Method for Priming an Extracorporeal Blood Circuit and Devices

Abstract

The present disclosure relates to a method for priming an extracorporeal blood circuit using a blood treatment apparatus comprising a dialysis liquid preparation system having, a source of water, a source of bicarbonate concentrate and a source of acid concentrate including sodium chloride while not having a source of sodium chloride only, the method including preparing a priming solution from said source (of water and said source of acid only to obtain an acid/water solution, wherein bicarbonate from the source of bicarbonate concentrate is absent from said solution, connecting an arterial line section of the extracorporeal blood circuit to an outlet of the dialysis liquid preparation system of the blood treatment apparatus, and filling the extracorporeal blood circuit with said priming solution.

Claims

1-12. (canceled)

13. A method of priming an extracorporeal blood circuit using a blood treatment apparatus comprising a dialysis liquid preparation system having a source of water, a source of bicarbonate concentrate and a source of acid concentrate including sodium chloride while not having or being connected to a source that comprises sodium chloride only or exclusively, the blood treatment apparatus configured to prepare a dialysis liquid from water, the bicarbonate concentrate and the acid concentrate only, wherein the extracorporeal blood circuit comprises an arterial line section, connectable to a patient, for drawing blood from the patient, a venous line section, connectable to the patient, for returning the blood to the patient, and a blood side compartment or blood chamber of a blood filter, the method comprising a first phase comprising: preparing a priming solution from the source of water and the source of acid concentrate only to obtain an acid/water solution, wherein bicarbonate from the source of bicarbonate concentrate is absent from the solution, connecting the arterial line section to an outlet of the dialysis liquid preparation system of the blood treatment apparatus and, filling the extracorporeal blood circuit with the priming solution.

14. The method according to claim 13, wherein during the first phase the temperature of the priming solution is kept below 35° C.

15. The method according to claim 13, wherein during the first phase the temperature of the priming solution is kept between 25° C. and 30° C.

16. The method according to claim 15, wherein the method further comprises a second phase, following the first phase, the second phase comprising: adding bicarbonate from the source of bicarbonate concentrate to the priming solution.

17. The method according to claim 16, wherein during the second phase the temperature of the priming solution is raised to at least 35° C.

18. The method according to claim 16, wherein the priming is continued for at least 5 minutes before the priming is considered as completed.

19. The method according to claim 18, wherein circulation of the priming solution within the extracorporeal circuit is continued for at least 5 minutes before the priming is considered as completed.

20. A control device or closed-loop control device configured to carry out or to initiate the method according to claim 13 in interaction with the blood treatment apparatus.

21. A blood treatment apparatus for the extracorporeal treatment of a patient’s blood, comprising the control device or closed-loop control device according to claim 20.

22. The blood treatment apparatus according to claim 21, wherein the blood treatment apparatus comprises a hemodialysis apparatus, hemofiltration apparatus or hemodiafiltration apparatus.

23. The blood treatment apparatus according to claim 21, wherein the blood treatment apparatus is configured for acute or chronic renal replacement therapy.

24. The blood treatment apparatus according to claim 23, further comprising sensors arranged and configured to measure a sodium concentration, in the priming solution.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The present disclosure is exemplarily explained with regard to the accompanying drawings in which same reference numerals refer to the same or similar components. In the figures the following applies:

[0058] FIG. 1 shows in a simplified, schematic representation a blood treatment apparatus with an extracorporeal blood circuit in a first embodiment or the representation of a flow diagram of a blood treatment apparatus, exemplarily embodied as a hemodiafiltration apparatus;

[0059] FIG. 2 shows a schematic representation of an exemplary implementation of the first phase of a method; and

[0060] FIG. 3 shows a schematic representation of an exemplary implementation of the second phase of the method of FIG. 2.

DETAILED DESCRIPTION

[0061] FIG. 1 shows an extracorporeal blood circuit 300, which can be connected to the vascular system of the patient (not shown) for a treatment via double-needle access, or via single-needle access, using, for example, an additional Y-connector (reference numeral Y) as shown in FIG. 1. The blood circuit 300 can optionally be present in sections thereof in or on a blood cassette.

[0062] Pumps, actuators and/or valves in the area of the blood circuit 300 are connected to a blood treatment apparatus 100 or for example, to a control device 150 comprised within.

[0063] The blood circuit 300 comprises (or is connected to) an arterial patient tubing clamp 302 and an arterial connection needle of an arterial section or of an arterial patient line, a blood withdrawal line or a first line 301. The blood circuit 300 further comprises (or is connected to) a venous patient tubing clamp 306 and a venous connection needle of a venous section, a venous patient line, blood return line or second line 305.

