JPS586907B2 - Sansokanrenkiyokusenno Sokuteihouhou Oyobi Sonosouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a method and apparatus for measuring the oxygenation properties of blood or other substances whose absorbance properties change during treatment with reagents, and in particular to oxygenation properties of whole blood samples. The present invention relates to a method and apparatus for inducing a conversion curve.

The main purpose of this invention is to determine the degree of oxygenation of a whole blood sample while it is being treated with an oxygenating reagent, in particular to determine the absorbance of a substance that has been treated with a reagent that alters its absorbance. The object of the present invention is to provide a new and improved method and apparatus for doing so.

Another object of the invention is to provide an improved method and apparatus for measuring and recording absorbance changes in a blood sample that has been treated with an oxygenating reagent, said method comprising relatively simple processing steps. and only a small amount of sample is required, and the device is relatively cheap to assemble and easy to operate.

Yet another object of this invention is to provide an improved absorption cell for use in a photometric device for measuring the oxygenation properties of blood or similar substances, wherein the substance is treated with a reagent that alters its absorption properties. There is.

Yet another object of this invention is to provide an improved absorption cell for use in a dual wavelength photometer or similar optical instrument for inducing oxygen-related curves of blood ampoules, the cell being flat, transparent and gas-permeable. arranged to spread a thin layer of sample exposed to an oxygenated gaseous reagent through a porous membrane;
During which optical absorption measurements are performed to determine the proportion of oxygenated hemoglobin in the sample, the arrangement includes means for continuously varying the partial pressure of oxygen surrounding the cell, thereby producing a continuous oxygen-related curve. be able to.

This arrangement allows the use of undiluted whole blood as the sample, avoids the need to use harsh reagents, and
requires only a small amount of sample, obtains a measurement line of the oxyhemoglobin ratio over the entire oxygenation range, obtains a continuous oxygen-related curve by simple and precise control and variation of the oxygen partial pressure,
It uses an oxygen sensing means that requires only small amounts of gaseous reagents, has greater stability and durability, and does not come into direct contact with the blood sample.

Yet another object of this invention is to provide an improved method for measuring and recording absorbance changes in a blood sample being treated with an oxygenating reagent, which method detects the optical response of a blood sample to oxygenation. It involves a new and improved procedure for suitably preconditioning the sample before actual measurement.

Yet another object of the invention is to provide an improved apparatus for supporting a thin, flat layer of a blood sample in the path of a multiwavelength photometer or similar optical instrument for inducing an oxygen-related curve of the blood sample, the support The device is arranged to spread out the sample to form the required thin flat layer to obtain proper exposure of the sample to deoxygenating and oxygenating reagents, and to provide adequate exposure of the sample to deoxygenating and oxygenating reagents, and to Perform an optical absorption measurement to measure the proportion of oxygenated hemoglobin.

This support device has a simple structure and allows for easy insertion and replacement of blood samples.

Other objects and advantages of the invention will become apparent from the following description and claims, as well as from the drawings.

Hemoglobin's oxygen binding curve (generally known as the "oxygen dissociation curve")
) is formed by measuring the proportion of total hemoglobin that is oxygenated as a function of the partial pressure of oxygen (PO2) to which the hemoglobin sample is exposed.

The overall curve and/or the parameters derived therefrom are of substantial physiological and clinical significance.

The methods currently used in this field use dual-wavelength photometers; such methods use a time-shared measurement and reference beam λM,
With these absorbance differences measured by a photomultiplier tube and associated circuitry to pass λR and induce the desired "oxygen dissociation curve", these are effectively oxygen-related curves.

This invention allows a sample consisting of a thin layer of whole blood to be exposed to a controlled PO2 (oxygen partial pressure) through a stretched flat transparent gas-permeable membrane and at the same time to measure the proportion of oxygenated hemoglobin. A method for measuring optical absorption is specified.

PO2 is varied in a controlled manner, it is measured, and a continuous "oxygen dissociation curve" is generated from the observed data.

The method and apparatus of the present invention offer a number of distinct advantages over currently used methods, among them:

1. By allowing the use of undiluted whole blood, possible non-physiological artifacts are avoided.

2. Achieves deoxygenation of blood samples without the use of harsh reagents such as dithionates.

3. Only very small samples are required, which is important in pediatric cases and in rare hemoglobin studies.

4. Unlike reflex measurement methods, it provides a measurement line of the percentage of oxyhemoglobin over the entire range of oxygenation.

