Extracorporeal blood gas exchange device

Abstract

An extracorporeal blood gas exchange device has a bloodstream area for guiding a bloodstream, a gas-carrying area for guiding a gas flow, and a membrane, which forms a gas-liquid barrier between the bloodstream and the gas flow, and which further makes possible the transfer of carbon dioxide of the bloodstream into the gas flow. The device further has at least one measuring cuvette, which is separated from the bloodstream area at least partially by the membrane, so that carbon dioxide of the bloodstream can pass over into the measuring cuvette. The device has an optical measuring unit, which is configured to measure a carbon dioxide partial pressure present in the measuring cuvette.

Claims

1. An extracorporeal blood gas exchange device comprising: a bloodstream area for guiding a bloodstream; a housing comprising a gas-carrying area for guiding a gas flow; a membrane, which forms a gas-liquid barrier between the bloodstream and the gas flow and which further makes possible a transfer of carbon dioxide of the bloodstream into the gas flow; at least one measuring cuvette, which is separated from the bloodstream area by the membrane at least partially, so that carbon dioxide of the bloodstream can pass over into the measuring cuvette; and an optical measuring unit, which is configured to measure a carbon dioxide partial pressure present in the measuring cuvette, the optical measuring unit being free of contact with the gas flow in the gas-carrying area.

2. A device in accordance with claim 1, wherein the measuring cuvette comprises a cuvette wall providing a gas-tight closure against the gas-carrying area.

3. A device in accordance with claim 2, wherein the cuvette wall separates the optical measuring unit from the gas-carrying area and the gas flow in the gas-carrying area.

4. A device in accordance with claim 1, wherein the optical measuring unit is configured to emit optical radiation into the measuring cuvette and to detect a portion of the optical radiation transmitted though the measuring cuvette.

5. A device in accordance with claim 4, wherein the optical radiation is an infrared radiation.

6. A device in accordance with claim 4, wherein the measuring cuvette comprises: a first optical window for admitting the optical radiation into the measuring cuvette; and a second optical window for allowing the optical radiation to exit from the measuring cuvette.

7. A device in accordance with claim 1, wherein: the device has an inflow side, on which the bloodstream flows into the device, as well as an outflow side, on which the bloodstream flows out of the device; and the measuring cuvette is located at or adjacent to a location of the membrane that corresponds to the inflow side.

8. A device in accordance with claim 1, wherein: the device has an inflow side, on which the bloodstream flows into the device, as well as an outflow side, on which the bloodstream flows out of the device, and the measuring cuvette is located at or adjacent to a location of the membrane that corresponds to the outflow side.

9. A device in accordance with claim 1, wherein the membrane is formed by a plurality of hollow fiber arrays.

10. A device in accordance with claim 9, wherein: the device has an inflow side, on which the bloodstream flows into the device, as well as an outflow side, on which the bloodstream flows out of the device; and the measuring cuvette is formed by a hollow fiber array, which is located adjacent to the inflow side.

11. A device in accordance with claim 9, wherein: the device has an inflow side, on which the bloodstream flows into the device, as well as an outflow side, on which the bloodstream flows out of the device; and the measuring cuvette is formed by such a hollow fiber array, which is located close to the outflow side.

12. An extracorporeal blood gas exchange device comprising: a bloodstream area for guiding a bloodstream; a housing comprising a gas-carrying area for guiding a gas flow; a membrane, which forms a gas-liquid barrier between the bloodstream and the gas flow and which further makes possible a transfer of carbon dioxide of the bloodstream into the gas flow; at least one measuring cuvette, which is separated from the bloodstream area by the membrane at least partially, so that carbon dioxide of the bloodstream can pass over into the measuring cuvette; and an optical measuring unit, which is configured to measure a carbon dioxide partial pressure present in the measuring cuvette, the optical measuring unit being located at a position outside of the gas flow in the gas-carrying area.