[0064] A blood pump 101 is provided in or on the first line 301, a substituate pump 111 is connected to a dialysis liquid inlet line 104 for conveying fresh dialysis liquid, which is filtered through a further filter (F2) (substituate). A substituate line 105 can be in fluid communication with the inlet line 104. Using the substituate pump 111, substituate can be introduced by pre-dilution via a pre-dilution valve 107, or by post-dilution via a post-dilution valve 109, into line sections via corresponding lines 107a or 109a, for example into the arterial line section 301 or into the venous line section 305 (here between a blood chamber 303b of a blood filter 303 and a venous air separation chamber or venous blood chamber 29) of the blood circuit 300

[0065] The blood filter 303 comprises the blood chamber 303b which is connected to the arterial line section 301 and the venous line section 305. A dialysis liquid chamber 303a of the blood filter 303 is connected to the dialysis liquid inlet line 104 leading to the dialysis liquid chamber 303a and a dialysate outlet line 102 leading away from the dialysis liquid chamber 303a which guides dialysate, i.e., used dialysis liquid. Dialysis liquid chamber 303a and blood chamber 303b are separated by a mostly semi-permeable membrane 303c. This membrane is what separates the blood side with the extracorporeal blood circuit 300 and the machine side with the dialysis liquid circuit or dialysate circuit, which is shown in FIG. 1 to the left of the membrane 303c.

[0066] The arrangement in FIG. 1 encompasses an optional detector 315 for detecting air and/or blood. The arrangement in FIG. 1 further encompasses one or two pressure sensors PS1 (upstream of the blood pump 101) and PS2 (downstream of the blood pump 101, which measures the pressure upstream of the blood filter 303 (“pre-hemofilter”)) at the positions shown in FIG. 1. Further pressure sensors may be provided, e.g., the pressure sensor PS3 downstream of the venous blood chamber 29.

[0067] An optional single-needle chamber 317 is used in FIG. 1 as a buffer and/or a compensating reservoir in a single-needle procedure in which the patient is connected to the extracorporeal blood circuit 300 via only one of the two blood lines 301, 305.

[0068] The arrangement in FIG. 1 additionally comprises an optional detector 319 for detecting air bubbles and/or blood.

[0069] An addition point 25 for Heparin may be optionally provided. Shown on the left in FIG. 1 is a mixing apparatus 63 being a dialysis liquid preparation system which, from containers A (for A concentrate via the concentrate supply 67) and B (for B concentrate via the concentrate supply 69), provides a predetermined mixture for the respective solution for use by the blood treatment apparatus 100 provides.

[0070] Alternatively, the mixing apparatus 63 as such can be omitted, and the two concentrates can be delivered successively into any fluid line and may come into contact with each other in any component of the blood treatment apparatus 100. After having been brought together in a common vessel (line, tubing, chamber, and so on), the so generated solution may be optionally thoroughly mixed or stirred, e.g., in a device 161 for balancing (e.g., a balancing chamber) as set forth below. Hence, the mixing apparatus 63 as mentioned herein is not restricted to a chamber as shown in FIG. 1. Rather, it may be any other vessel such as the fluid line denoted with 63 in FIG. 2 or FIG. 3

[0071] The solution may contain, in the heater 61 for example, warmed water from the water source 55 (on-line, e.g., as reverse osmosis water or from bags).

[0072] A pump 71, that may be referred to as a concentrate pump or sodium pump is in fluid communication with the mixing apparatus 63 and with a source having sodium, such as the container B, and/or conveys therefrom.

[0073] Furthermore, an outlet 53 for the effluent can be seen in FIG. 1. An optional heat exchanger 57 and a first flow pump 59, which is suitable for de-gassing, may complete the arrangement shown.

[0074] A further pressure sensor for measuring the filtrate pressure or the membrane pressure of the blood filter 303 may be provided as PS4 downstream of the blood filter 303 on the water-side, however preferably upstream of the ultrafiltration pump 131 in the dialysate outlet line 102. Further optional pressure measuring points P may also be provided.

[0075] Blood, which leaves the blood filter 303, passes through an optional venous blood chamber 29, which can comprise a de-aeration device 31 and/or may be in fluid communication with a further pressure sensor PS3.

[0076] The exemplary arrangement shown in FIG. 1 comprises a control device or closed-loop control device 150. This can be in wired or wireless signal communication with any of the components referred to herein - in particular or especially to the blood pump 101 - in order to control or regulate the blood treatment apparatus 100. It is optionally configured in order to carry out the method described herein, particularly automatically.