5. It provides control and variation of PO2 that produces a continuous curve, yet is uncomplicated, accurate, and requires only a small amount of compressed gas.

6. An oxygen-sensing electrode is used that is inherently stable, has a long lifetime, and does not come into direct contact with the blood sample.

The inventive method involves the use of a sample cell in which a thin layer of blood is exposed to controlled PO2 through a gas permeable membrane and at the same time optical absorption spectroscopy measurements are taken.

Blood with a layer thickness of 0.010 inches or less allows rapid oxygen exchange within the blood and is sufficiently transparent for optical absorption measurements of undiluted blood samples.

This film thickness must be stable for stable optical measurements and must not contain closed cells for optical and gas exchange.

Referring to the drawings, 11 generally indicates an apparatus for inducing oxygen-related curves according to the present invention.

The device 11 consists of a gas chamber 26 made of a suitable opaque material, such as aluminum, which is suitable for installation in the path of the time-shared monochromatic light λM, λR of a two-wavelength spectrophotometer, for example.

In the typical apparatus illustrated in FIG. 1, the gas chamber has at its bottom wall a transparent window 12 through which the time-shared beams λM, λR enter, and at its top wall another transparent window 12 vertically aligned with the window 12. It has a window 13 forming an optical path between them and the emerging light is directed to a photomultiplier tube 42 of the spectrophotometer.

A blood sample cell is indicated generally at 14 and is placed horizontally in the path of the time-resolved monochromatic light λM, λR.

Referring to FIGS. 2 and 3, the cell 14 comprises a generally circular body 15 of a suitable transparent material, such as a transparent plastic material, having a concentric shallow circular recess 16 in its top surface. The recess has a depth of about 0,010 inches and a diameter on the order of 3/8 inch.

Each inlet and outlet capillary 17, 18 is connected to the main body 1
5 and in communication with the diametrically opposed portions of the corresponding recesses 16 .

The body 15 is formed with a rounded rim 43 leading to a circumferential groove 19 which accommodates the edge of the transparent gas permeable membrane 20, which edge encloses the main portion of the membrane over the recess 16. It is strongly stretched and tightly fixed in the groove 19 by the elastic O-ring 21.

Gas permeable membrane 20 is approximately 0.001 inch thick and is made of Perfle silicone rubber copolymer manufactured by Union Carbide Co., Moorestown, NJ.
x Pure silicone rubber, such as OM-110 (trade name), or a suitable commercially available transparent gas permeable membrane.

The body 15 is reduced at its lower part, as indicated at 22, and the reduced lower part is supported and received in a bracket ring 23 with a oriented support arm 24, which arm is fixed to the adjacent side wall 25 of the gas chamber 26. .

The ring 23 includes a set screw 27 diametrically opposed to the arm 24 which tightens and secures the reduced lower portion 22 within the ring 23.

The capillary tubes 17 and 18 extend in a sealed manner through the side wall 25 of the gas chamber 26.

An oxygen supply conduit 28 with a suitable regulating valve 29 connects to the gas chamber 2.
A nitrogen supply conduit 31 extending sealingly through the opposite side wall 30 of 6 and equipped with a suitable regulating valve 32 extends sealingly through the side wall 30 .

A shaft 33 of the fan 34 is rotatably and substantially hermetically supported on the side wall 30, and the shaft is connected to the external electric motor 3.
5 as appropriate.

A well-known oxygen sensing electrode 36 is hermetically mounted in the side wall 30 and extends into the gas chamber, the electrode being externally connected to suitable circuit means for generating the X component of the well-known X-Y recorder.

Oxygen sensing electrode 36 may be similar to a model 5331 of the type known as the "Clark Electrode" manufactured by Yellow Springs Instruments Inc. (Yellow Springs, Ohio).

A water-absorbing humidifying member 46 that can be easily moistened is installed in the lower part of the gas chamber 26, for example in a recess provided in the lower part of the side wall 25.

The spacing member 46 provides the necessary humidity to prevent the oxygen electrode 36 and blood sample from drying out excessively.

The gas chamber 26 is temperature controlled to maintain a substantially constant temperature by an electric heater 37 secured in heat transfer relation to the gas chamber, the excitation of which is applied to the gas chamber adjacent to the heater. Adjustment is made in a conventional manner by means of an embedded temperature sensing element 40.

A limited vent passage 41 is provided at the top of the side wall 25.

In a typical embodiment, the gas chamber wall thickness was about 0.6 inches and the vent passageway 41 was about 0.025 inches in diameter.