13. A device in accordance with claim 12, wherein the measuring cuvette comprises a cuvette wall providing a gas-tight closure space against the gas-carrying area, wherein at least a portion of the optical measuring unit is located in the gas-tight closure space.

14. A device in accordance with claim 12, wherein the measuring cuvette comprises a cuvette wall providing a gas-tight closure against the gas-carrying area.

15. A device in accordance with claim 14, wherein the cuvette wall separates the optical measuring unit from the gas-carrying area and the gas flow in the gas-carrying area.

16. A device in accordance with claim 12, wherein the optical measuring unit is not in contact with the gas flow in the gas-carrying area.

17. An extracorporeal blood gas exchange device comprising: a bloodstream area for guiding a bloodstream; a housing comprising a gas-carrying area for guiding a gas flow; a membrane, which forms a gas-liquid barrier between the bloodstream and the gas flow and which further makes possible a transfer of carbon dioxide of the bloodstream into the gas flow; at least one measuring cuvette, which is separated from the bloodstream area by the membrane at least partially, so that carbon dioxide of the bloodstream can pass over into the measuring cuvette; and an optical measuring unit, which is configured to measure a carbon dioxide partial pressure present in the measuring cuvette, the optical measuring unit being located at a spaced location from the gas flow in the gas-carrying area.

18. A device in accordance with claim 17, wherein the measuring cuvette comprises a cuvette wall providing a gas-tight closure space against the gas-carrying area, wherein at least a portion of the optical measuring unit is located in the gas-tight closure space.

19. A device in accordance with claim 17, wherein the measuring cuvette comprises a cuvette wall providing a gas-tight closure against the gas-carrying area, the cuvette wall separating the optical measuring unit from the gas-carrying area and the gas flow in the gas-carrying area.

20. A device in accordance with claim 17, wherein the optical measuring unit is not in contact with the gas flow in the gas-carrying area.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1 is a schematic view of a preferred embodiment of the extracorporeal blood gas exchange device according to the present invention;

(3) FIG. 2a is a schematic view showing details of a preferred embodiment of a measuring cuvette;

(4) FIG. 2b is a schematic view showing a preferred embodiment of a measuring unit; and

(5) FIG. 3 is a schematic view of another preferred embodiment of the extracorporeal blood gas exchange device according to the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

(6) Referring to the drawings, FIG. 1 shows the extracorporeal blood gas exchange device V.

(7) A bloodstream BS flows through an inflow area ES in a bloodstream area BB along a membrane M and finally to the outflow area AS.

(8) As a gas-liquid barrier, the membrane M separates the bloodstream area BB from a gas-carrying area GB, which carries a gas flow GS.

(9) A portion of carbon dioxide K can pass over through the membrane from the bloodstream BS into the gas flow as well as a portion of oxygen S can pass over from the gas flow GS into the bloodstream BS.

(10) A measuring cuvette MK2 is separated by the membrane M from the bloodstream area BB. Carbon dioxide K can also now pass over from the bloodstream BS into the cuvette MK2.

(11) An optical measuring unit ME can now measure a carbon dioxide partial pressure present in the measuring cuvette MK2.

(12) The measuring cuvette MK2 is closed by a cuvette wall KW providing a gas-tight closure against the gas-carrying area GB (closed in a gas-tight manner).

(13) While the bloodstream BS is flowing into the device V on the inflow side ES, the bloodstream BS then flows out of the device V on the outflow side AS.

(14) The measuring cuvette MK2 is located at a point of the membrane M that corresponds to the outflow side AS.

(15) As a result, such a portion of carbon dioxide that corresponds to the portion of carbon dioxide of the bloodstream BS after depletion through the membrane M can be measured by the measuring unit ME at the measuring cuvette MK2. As a result, information can now consequently advantageously be obtained on the carbon dioxide partial pressure present in the bloodstream BS when the bloodstream BS leaves the device V on the outflow side AS.

