METHOD OF REMOVING BLOOD FROM AN EXTRACORPOREAL BLOOD CIRCUIT, TREATMENT APPARATUS, AND TUBE SYSTEM

Abstract

The present invention relates to a method of removing blood from an extracorporeal blood circuit following termination of a blood treatment session, wherein blood is concurrently removed both from an arterial conduit portion and from a venous conduit portion of the extracorporeal blood circuit. It further relates to a method for recognizing and/or eliminating air inclusions in or from an extracorporeal blood circuit and a treatment apparatus as well as a tube system.

Claims

1. A method of removing blood from an extracorporeal blood circuit of a treatment apparatus following termination of a blood treatment session, said method comprising: providing a treatment apparatus for the extracorporeal blood treatment of a patient comprising: an extracorporeal blood circuit, including an arterial conduit portion having a conduit interior and a venous conduit portion having a conduit interior; at least one blood pump for conveying blood within the extracorporeal blood circuit; at least one second conveying means for introducing at least one substituate liquid into the extracorporeal blood circuit and/or for conveying the substituate liquid within the extracorporeal blood circuit; introducing substituate liquid into the extracorporeal blood circuit; and conveying substituate liquid for concurrently discharging blood both from the arterial conduit portion and from the venous conduit portion of the extracorporeal blood circuit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0123] In the following, the present invention shall be described by way of preferred embodiments thereof while making reference to the drawings. In the drawings, identical reference numerals designate same or identical elements, wherein:

[0124] FIG. 1 shows a schematic overview of an exemplary treatment apparatus of the invention for performing the method of the invention.

[0125] FIG. 2 shows in a schematically simplified manner a phase during the performance of a method of the invention.

[0126] FIG. 3 shows a schematic diagram of an extracorporeal blood system including an arterial ABD (air bubble detector).

DETAILED DESCRIPTION OF THE DRAWINGS

[0127] For the exemplary explanation of the present invention a blood treatment apparatus, for example a hemodialyzing apparatus, is selected as a treatment apparatus, and a blood treatment method, for example a hemodialysis, is selected as a method. It is expressly noted that emptying the extracorporeal blood circuit may also take place in accordance with the invention without the removed blood being recirculated to the patient.

[0128] The standard arrows in FIG. 2 indicate a direction of the blood stream. The block arrows each indicate one direction of the substituate stream.

[0129] In FIG. 1 an extracorporeal blood circuit 1000 of a treatment apparatus 2000 of the invention having a double-needle access to the vascular system of a patient 3000 is represented. The extracorporeal blood circuit 1000 comprises an arterial conduit portion 1 as well as a venous conduit portion 3.

[0130] The arterial conduit portion 1 is connected via an arterial patient access, for example as shown in FIG. 1 and having the form of an arterial connection needle 5, to the vascular system of the patient 3000. The venous conduit portion 3 is connected via a venous patient access, for example as shown in FIG. 1 and having the form of a venous connection needle 7, to the vascular system of the patient 3000.

[0131] The arterial conduit portion 1 comprises an arterial patient tube clamp 9; the venous conduit portion 3 comprises a venous patient tube clamp 11. In FIG. 1 both the arterial patient tube clamp 9 and the venous patient tube clamp 11 are represented in an opened, or open, state.

[0132] The extracorporeal blood circuit 1000 comprises a blood pump 13. The blood pump 13 is exemplarily configured as a roller pump. The blood pump 13 conveys blood of the patient 3000 through the extracorporeal blood circuit 1000.

[0133] The extracorporeal blood circuit 1000 comprises a blood treatment means 15, for example a hemodialyzer.

[0134] As is shown in FIG. 1, an arterial pressure sensor 17 is arranged in the arterial conduit portion 1 downstream (relative to the conveying direction that is usual during a blood treatment) from the blood pump 13. In the venous conduit portion 3 a venous drip chamber 19 and a venous pressure sensor 21 upstream from the venous drip chamber 19 are arranged.