[0077] By using the device for on-line mixing of the dialysis liquid, a variation in the sodium content thereof controlled by the control device 150, is possible within certain limits. For this purpose, measurements determined via the conductivity sensors 163a, 163b may particularly be taken into account. Should an adjustment of the sodium content of the dialysis liquid (sodium concentration) or of the substituate be required or desired, this can be done by adjusting the delivery rate of the sodium pump 71.

[0078] Furthermore, the blood treatment apparatus 100 comprises means for conveying fresh dialysis liquid as well as dialysate. For this purpose, the first flow pump 59, which conveys fresh dialysis liquid towards the blood filter 303, is provided upstream of the blood filter 303. A first valve may be provided between the first flow pump 59 and the blood filter 303, which opens or closes the inlet to the blood filter 303 on the inlet side. A second optional flow pump 169 is provided, for example downstream of the blood filter 303, which conveys dialysate to the outlet 53. A second valve may be provided between the blood filter 303 and the second flow pump 169, which opens or closes the outlet on the outlet side.

[0079] Furthermore, the blood treatment apparatus 100 optionally comprises a device 161 for balancing the flow going into and coming out of the dialyzer 303 on the machine side. The device 161 for balancing is preferably arranged in a line section between the first flow pump 59 and the second flow pump 169.

[0080] The blood treatment apparatus 100 further encompasses means, such as the ultrafiltration pump 131, for the precise removal of a fluid volume from the balanced circuit as specified by the user and/or by the control device 150.

[0081] Sensors such as the optional conductivity sensors 163a, 163b serve to determine the conductivity, which in some embodiments is temperature-compensated, as well as the liquid flow upstream and downstream of the dialyzer 303.

[0082] Temperature sensors 165a, 165b can be provided individually or in groups. Temperature readings supplied by them can be used to determine a temperature-compensated conductivity.

[0083] A leakage sensor 167 is optionally provided.

[0084] Further flow pumps, in addition or as an alternative to, the one indicated with the reference numeral 169 for example, can also be provided.

[0085] A row of optional valves is each indicated in FIG. 1 with a V. By pass valves are indicated with a VB.

[0086] In some embodiments the control device 150 determines the electrolyte and/or liquid balancing based on the measurement readings of the afore-mentioned, optional sensors.

[0087] Filters F1 and F2 may be provided in series-connection.

[0088] The filter F1 here serves exemplarily, via the mixing apparatus 63, to produce sufficiently pure dialysis liquid, even when using impure water, which then flows through the blood filter 303, e.g., according to the counter-current principle.

[0089] Exemplarily, here the filter F2 serves to generate a sterile or sufficiently filtered substituate from the sufficiently pure dialysis liquid, which leaves the first filter F1, by filtering out pyrogenic substances, for example. This substituate can safely be added to the patient’s blood flowing extracorporeally and thus ultimately be supplied to the patient’s body.

[0090] The blood treatment apparatus 100 described herein is shown in FIG. 1 as a device for hemo(dia)filtration. However, hemodialysis devices also fall within the scope of the present disclosure, even though they are not specifically shown in the figures.

[0091] The present disclosure is not limited to the embodiment described above, this serves only as an illustration.

[0092] The arrows shown in FIG. 1 generally indicate the direction of flow in FIG. 1.

[0093] FIG. 2 shows a schematic representation of an exemplary implementation of the first phase of the method described herein. The components shown are all part of the hydraulic unit of the blood treatment apparatus 100. In particular, FIG. 1 shows the mixing apparatus 63 used for preparing the priming liquid. As stated before, the mixing apparatus 63 is not limited to the one shown in FIG. 1. Rather, the mixing can take place anywhere within the blood treatment apparatus 100 or the tubing attached to the blood treatment apparatus 100. In the example of FIG. 2, instead of feeding concentrates from sources A and B into a mixing apparatus 63 such as the one shown in FIG. 1, a fluid line into which the concentrates may be fed downstream the water source 55 is used as a mixing chamber.

[0094] During the first phase, the priming liquid contains no bicarbonate, a priming takes place with acid concentrate diluted in water only.

[0095] Water gained from a reverse-osmosis (RO) process or any other type of water such as tap water enters the mixing apparatus 63 from the water source 55.

[0096] Having passed an optional degassing device 60 the water may be heated in a heating apparatus 61 such that the temperature of the eventually generated priming liquid is between 25° C. and 35° C. (degrees Celsius).

[0097] Downstream of the heating apparatus 61 acid concentrate from source A is pumped into the water flow in the mixing apparatus 63.

