Automatic blood analysis apparatus and method

• US 4,134,678 A
• Filed: 03/16/1977
• Issued: 01/16/1979
• Est. Priority Date: 03/16/1977
• Status: Expired due to Term

• Current Assignee: Il Holding SpA (Werfen SA)
• Original Assignee: Instrumentation Lab Co (Instrumentation Lab)
• Inventors: Mountain, Charles F., Stevens, Richard B., Brown, Leslie J., Vasconcelos, Fernando M., DeGironimo, Bruno
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): Punter, Wm. H.
• Application Number:
  US05/778,045
• Time in Patent Office: 671 Days
• Field of Search: 356/39-42, 356/188, 356/201, 356/204-206, 356/36, 356/73, 23/90, 23/214
• US Class Current: 356/39
• CPC Class Codes: F04B 43/1215 having no backing plate (deforming of the tube only by rollers)

Abstract

Method and apparatus for the simultaneous automatic analysis and sequential displaying in digital form of a plurality of parameters of whole or hemolyzed blood samples, such as total hemoglobin, percent oxyhemoglobin, percent carboxyhemoglobin, percent methemoglobin (in each case percent meaning percentage of total hemoglobin) and oxygen content. The apparatus is an electro-optical instrument including a servo-controlled spectral line source, such as a hollow cathode lamp, a laser etc., a ratiometric logarithmic amplifier of minimized dynamic range, a fluid-flow system of improved design that combine to measure the absorbances of blood samples at a plurality of wavelengths defined and generated by the spectral line source, to calculate the above parameters based on the absorbances by the use of a micro-computer and associated circuitry absorbances, to display automatically and digitally one of the parameters, and then to display digitally seriatim the remaining parameters responsive to operator intervention.

Claims

1. An apparatus for analyzing and digitally displaying a plurality of parameters of blood comprising

means for aspirating and simultaneously mixing a sample of blood with a diluent,

means for hemolyzing said mixture,

means for generating spectral lines, said means being servo-controlled so as to maintain the light intensity output of said spectral lines constant,

means for measuring for more than two absorbances of said mixture at at least four wavelengths in the visible spectrum as defined by said means for generating said spectral lines, including means of maintaining said mixture at a constant temperature during said measurement,

means for calculating said plurality of parameters based on said measured absorbances,

means for automatically displaying in digital form one of said calculated parameters, and

means for displaying one at a time the remaining calculated parameters responsive to operator intervention.

2. The apparatus of claim 1 in which said means for generating spectral lines is a hollow cathode lamp.

3. The apparatus of claim 2 in which said hollow cathode lamp comprises a cathode made of thallium (Tl) enveloped in neon (Ne) gas.

4. The apparatus of claim 1 in which said means for generating spectral lines is a laser.

5. The apparatus of claim 1 in which said means for generating spectral lines is a hollow cathode lamp having a cathode made of thallium (Tl) enveloped in neon (Ne) gas and servo-controlled so as to maintain its light intensity output constant.

6. An apparatus for analyzing and digitally displaying a plurality of parameters of whole blood comprising:

means for aspirating and simultaneously mixing a sample of whole blood with a diluent,

means for hemolyzing said mixture,

source means for generating spectral lines of narrow bandwidth,

means for maintaining the output of said spectral line source constant during measurement,

a logarithmic amplifier having input and output,

means for making the logarithmic amplifier output insensitive to variations in the intensity of said source means for generating said spectral lines,

means for measuring for more than two absorbances of said mixture at at least four wavelengths in the visible spectrum as defined by said means for generating said spectral lines, including means of maintaining said mixture at a constant temperature during said measurement,

means for calculating said plurality of parameters based on said measured absorbances,

means for automatically displaying in digital form one of said calculated parameters, and

means for displaying one at a time the remaining calculated parameters responsive to operator intervention.

7. The apparatus of claim 6 further including a means of flushing said mixture after each measurement.

8. The apparatus of claim 7 further including a means of calibrating one of said calculated parameters of said apparatus with a known standard.

9. An automatic blood analysis apparatus comprising

a fluid-flow system including means for aspirating and simultaneously mixing a sample of whole blood with a diluent and conducting the mixture through a hemolyzer and into a cuvette maintained at a constant temperature,

a hollow cathode lamp for generating a plurality of selected wavelengths which will not drift and passing said spectral lines at said selected wavelengths through said cuvette containing said mixture,

sensing means measuring for more than two absorbances of said mixture at at least four wavelengths and at each said selected wavelength and for generating signals responsive thereto,

computer means for receiving signals from said sensing means and for calculating a plurality of parameters of said sample based on said absorbances,

means for automatically displaying in digital form one of said calculated parameters,

and means for displaying one at a time the remaining calculated parameters in response to operator intervention,

in which said means for aspirating and simultaneously mixing a sample includes a multi-segment peristaltic pump having a plurality of pump-cages disposed about a drive shaft for selective rotation therewith and a plurality of flexible tubes wound about said pump-cages, with said pump-cages also acting as pinch-valves precisely to arrest fluid pumped through said tubes.