In a combined dual wavelength spectrophotometer, various wavelength pairs such as 650nm-800nm1 547nm-560nm
m or 650nm-724nm may be used for λM and λR monochromatic light.

The advantages of using a dual-wavelength system for measurements include, along with the generation of the oxygen-related curve, at the same time (a) automatically correcting for any changes in the scattered light during the generation of the test curve; (b) passing through the sample as well. (C) the possibility of the ability to measure hematocrit or other parameters;

A single wavelength measurement system may be used with the gas chamber and blood cell devices of the invention, resulting in lower cost and simpler construction, but does not automatically account for possible changes in the scattered light during the generation of the oxygen-related curve. cannot be corrected.

In operation, membrane cell 14 is supplied with a whole blood sample admitted through inlet capillary 17 .

Gas chamber 26 is first filled with N2 (containing about 5% CO2) via conduit 31 by opening valve 32, thereby deoxygenating the blood sample.

Initial deoxygenation of this sample requires approximately 15 minutes of exposure.

Then, by closing valve 32 and operating the spectrophotometer, the oxygen binding curve (oxygen related curve) is adjusted by operating valve 29 to gradually introduce O2 (containing about 5% CO2). Generated on the connected X-Y recorder.

The oxygen supply system will supply oxygen 2 in the gas chamber in 5 to 10 minutes.
You may have a syringe pump or other pump to obtain sufficient oxygen input ratio to achieve 0%.

Since the change in PO2 over time is exponential rather than linear, the oxygen binding curve is preferably created using an X-Y recorder, with oxygen electrode 36 driving the X-axis and photomultiplier tube 42, It is generated by generating a signal for generating the Y component in the Y component.

Since the oxygen electrode 35 is not in contact with the blood sample, the change in the gas chamber must be slow enough so that the blood is always in practical equilibrium with PO2.

The size of the fan 34 is selected to obtain homogeneous and intense mixing during the course of the test.

A 0.010 inch blood layer within cell 14 will be reduced to 5 to 10 inches by initial deoxygenation, which takes approximately 15 minutes as described above.
Allows controlled oxygenation of blood in minutes.

By using a thinner blood layer (eg, 0.004 inches or less), the required exposure time can be correspondingly reduced.

Placing the cell 14 horizontally, as described above, eliminates the difficulties that can arise associated with sedimentation of red blood cells during long-term experiments.

Blood samples are pretreated with suitable reagents such as heparin or other known anticoagulants to prevent clotting.

This is done when blood is drawn from the patient.

4 and 5 illustrate other embodiments of the membrane cell described generally at 14 in accordance with the present invention.

Cell 14' consists of a stainless steel ring 15' forming an annular internal seat 50 to which is joined a circular quartz window 51 whose top surface is approximately 0.010 inches below the top surface of the ring to accommodate the primary blood sample. Form a depression.

Diametrically opposed channel recesses 52,53 are formed in the top of the ring and communicate with said main recess.

Capillaries 17, 18 extend vertically and sealingly through opposite parts of ring 15 and communicate with channel recesses 52, 53.

This ring has a reduced lower part 22 which is clamped onto a support ring 23, similar to that already described in FIGS. 2 and 3.

The ring 15' has a rounded rim portion 43 leading to the circumferential groove 19'.
A transparent, gas-permeable membrane 20 with an extended and stretched membrane 20 is secured over the blood sample well by an O-ring 21, which, like the cell 14 previously described, holds the edge of the membrane in the groove 19'. .

Various means other than using an O-ring may be used to secure the stretched transparent gas permeable membrane over the blood sample well.

Thus, for example, the membrane may be clamped with suitable jig members.

A film of silicone rubber cement is applied to the rim of the main cell body, and the rim is tightened firmly against the membrane and held until the cement hardens, after which excess membrane material is removed. You can cut it out.

Although the procedure described above uses whole blood as the sample, it is also possible to use diluted blood or hemoglobin solution as the sample in the procedure.

In some cases, it is possible to omit the coating 20 and simply use a thin blood layer on the order of 0.001 inch thick on a flat transparent support plate, which plate has a gas chamber in place of the cell 14. 26 as appropriate.

Under these conditions it is necessary to carefully regulate the humidity in the gas chamber.

In the embodiment illustrated in FIGS. 6-10, the gas chamber designated 26' is provided with a large circular hole 60 in its right end wall 25', as shown in FIG.

The vertical cover plate 61 is slidably supported by a pair of horizontally parallel and relatively long support rod members 62, which are each screwed and fixed to a lower corner of the end wall 25'. ing.