[0135] By means of a second conveying means, for example a substituate pump 23, substituate liquid may be introduced into the extracorporeal blood circuit 1000 from a substituate liquid supply means 25 via a substituate liquid feed conduit 27 at a pre-dilution addition site 29 for substituate liquid and/or a post-dilution addition site 31 for substituate liquid. The substituate pump 23 is here exemplarily configured as a roller pump.

[0136] The treatment apparatus 2000 comprises a regulating or control means 33. The control means 33 is connected via a control line 35 to the blood pump 13 and via a control line 37 to the substituate pump 23. It may, however, be sufficient to provide only one regulating or control line, optionally to the blood pump 13 or to the substituate pump 23, in order to perform the method of the invention.

[0137] The control means 33 may, for example, control a conveying rate or a conveying capacity of the blood pump 13 as a function of operating parameters of the substituate pump 23, e.g., the conveying rate or conveying capacity thereof. The control lines 35 and 37 may admit a bidirectional communication between the control means 33 and the blood pump 13 or the substituate pump 23, respectively.

[0138] FIG. 1 shows a connection of the blood treatment apparatus 2000 of the invention to the patient's vascular system. Such a connection is, however, not indispensable for realizing the blood treatment apparatus of the invention but only represents a particular realization and a preferred utilization.

[0139] In FIG. 2 the treatment apparatus 2000 comprises an external functional means such as, for example, a blood cassette 4000. The blood cassette 4000 may be a blood cassette as disclosed in the German Patent Application No. 10 2009 018 664.6 and German Patent Application No. 10 2009 024 468.9. each having the title Externe Funktionseinrichtung, Blutbehandlungsvorrichtung zum Aufnehmen einer erfindungsgem??en externen Funktionseinrichtung, sowie Verfahren [External functional means, blood treatment apparatus for receiving an external functional means in accordance with the invention, and method] that were deposited by the applicant of the present invention with the German Patent and Trademark Office on Apr. 23, 2009 and on Jun. 10, 2009, see above; the respective disclosures of which are herewith in turn fully incorporated by way of reference.

[0140] FIG. 2 shows a phase of a method of the invention for removing blood from the extracorporeal blood circuit 1000 following termination of a blood treatment in a particular embodiment in which the blood is recirculated into the patient's vascular system. Both the arterial patient tube clamp 9 and also the venous patient tube clamp 11 are in an opened, or open, state.

[0141] The blood pump 13 and the substituate pump 23 are operated. In the following, the expressions clockwise or counter-clockwise refer to the plane of drawing of FIG. 2. They are intended to indicate the conveying direction of the pumps during a dialysis treatment and during the method of the invention: During a blood treatment process, the blood pump 13 and the substituate pump 23 usually convey in a counter-clockwise direction as might be seen from FIG. 2.

[0142] During the performance of the method of the invention, the blood pump 13 rotates in the clockwise direction and thus against the conveying direction that is usual during a blood treatment (patientarterial conduit portionblood treatment meansvenous conduit portionpatient).

[0143] The substituate pump 23 rotates in the counter-clockwise direction.

[0144] The rotational speeds of the blood pump 13 and of the substituate pump 23 may be different from each other. The rotation speeds of blood pump 13 and substituate pump 23 may be identical. The blood pump 13 and the substituate pump 23 may be started at a same point of time and/or made to rotate for a same (predetermined) time period. The blood pump 13 and the substituate pump 23 may be made to rotate at different points of time and/or for different (predetermined) time periods.

[0145] Blood is present in the extracorporeal blood circuit 1000 (simple-hatching area). Substituate liquid is introduced via the substituate liquid feed conduit 27 (cross-hatched area in FIG. 2).

[0146] A pre-dilution addition valve 291 of the pre-dilution addition site 29 is opened. As an alternative, or in addition, a post-dilution addition valve 311 of the post-dilution addition site 31 may also be opened. In the representation shown in FIG. 2, the post-dilution addition valve 311 of the post-dilution addition site 31 is, however, closed.