(16) As an alternative or in addition, a measuring cuvette MK1, which is configured analogously to the measuring cuvette MK2 and are located at such a point of the membrane M that corresponds to the inflow side ES, may be present.

(17) FIG. 2a shows details of an embodiment of the measuring cuvette MK1 as an embodiment MK11. It should be noted that the measuring cuvette MK2 from FIG. 1 may likewise have a configuration analogous to that of the measuring cuvette MK11 shown in FIG. 2a.

(18) The measuring cuvette MK11 in this embodiment has an optical window OF1, via which an optical radiation can be admitted into the measuring cuvette.

(19) The measuring cuvette MK11 further has an optical window OF2, which is suitable for allowing an optical radiation to exit the measuring cuvette MK11.

(20) FIG. 2b shows for this the measuring unit ME, which was mentioned before with reference to FIG. 1.

(21) The measuring unit ME is configured to emit optical radiation OS into the measuring cuvette MK11 and to detect a portion of the optical radiation OS transmitted through the measuring cuvette MK11.

(22) The measuring unit ME has for this an optical emitter E, which is positioned correspondingly in front of the optical window OF1.

(23) The measuring unit ME further has one or more detectors D1, D2, by which corresponding wavelengths of the optical radiation OS transmitted through the measuring cuvette MK11 can be detected behind the optical window OF2.

(24) The emitter E and the detectors D1, D2 are in connection here with a corresponding control unit or computer SE of the measuring unit ME.

(25) Different wavelengths are preferably detected by the detectors D1, D2. Principles of the optical measurement of partial gas pressures and partial gas concentration on the basis of at least two different optical wavelengths are known to the person skilled in the art, for example, from the German patent application with application number 102015008323.6.

(26) FIG. 3 shows another preferred embodiment of an extracorporeal blood gas exchange device V2 according to the present invention.

(27) The bloodstream BS flows in via an inflow side ES2 and flows out via an outflow side AS2.

(28) The bloodstream area BB2 is separated here from a gas-carrying area GB2 due to the corresponding membrane M being formed by a plurality of hollow fiber arrays HA1, HA2. Each of such hollow fiber arrays preferably has a plurality of hollow fibers HF.

(29) Such hollow fiber arrays HA1, HA2 may also be in the form of corresponding hollow fiber mats. A hollow fiber mat is preferably an array in which a hollow fiber array of the type of the hollow fiber array HA1 is arranged crossed at right angles with a hollow fiber array of the type of the hollow fiber array HA1, which is rotated by 90°. Analogous statements can be made concerning a hollow fiber mat obtained by forming a plurality of hollow fiber array of the type of the hollow fiber array HA2.

(30) Such a hollow fiber mat then defines a plane, through which the bloodstream BS flows through the hollow fiber mat at right angles to the plane.

(31) The gas flow GS then flows through corresponding hollow fibers HF and the above-described blood gas exchange takes place in the process through the membrane material M.

(32) On the outflow side, i.e., in the vicinity of the outflow side AS2, hollow fibers HF of the outflow-side hollow fiber array HA2 are combined and bundled, so that an area of a measuring cuvette MK12 is formed thereby. Above the outflow side, i.e., the blood outlet opening, the corresponding hollow fibers HF of the outflow-side hollow fiber arrays HA2 are preferably closed by a chamber wall KW2 at the fiber ends FE. It can be achieved thereby that the measurement result will not be distorted by the not yet fully depleted blood in the upper area of the bloodstream area BB2.

(33) A corresponding measuring unit ME, which carries out an optical measurement via corresponding optical windows of the cuvette MK12 according to the principle that was explained above in reference to FIG. 2b, is now located at the measuring cuvette MK12.

(34) According to FIG. 3, the measuring cuvette MK12 is formed by a hollow fiber array HA2, which is located adjacent to the inflow side.

(35) It is obvious to a person skilled in the art that it is equally possible to configure a corresponding measuring cuvette analogously to the measuring cuvette MK12, which is located adjacent to the inflow side ES2.

(36) While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.