10. The apparatus of claim 9 in which said hollow cathode lamp comprises a cathode made of thallium (Tl) enveloped in neon (Ne) gas.

11. A method of analyzing and digitally displaying a plurality of parameters of a common sample of whole blood comprising

aspirating and simultaneously mixing a sample of whole blood with a diluent,

hemolyzing said mixture,

bringing said hemolyzed mixture to a constant temperature within a cuvette,

measuring for at least four absorbances of said hemolyzed mixture each at more than two wavelengths in the visible spectrum while maintaining the mixture at said constant temperature,

calculating said plurality of parameters on the basis of said plurality of measured absorbances at each said plurality of wavelengths,

automatically displaying in digital form one of said calculated parameters,

displaying seriatim the operator-selected remaining calculated parameters,

calibrating periodically for a single parameter only of said plurality of parameters, and

introducing a flush solution for removing the aspirated sample.

12. The method of claim 11 in which the range of absorbances at one wavelength is measured and calculated to monitor the efficiency of completion of hemolysis of said mixture.

13. The method of claim 11 in which the range of absorbances at one wavelength is measured and calculated to monitor for the absence of bubbles within said cuvette.

14. A method for the automatic and simultaneous analysis of a common sample of whole blood for a plurality of parameters thereof comprising

aspirating and mixing a sample of whole blood with a diluent,

hemolyzing and bringing to a constant temperature said mixture,

measuring for at least four absorbances of said mixture, each with said absorbance measured at four selected wavelengths,

automatically calculating for said plurality of desired parameters on the basis of said plurality of measured absorbances and pre-programmed values,

automatically converting said calculations into digital form and then displaying one of said converted calculations,

displaying thereafter and one at a time the remaining converted calculated parameters in response to operator intervention,

calibrating periodically for a single parameter only of said plurality of parameters,

introducing a flush solution for removing the aspirated sample, and

monitoring the efficiency of removal of the aspirated mixture from the cuvette.

15. The method of claim 14 in which the range of absorbances at one wavelength is measured and calculated to monitor the efficiency of completion of hemolysis of said mixture.

16. The method of claim 14 in which the range of absorbances at one wavelength is measured and calculated to monitor for the absence of bubbles within said mixture.

17. An apparatus for analyzing and digitally displaying a plurality of parameters of blood comprising

means for aspirating and simultaneously mixing a sample of blood with a diluent,

means for hemolyzing said mixture,

means for generating spectral lines,

means for measuring for more than two absorbances of said mixture at at least four wavelengths in the visible spectrum as defined by said means for generating said spectral lines, including means of maintaining said mixture at a constant temperature during said measurement,

means for calculating said plurality of parameters based on said measured absorbances,

means for automatically displaying in digital form one of said calculated parameters, and

means for displaying one at a time the remaining calculated parameters responsive to operator intervention,

in which said means for aspirating and simultaneously mixing a sample of blood with a diluent includes a multi-segment peristaltic pump having a plurality of pump-cages disposed about a drive shaft for selective rotation therewith and a plurality of flexible tubes wound about said pump-cages, said pump-cages acting as pinch-valves precisely to arrest fluid pumped through said tubes.

18. An automatic blood analysis apparatus comprising

a fluid-flow system including means for introducing and simultaneously mixing a sample and conducting the mixture through a hemolyzer and into a cuvette maintained at a constant temperature,

a source of spectral lines for generating a plurality of selected wavelengths which will not drift and passing said spectral lines at said selected wavelengths through said cuvette containing said mixture,

sensing means for measuring the absorbances of said mixture and for generating signals responsive thereto,

micro-computer means for calculating a plurality of desired parameters of said sample responsive to said signals generated in response to said absorbance measurements, and

means receiving said calculations and converting them for display in digital form one at a time,

in which said fluid-flow system including means for introducing and simultaneously mixing a sample comprises a multi-segment peristaltic pump having a plurality of pump-cages disposed about a drive shaft for selective rotation therewith and in which said source of spectral lines is a hollow cathode lamp having a cathode made of thallium (Tl) enveloped in neon (Ne) gas and servo-controlled so as to maintain its light intensity output constant.