The rod members 62, 62 are provided with outer heads 63, 6 in order to limit the right side drawer of the cover plate 61 to the dotted line portion in FIG.
It has 3.

Cover plate 61 is formed with an inwardly projecting integral circular boss 64 which is shaped to substantially fit within bore 60 in the cover plate's closed position.

The support rod members 62, 62 have an annular fastening groove 6 at their inner ends.
5, and the bottom end of the cover plate 61 is provided with a locking ball 66 with a spring eccentric projecting into the groove 65 and lockable, so that the cover plate 61 is in the closed position shown in solid lines in FIG.
hold.

The cover plate 61 is provided with a central operating knob 67 on the outside.

The horizontal support arm 24' is fixed to the central portion of the boss 64;
The arm holds a blood sample cell element shown at 68.

The support cell element 68 consists of an opaque element, which is essentially annular, having a bottom central hole 69 and an upright circumferential flange 70 having separate cutouts 71, 71 as shown in FIG. Forms a finger entry and exit point for removing such samples.

As will be described below, a blood sample is supported on a circular transparent disk 72, such as glass, placed in a position defined by element 68, and a blood sample shown at 74 (see FIG. 10) is placed on top of the sample. It is covered by a gas permeable membrane disk 73 which is held in place by the surface tension of.

The dual-wavelength optical system used may be similar to that previously described, but a more economical system that can be used consists of a suitable polychromatic light source 75 containing a reference wavelength λR and a measurement wavelength λM, with a bottom window 12, The aperture 69 is arranged to form a light beam 76 directed upwardly through the blood sample 74 between the discs 72, 73 and the top window 13.

After absorption by the blood sample, light 76 passes from the top 13 to a light splitter 77, such as a half-silvered 45° mirror, forming two outgoing light beams 78,79.

Beam 78 is transmitted through a half silver plated mirror and beam 79 is reflected therefrom.

Beam 78 is passed from a suitable λR filter 80 to first photocell 8
1 and the beam 79 is passed through an appropriate λM filter 8.
2' to the second photocell 82.

The output currents λR and IλM of the phototubes 81 and 82 are applied to each input of a well-known arithmetic logarithmic amplifier 83, and logIλM−
Provides an output signal equal to log λR or logIλM/IλR.

The output signal of amplifier 83 is transmitted to the Y input of the connected X-Y recorder.

As in the previously described embodiments of the invention, an oxygen sensing electrode is placed within the gas chamber 26' to generate the X component of the recorder.

In the typical arrangement of FIGS. 7-10, the glass disk 72 has a diameter of about 18 mm and the transparent membrane disk is about 10 mm.

The support cell element 68 is shaped to be suitable for accommodating a disk 72, as shown in FIGS. From there, when it is desired to remove the disk 72, the part can be easily grasped between the operator's fingers and the blood sample 74 can be removed from the holder or element 68 (at the cover plate 61 in the dotted position in FIG. 7). It can be seen that the membrane disc 73 can also be removed.

The blood sample layer to be tested is prepared as follows.

Place the disc 72 onto the holder or element 68.

A drop of blood with a volume of 1-2 microliters is placed in the center of the disk 72.

Membrane Disc 73 (General, manufactured by General Electric Co., Schenectaday, New York;
An electric disk (such as M-EM-213 material) is placed over the blood sample and a thin layer 74 is formed by the weight of the disk and capillary action.

Thereafter, the cover plate 61 is moved to the closed position shown in solid lines in FIG.

The blood layer has a thickness of less than 25 microns, with a thickness of 10-2
It may be as thin as 0 micron.

This allows complete deoxygenation in 1.5-2 minutes, rapid one-step oxygenation in 3-5 seconds, and generation of equilibrium oxygen-related curves in about 5 minutes.

In contrast, a 0.01 inch thick blood layer requires 15-20 minutes for deoxygenation and 30-50 seconds for rapid one-step oxygenation.

The use of a gas permeable non-porous membrane disc 73 also slows water loss and allows safe disposal of blood layers in ambient air.

Suitable wavelengths for dual wavelength spectrophotometers using blood layers less than 25 microns thick are 438 nm and 448 nm, and therefore these wavelengths are preferably used for λM and λR.

For a sample to be placed in a holder or element 68 as described above, it is first precirculated for accurate blood regulation (a very important requirement) as follows.

Nitrogen containing 5% CO2 is rapidly blown into the gas chamber 26' at a rate of 100 cc/min for about 1 minute, for example, to deoxygenate the sample.

