Method and apparatus for analyzing blood

• US 5,089,421 A
• Filed: 03/30/1990
• Issued: 02/18/1992
• Est. Priority Date: 02/06/1989
• Status: Expired due to Fees

• Current Assignee: Susan Dieffenbach
• Original Assignee: Susan Dieffenbach
• Inventors: Dieffenbach, Susan
• Primary Examiner(s): Hill, Jr., Robert J.
• Assistant Examiner(s): REDDING, DAVID A
• Application Number:
  US07/502,251
• Time in Patent Office: 690 Days
• Field of Search: 436/68, 436/63, 128/632-635, 128/765
• US Class Current: 436/68
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/15003 for venous or arterial blood
• CPC Class Codes: A61B 5/150992 Blood sampling from a fluid line external to a patient, such as a catheter line, combined with an infusion line; blood sampling from indwelling needle sets, e.g. sealable ports, luer couplings, valves tubing connectors and couplings A61M39/00
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: G01N 33/4925 measuring blood gas content, e.g. O2, CO2 , HCO3

Abstract

An apparatus for analyzing blood comprises a conduit formed with a passageway. The conduit is also formed with an inlet, an outlet and an aperture, each of which are in fluid communication with the passageway. An adapter is threadably engageable with the conduit to hold a membrane therebetween over the aperture. A syringe is engageable with the outlet to draw blood into the passageway through the inlet and into contact with the membrane. The electrode of a blood gas analyzer is engageable with the adapter to position the electrode against the side of the membrane opposite the side in contact with the blood for analyzing the oxygen status of the blood.

Claims

1. A blood analyzing device, which comprises:

a blood gas analyzer;

a conduit comprising a passageway constructed so as to collect and hold blood, said conduit being further formed with an inlet constructed so as to provide blood flow from a patient to said passageway, an outlet and a seating surface defining an aperture therethrough;

an annular-shaped adapter comprising a periphery which defines an opening therethrough, said periphery comprising an outer surface threadably engaged with said conduit and having a threaded inner surface engaged with said analyzer;

a replaceable membrane comprising a first side and a second side, said membrane being removably held between said periphery of said adapter and said seating surface of said conduit to removably cover said aperture with said first side being exposed to said passageway to define part of said passageway and to provide surface contact with the collected blood, said second side of said membrane exposed to contact said analyzer and establish an electrical contact therebetween to analyze the blood in said passageway; and

means engaged with said conduit outlet constructed so as to draw blood from the patient into said passageway through said inlet to bring blood into contact with said first side of said membrane.

2. A blood analyzing device as recited in claim 1 wherein said membrane further comprises a reinforcing ring circumscribing said membrane.

3. A blood analyzing device as recited in claim 1, wherein said passageway is defined by, and continually passes through, said inlet and said outlet.

4. A blood analyzing device as recited in claim 1, wherein said seating surface of said conduit is formed on an inner surface of said conduit, said seating surface being positioned so as to abut said adapter.

5. A method for analyzing blood, which comprises:

(a) engaging a syringe with a blood collecting chamber which comprises an annular shaped adapter defining a periphery, said periphery comprising a threaded inner surface and a threaded outer surface and forming an opening therethrough, a replaceable electrically conductive membrane to removably cover said opening;

a conduit forming said chamber and comprising a fluid passageway therethrough, said conduit further comprising an inlet constructed so as to provide blood flow from a patient to said passageway, an outlet, and a seating surface defining an aperture therethrough, said conduit threadably engaged with the outer surface of said adapter removably holding said membrane between said periphery of said adapter and said seating surface of said conduit to define part of said chamber; and

an electrode electrically connected to a blood gas analyzer, said analyzer having means threadably engaged with the inner surface of said adapter to hold said electrode against said membrane to establish electro-chemical contact with said membrane;

(b) manipulating said syringe to draw blood into said passageway through said inlet; and

(c) energizing said analyzer to analyze the blood in said passageway.

6. A method for analyzing blood as recited in claim 5 wherein said membrane further comprises a reinforcing ring circumscribing said membrane.