[0147] The pre-dilution addition valve 291 and the post-dilution addition valve 311 may, for example, be configured as so-called phantom valves as disclosed in the above-mentioned applications to the present applicant having the title Externe Funktionseinrichtung, Blutbehandlungsvorrichtung zum Aufnehmen einer erfindungsgem??en externen Funktionseinrichtung, sowie Verfahren [External functional means, blood treatment apparatus for receiving an external functional means in accordance with the invention, and method] as well as in the German Patent Application No. 10 2009 012 632.5 having the title Abdichtungseinrichtung zum Abdichten eines Volumens einer medizinischen Behandlungsanordnung gegen ein weiteres Volumen sowie Anordnung und Verfahren [Sealing means for sealing a volume of a medical treatment arrangement against another volume, as well as arrangement and method] as filed with the German Patent and Trademark Office on Mar. 10, 2009, the relevant disclosure of which is herewith fully incorporated by way of reference.

[0148] Substituate liquid may enter the extracorporeal blood circuit 1000 via the pre-dilution addition valve 291.

[0149] FIG. 2 shows a momentary status of configuration of the blood treatment apparatus 2000 during the blood emptying or blood recirculation process, wherein the substituate liquid is introduced into the extracorporeal blood circuit 1000 at an upstream position (relative to the conveying direction that is usual during a blood treatment) through the opened pre-dilution addition valve 291.

[0150] The substituate liquid may displace the blood between the pre-dilution addition valve 291 and the venous connection needle 7, i.e., the blood present upstream from the pre-dilution addition valve 291 in the arterial conduit portion 1 and the blood present in the venous conduit portion 3.

[0151] The displaced blood may be recirculated through the venous connection needle 7 into the patient's vascular system.

[0152] The substituate liquid is conveyed through the arterial conduit portion 1 of the extracorporeal blood circuit 1000 upstream from the pre-dilution addition valve 291 through the treatment means 15 and the venous conduit portion 3 towards the patient 3000.

[0153] At the same time, the blood present in the extracorporeal blood circuit 1000 in front of or downstream from the pre-dilution addition valve 291 in the conveying direction is conveyed through the arterial conduit portion 1 to the patient 3000.

[0154] Here, the substituate liquid is introduced from the pre-dilution addition valve 291 into the arterial conduit portion 1 arranged downstream from the pre-dilution addition valve 291 and conveyed in the direction towards the patient 3000.

[0155] The simultaneous emptying of blood from the arterial conduit portion 1 of the extracorporeal blood circuit 1000 and from the venous conduit portion 3 of the extracorporeal blood circuit 1000 may in the preferred manner take place with the same progress, i.e., the degree or extent of emptying (e.g., in percent of a conduit content) of the blood still present in the respective conduit portions 1 and 3 may be identical at any point of time.

[0156] Emptying or recirculation of the blood from the extracorporeal blood circuit 1000 may be terminated concurrently. For example, the blood pump 13 and the substituate pump 23 may be stopped shortly before the substituate liquid reaches the arterial connection needle 5, and correspondingly shortly before the substituate liquid reaches the venous connection needle 7.

[0157] As an alternative, the substituate liquid mayas was already mentioned in the foregoingalso or additionally also be introduced into the extracorporeal blood circuit 1000 via the post-dilution addition valve 311.

[0158] The performance of the method of the invention does, however, substantially correspond to the manner of proceeding indicated in the foregoing for the substituate liquid supplied by means of pre-dilution, so that reference is here made to these above explanations.

[0159] FIG. 3 shows a schematic diagram of an extracorporeal blood system including an arterial ABD (air bubble detector) or air-recognition detector for performing methods of the invention. The represented components are essentially already known from FIGS. 1 and 2. In comparison therewith, there are additionally only present a hydraulic system 39, an arterial ABD (air bubble detector) 41, and a venous ABD 43.

[0160] The pumping directions indicated by arrows drawn in solid lines correspond to the regular directions, or forward directions. The pumping direction of the blood pump 13 indicated by dotted lines corresponds to its reverse operation, or suction by the blood pump 13.