[0098] As indicated by the symbol denoting the pump corresponding the source B of bicarbonate concentrate and the representation of the valve right downstream of the pump no bicarbonate is mixed into the thus generated water/acid solution.

[0099] A conductivity cell 163a may be used to monitor and control the [Na.sup.+] concentration of the priming liquid prepared in the mixing apparatus 63. In the first phase, a conductivity of 14.0 [mS] is measured.

[0100] A desirable [Na.sup.+] concentration is 137 mmol/l. As can be seen from FIG. 2, the [Na.sup.+] concentration of the priming liquid originates exclusively from the source A since no fluid and, hence, no sodium chloride or sodium [Na.sup.+] is contributed to the priming liquid from source B.

[0101] In the particular embodiment of FIG. 2, the container A comprises an acid concentrate for dialysis with sodium chloride in a concentration of 263 g/l NaCl. Further the container A comprises an acid, like citric acid or acetic acid, and preferably one or more of the following electrolytes, like magnesium chloride, calcium chloride and potassium chloride. For priming the extracorporeal circuit, the concentrate is diluted with water (33:1) to result in a priming solution comprising 137 mmol/l sodium.

[0102] FIG. 3 shows a schematic representation of an exemplary implementation of the second phase of the method of FIG. 2. The components shown in FIG. 3 are those of FIG. 2.

[0103] In the second phase bicarbonate concentrate is added to the priming liquid in preparation of the extracorporeal blood circuit 300 as is indicated by the icon representing the pump corresponding to the source B. In the particular setting shown in FIG. 3, the container A comprises 263 g/l NaCl. Its concentrate is used with a dilution factor 45:1 contributing 100 mmol/l sodium chloride, whereas the flow from container B contributes 37 mmol/l in an exemplary dilution having a dilution factor 25:1.

[0104] As in the first phase, the [Na.sup.+] concentration of the priming liquid is 137 mmol/l. However, the contribution from container A amounts to 100 mmol/l [Na.sup.+] and is, hence, less than before. In contrast to the first step, sodium chloride is contributed from the container B as well. In the example of FIG. 3, it also provides the lacking 37 mmol/l [Na.sup.+] needed for preparing a priming solution having a concentration of 137 mmol/l [Na.sup.+] as in the first phase.

[0105] The bicarbonate concentrate of container B may be saturated. In a saturated condition of the bicarbonate concentration of container B its sodium bicarbonate concentration may, in one exemplary embodiment, amount to 95.5 g/l at 20°. Those number are, however, not intended to be limiting, of course.

[0106] It is noted that the priming solution prepared in the first phase, which is exemplary described with respect to FIG. 2, may be used when circulating a liquid through parts of the extracorporeal blood circuit 300 and/or of the hydraulic system while a patient is temporarily disconnected from the blood treatment apparatus 100. Also, a solution used for rinsing parts of the extracorporeal blood circuit 300 and/or of the hydraulic system between two patients that are consecutively treated with more or less the same equipment. Before connecting the next patient to said equipment, the solution prepared by the mixing apparatus 63 will have been mixed as set forth with respect to the second phase, e.g., as described supra.

TABLE-US-00001 List of reference numerals 25 addition point for Heparin (optional) 29 venous blood chamber (optional) 31 de-aeration device 53 outlet 55 water source 57 heat exchanger 59 first flow pump 60 degassing device 61 heating apparatus 63 mixing apparatus 67 concentrate supply 69 concentrate supply 71 concentrate pump; sodium pump 100 blood treatment apparatus 101 blood pump 102 dialysate outlet line, effluent inlet line 104 dialysis liquid inlet line 105 substituate line 107 pre-dilution valve 107a line 109 post-dilution valve 109a line 111 pump for substituate 121 pump for dialysis liquid 131 pump for dialysate or effluent 150 control device or closed-loop control device 161 device 163a conductivity sensor 163b conductivity sensor 165a temperature sensor 165b temperature sensor 167 leakage sensor 169 second flow pump 300 extracorporeal blood circuit 301 first line (arterial line section) 302 first tubing clamp 303 blood filter or dialyzer 303a dialysis liquid chamber 303b blood chamber 303c semi-permeable membrane 305 second line (venous line section) 306 (second) tubing clamp 315 detector 317 single-needle chamber 319 detector F1 filter F2 filter [Na.sup.+] sodium concentration A container (source of acid) B container (source of bicarbonate) P pressure measuring points PS1 arterial pressure sensor (optional) PS2 arterial pressure sensor (optional) PS3 pressure sensor (optional) PS4 pressure sensor for measuring the filtrate pressure (optional) V valves VB bypass valves Y Y-connector