Apparatus and control kit for analyzing blood sample values including hematocrit
First Claim
1. A method for determining the hematocrit value of a blood sample by:
- (a) providing apparatus comprising a liquid flow path, means in the flow path for generating an electrical signal representative of the electrical conductivity of liquid in the Path, and means in the flow path for obtaining an electrical signal representative of the concentration of at least one ion species in liquid in the flow path;
(b) introducing standardizing solution in the flow Path having a known concentration of said ion species and having a conductivity indicative of a known equivalent hematocrit value, and obtaining a signal representative of said standardizing solution conductivity and obtaining a signal representative of said known ion species concentration;
(c) either before or after introducing the standardizing solution, introducing the sample in the flow path and obtaining an electric signal representative of the sample conductivity and an electric signal representative of the sample ion-species concentration; and
(e) deriving a tentative sample hematocrit value responsive to the sample conductivity signal, with reference to said standardizing conductivity signal and to said known standardizing equivalent hematocrit value; and
(f) correcting said tentative sample hematocrit value with reference to said sample and standardizing ion concentration signals and to said known ion concentration value.
4 Assignments
0 Petitions
Accused Products
Abstract
Hematocrit level of a blood sample is measured by flowing the sample along a liquid flow path and using electrodes in the flow path to obtain electrical signals representative of the sample'"'"'s electrical conductivity and of the concentration of an ion species in the path, either before or after the sample measurement. Electrical signals are obtained for standardizing solution conductivity and ion species concentration. A tentative sample hematocrit value is derived from the sample and standardizing conductivity signals. Then the tentative hematocrit value is corrected with reference to the sample and standardizing ion concentration signals and to the known standardizing solution ion concentration value. A control solution of the ion species at known concentration is used for evaluating the hematocrit detection apparatus; the solution also includes an ion activity enhancing agent. A removable septum assembly is used in a blood sample component measuring apparatus in which at least two standardizing solutions are introduced into the flow path. The septum assembly comprises: (a) chamber-defining members, which define a plurality of chambers, the members being permanently attached to each other; and (b) flexible septa positioned between the chambers, each septum having a slit, the slits being aligned to sealably receive therethrough an elongated probe connected to a flush fluid and each remaining chamber being connected to a standardizing fluid introducing lines, the septum assembly being removably attached as a unit to the apparatus which includes means for releasably attaching the septum assembly in position to receive the probe through the slits.
131 Citations
30 Claims
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1. A method for determining the hematocrit value of a blood sample by:
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(a) providing apparatus comprising a liquid flow path, means in the flow path for generating an electrical signal representative of the electrical conductivity of liquid in the Path, and means in the flow path for obtaining an electrical signal representative of the concentration of at least one ion species in liquid in the flow path; (b) introducing standardizing solution in the flow Path having a known concentration of said ion species and having a conductivity indicative of a known equivalent hematocrit value, and obtaining a signal representative of said standardizing solution conductivity and obtaining a signal representative of said known ion species concentration; (c) either before or after introducing the standardizing solution, introducing the sample in the flow path and obtaining an electric signal representative of the sample conductivity and an electric signal representative of the sample ion-species concentration; and (e) deriving a tentative sample hematocrit value responsive to the sample conductivity signal, with reference to said standardizing conductivity signal and to said known standardizing equivalent hematocrit value; and (f) correcting said tentative sample hematocrit value with reference to said sample and standardizing ion concentration signals and to said known ion concentration value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. Apparatus for determining hematocrit value in a blood sample comprising:
- (1) means for providing a fluid flow path;
(2) means in said flow path for providing an electrical signal representative of the conductivity of liquid passing along said flow path;
(3) means in said flow path for providing a signal representative of the concentration of an ion species in liquid passing along said flow path;
(4) means for introducing said blood sample into said flow path to obtain a signal representative of sample conductivity and of sample ion species concentration;
(5) means for introducing into said flow path a standardizing solution having a known concentration of an ion species and having a conductivity representative of a known equivalent hematocrit value;
(6) means for deriving a signal representative of a tentative sample hematocrit value from the sample conductivity signal, with reference to the standardizing conductivity signal and to the standardizing equivalent hematocrit value; and
(7) means for correcting said tentative sample hematocrit value with reference to said standardizing and sample ion concentration signals and to said known standardizing ion concentration. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
- (1) means for providing a fluid flow path;
- 18. A control solution kit for evaluating apparatus that determines a tentative level for the hematocrit of a blood sample by determining the sample conductivity and correcting said tentative level with reference to a sample ion species concentration level, said kit comprising an aqueous solution comprising said ion species and an ion activity enhancing agent, said solution having a known concentration of said ion and a known equivalent hematocrit value.
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23. Apparatus for determining the concentration of a blood sample component comprising means defining a flow path, means in said path for generating an electrical signal representative of said component concentration in fluids in said path, means for introducing at least two standardizing solutions in said flow path, and means for comparing the sample concentration signal with the standardizing concentration signals wherein said apparatus further comprises a septum assembly connected to said flow path means and to said standardizing fluid introducing means, said septum assembly comprising:
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(a) chamber-defining members, said members defining a plurality of chambers, said members being permanently attached to each other; and (b) flexible septa positioned between said chambers, each said septum having a slit, said slits being aligned to sealably receive therethrough an elongated probe connected to said flow path, each said chamber being connected to a said standardizing fluid introducing means, said septum assembly being removably attached as a unit to said apparatus, said apparatus including means for releasably attaching said septum assembly in position to receive said probe through said slits. - View Dependent Claims (24, 25, 26)
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- 27. A septum assembly comprising means for removable attachment to apparatus for measuring the concentration of blood sample components, said assembly comprising chamber-defining members defining a plurality of chambers, said members being permanently attached to each other, and flexible septa positioned between said chambers, each said septa having a sealable slit, said slits being aligned, each said septum assembly chamber comprising means for connection to a standardizing fluid source, said septum assembly further comprising a means for releasable attachment as a unit to said analyzer in position to sealably receive through said aligned slits a hollow elongated analyzer probe.
Specification