The sample is then heated to CO25 at about 120 mm pressure for about 5 seconds.
It is quickly oxygenated by adding oxygen containing %.

The X-Y recorder is then modified by adjusting so the optical signal sets the stored Y component reading to indicate 100% oxygenation.

The gas chamber 26' is then purged with nitrogen containing 5% CO2.

After deoxygenation, the optical signal is read again and the oxygenation O%
is stored as.

2 storage values are used to set zero deviation and scale stretch on the Y component of the X-Y recorder, so the graph automatically spans 0-100% of the Y axis.

The oxygen-related curve of the sample was obtained by continuing the procedure already described, i.e. by introducing oxygen into the gas chamber and
It may be generated by measuring the change in logIλM/IλR versus oxygen concentration using the optical system described above in conjunction with a Y recorder.

This allows measuring the ratio change in optical density corresponding to the proportion of oxyhemoglobin in the sample over a range of oxygen concentrations in the gas chamber 26'.

The method described here creates a blood layer that is relatively evaporative and quite stable over time, so that, for example, repeated related curve measurements can be performed on the same sample.

As can be seen, when removing a sample from the gas chamber 26', the cover plate 61 is pulled open to its extended position and the operator grasps the protruding opposite end of the disc 72 between his fingers to remove the disc. The sample can be easily removed by lifting it from the holder or element 68.

Although certain exemplary improved methods and apparatus for generating oxygen-related curves for blood samples have been described above, it should be understood that various modifications will occur to those skilled in the art that are within the spirit of the invention.

Therefore, the invention is not limited except by the scope of the claims.

Next, embodiments of this invention will be listed.

1. 3. The cell means comprises a light transmitting body having a shallow, flat sample-receiving recess, and a transparent gas-permeable membrane fixed on the body and covering the recess.
The device described in.

2. 4. The apparatus according to claim 3, further comprising oxygen sensing means installed in the gas chamber.

3. 2. The device according to item 2, wherein the oxygen sensing means is an oxygen electrode.

4. 12. The cell means comprises a light transmitting body having a shallow, planar sample receiving recess approximately 0.010 inches deep, and a transparent gas permeable membrane affixed onto the body and covering the recess. 3. The device according to 3.

5. 5. The device according to claim 4, comprising an oxygen sensing electrode installed in the gas chamber.

6. 4. The apparatus of claim 3, wherein the gas chamber has a limited gas vent passage in its wall.

7. The cell means comprises a light transmitting body, a transparent support element disposed on the light transmitting body and arranged to contain a sample material, and a transparent gas permeable membrane suitable for overlaying the sample material. Claim 3 consisting of a member
The device described in.

8. 8. Apparatus according to claim 7, wherein the light transmitting body is formed with fixed seat means shaped to accommodate a transparent support element.

9. 9. Apparatus according to claim 8, wherein said transparent support elements project from opposite sides of said sheet means.

10. 4. Apparatus according to claim 3, wherein the gas chamber comprises a retractable closure member, and the light transmission body is supportingly connected to the closure member.

11. 11. Apparatus according to claim 10, wherein the closure member comprises a vertical plate and the gas chamber comprises means for slidably supporting the plate for horizontal withdrawal with respect to the chamber.

12. The means for comparing the relative absorbance with the amount of oxygen that has entered the gas chamber includes means for generating a first electrical signal based on the relative absorbance, means for generating a second electrical signal based on the amount of oxygen that has entered the gas chamber, and means for generating a second electrical signal based on the amount of oxygen that has entered the gas chamber. 5. The apparatus of claim 4, further comprising means for plotting said first signal against two signals.

13. 6. The device of claim 5, wherein the recess has a depth on the order of 0.010 inches to support a thin flat layer of blood within the recess.

14. 5. The apparatus of claim 4, wherein the body includes a constriction and an annular support bracket member supporting, receiving and surrounding the constriction.

15. Claim 1: The deoxygenating gas is nitrogen.
The method described in.

16. 2. The method of claim 1, wherein the measured absorbance change is continuously plotted against the amount of oxygen to which the flat layer is exposed, thereby generating an oxygen-related curve for the blood sample.

17. 2. The method of claim 1, wherein the flat layer of blood sample is exposed to a deoxygenated gas and to a controlled ratio of oxygen through a gas permeable membrane.

