of claim 1, and wherein the blood sample and the oxygenating agent are agitated while oxygenation of the blood sample is taking place. 
     
     
       3. The method of claim 1, and wherein said one wavelength has a value of approximately 448 nm and said other wavelength has a value of approximately 439 nm. 
     
     
       4. The method of claim 1, and wherein the oxygenating agent comprises oxygenated fluorocarbon liquid material. 
     
     
       5. The method of claim 4, and wherein deoxygenation of the sample comprises exposing it to deoxygenated fluorocarbon liquid material. .Iadd. 6. A method of deriving oxygen association curve information for a blood sample, said method comprising disposing a blood sample within a treatment cell, introducing available oxygen into said cell in a first concentration, varying said first concentration of oxygen within said cell over a period of time to provide exposure of said blood sample to varying concentrations of oxygen, passing first and second light beams through said sample during said time period, said first light beam having a wavelength such that there is substantially no difference in absorbance of said wavelength by said blood sample in the oxygenated and deoxygenated states, respectively, of said blood, said second light beam having a wavelength such that there is a relatively large difference in absorbance of said wavelength by said blood sample in the oxygenated and deoxygenated states, respectively, of said blood, and determining the changes in oxygen association of said blood with respect to the changes in oxygen concentration within said cell by sensing the differences in the respective degrees of absorption of said first and second beams by said blood as said oxygen concentration is changed. .Iaddend..Iadd. 7. A method as defined in claim 6 wherein varying said concentration of oxygen includes the steps of substantially deoxygenating said sample and thereafter introducing oxygenating materials into said cell in gradually increasing concentrations until said sample is substantially completely oxygenated. .Iaddend. .Iadd. 8. A method as defined in claim 6 wherein said one wavelength has a value of approximately 448 nm and said other wavelength has a value of approximately 439 nm. .Iaddend..Iadd. 9. A method as defined in claim 1 wherein said available oxygen is introduced in the form of an oxygenating agent, and wherein the blood sample and said oxygenating agent are agitated while oxygenation of the blood sample is taking place. .Iaddend..Iadd. 10. A method as defined in claim 1 wherein said available oxygen is introduced in the form of an oxygenating agent, and wherein the oxygenating agent comprises oxygenating flurocarbon liquidated material. .Iaddend..Iadd. 11. A method as defined in claim 1 which further includes the step of deoxygenating said sample prior to oxygenating said sample, said deoxygenating being accomplished by exposing said sample to deoxygenating fluorocarbon liquidated material. .Iaddend. .Iadd. 12. A method of deriving oxygen association curve information for a blood sample, said method comprising disposing a blood sample within a treatment cell, introducing available oxygen into said cell in a first concentration, varying said first concentration of oxygen within said cell over a period of time to provide exposure of said blood sample to varying concentrations of oxygen, passing first and second light beams through said sample during said time period, said first light beam having a first wavelength selected so as to have a first characteristic difference in absorbance thereof by said blood sample as between the oxygenated and deoxygenated states thereof, said second light beam having a second wavelength selected so as to have a second characteristic difference in absorbance of said wavelength by said blood sample as between the oxygenated and deoxygenated states thereof, and determining the changes in oxygen association of said blood with respect to the changes in oxygen concentration within said cell by sensing the differences in the respective degrees of absorption of said first and second beams by said blood as said oxygen concentration is changed. .Iaddend..Iadd. 13. A method as defined in claim 12 wherein varying said concentration of oxygen includes the steps of substantially deoxygenating said sample and thereafter introducing oxygenating materials into said cell in gradually increasing concentrations until said sample is substantially completely oxygenated. .Iaddend..Iadd. 14. A method as defined in claim 12 wherein said first wavelength has a value of approximately 448 nm and said second wavelength has a value of approximately 439 nm. .Iaddend. .Iadd. 15. A method of deriving oxygen association curve information for a blood sample, said method comprising disposing a blood sample within a treatment cell, introducing available oxygen into said cell in a first concentration, varying said first concentration of oxygen within said cell over a period of time to provide exposure of said blood sample to varying concentrations of oxygen, passing first and second light beams through said sample during said time period, said first light beam having a first wavelength selected so as to have a first, characteristic difference in absorbance thereof by said blood sample as between the oxygenated and deoxygenated states, respectively, of said blood, said second light beam having a second wavelength selected so as to have a second characteristic difference in absorbance of said wavelength by said blood sample as between the oxygenated and deoxygenated states, respectively, of said blood, and determining the changes in oxygen association of said blood with respect to the changes in oxygen concentration within said cell by sensing the differences in the respective degrees of absorption of said first and second beams by said blood as said oxygen concentration is changed. .Iaddend..Iadd. 16. A method as defined in claim 15 wherein varying said concentration of oxygen includes the steps of substantially deoxygenating said sample and thereafter introducing oxygenating materials into said cell in gradually increasing concentrations until said sample is substantially completely oxygenated. .Iaddend. .Iadd. 17. A method as defined in claim 15 wherein said first wavelength has a value of approximately 448 nm and said second wavelength has a value of approximately 439 nm. .Iaddend.