18. deoxygenating a blood sample by placing it in a thin flat configuration and exposing the sample to a deoxygenating gas; then exposing the deoxygenated flat layer of the blood sample to oxygen; using one wavelength with substantially no absorbance change between oxygenated and deoxygenated blood and another wavelength with a relatively large absorbance change between oxygenated and deoxygenated blood. Passing illumination light comprising two wavelengths through the sample while the sample is oxygenated, and plotting the fraction of the equivalent absorption of the two wavelengths versus the amount of oxygen when the sample is oxygenated. How to generate oxygen-related curves.

19. 19. The method of claim 18, wherein the flat layer of blood sample is conditioned by first being exposed to a deoxygenated gas and then exposed to an oxygenated gas.

20. 19. The method of claim 18, wherein the thin planar layer places the sample between a pair of transparent members and causes the sample to spread between the transparent members by capillary action.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional view of a typical blood sample oxygenation-related device constructed in the present invention; FIG. 2 is a sample cell used in the device taken substantially along line 2--2 of FIG. FIG. 3 is a vertical sectional view taken substantially along the line 3--3 of FIG. 2, and FIG. 4 is a modified example of the sample cell according to the present invention. 5 is a vertical cross-sectional view taken substantially along line 5--5 of FIG. 4; FIG. 6 is another variation of a blood sample oxygenation-related device according to the invention; FIG. An end view of the example, FIG. 7, is a vertical cross-sectional view taken substantially along line 7--7 of FIG. 6 and schematically illustrates associated optical and electrical components for use with a variation of the invention, FIG. is substantially 8-8 in Figure 7.
A plan view of the blood sample support member for use in the variations of FIGS. 6 and 7 along the lines, FIG.
FIG. 10 is a partially enlarged vertical cross-sectional view taken substantially along line 10--10 of FIG. 8; 11... Oxygen-related curve generation device, 12, 13.
... Window, 14 ... Blood sample cell, 15 ... 1 ... Cell body, 16 ... Circular recess, 17, 18 ... Capillary tube, 19...
...Circumferential groove, 20...Gas permeable membrane, 21...
... 0 ring, 22 ... Reduced lower part of cell body, 23 ... Bracket ring, 24 ...
... Center facing support arm, 25 ... Side wall, 26.
...Gas chamber, 27... Set screw, 28.
...Oxygen supply conduit, 29 ...Adjustment valve, 3
0... Side wall, 31... Nitrogen supply conduit,
32...Adjusting valve, 33...Shaft,
34... Fan, 35... Electric motor, 36... Oxygen sensing electrode, 37... Electric heater, 40... Temperature sensing element , 41...
...Vent passage, 42...Photomultiplier tube, 46
・・・・・・Humidification part.

Claims (1)

Claims: 1. Deoxygenating a blood sample by first placing it in a thin flat layer and exposing the sample to a deoxygenating gas, and then oxygenating the deoxygenated flat layer of the blood sample at a controlled rate. and measuring the change in absorbance of the flat layer while the flat layer is exposed to oxygen at the controlled rate. 2 deoxygenating the blood sample by placing it in a thin flat layer and first exposing the sample to a deoxygenating gas, exposing the deoxygenated flat layer of the blood sample to oxygen;
The amount of oxygen to which the sample is exposed is continuously measured, with absorbance at one wavelength that does not substantially change between oxygenated and deoxygenated blood and is relatively large between oxygenated and deoxygenated blood. passing two wavelengths of monochromatic light through the sample while the sample is oxygenated, using another wavelength with an absorbance change, and measuring the two wavelengths relative to the amount of oxygen while the sample is oxygenated. A method for measuring an oxygen-related curve characterized by plotting an absorption difference. 3 a gas chamber, means for transmitting a measurement light beam into the gas chamber, light transmission cell means arranged to support a thin planar layer of sample material within the gas chamber in the optical path of the measurement light beam; a deoxygenated gas source, control conduit means connecting the deoxygenated gas source to a gas chamber, an oxygen source, and control conduit means connecting the oxygen source to the gas chamber,
Attached device for oxygen-related curve measurement photometer. 4. a light source for generating measurement light and means for comparing the relative absorbance of two wavelengths together with the amount of oxygen that has entered the gas chamber, said light source comprising at least two wavelengths, said wavelengths passing through the blood sample undergoing oxygenation. 4. A device according to claim 3, having different absorption characteristics when transmitted. 5. a light transmitting support body formed with a shallow recess, a transparent means for supporting a blood sample on the body within the recess, and a transparent support body suitable for stacking the blood sample on the support means; 1. A sample device for measuring a hemoglobin oxygen-related curve, comprising: a gas permeable membrane;