APPARATUS FOR EXTRACORPOREAL BLOOD TREATMENT

Abstract

An apparatus for extracorporeal blood treatment comprises a control unit (100) connected to a blood pump (10) configured to deliver a blood flow rate in a blood circuit of the apparatus (1), to a diuretic pump (27) configured to deliver a flow rate (Q.sub.d) of a 5diuretic (e.g. furosemide) and to an osmotic agent pump (30) configured to deliver a flow rate (Q.sub.oa) of an osmotic agent (e.g. albumin) to be infused in the blood circuit or in the vascular system of the patient (P). The control unit (100) is configured for receiving at least one input patient parameter (e.g. blood 10pressure) and/or at least one input apparatus parameter (e.g. access pressure) and, during an extracorporeal blood treatment, to drive the diuretic pump (27) and/or the osmotic agent pump (30) as a function of said at least one input patient parameter and/or as a function of at least one input apparatus parameter, in order to15achieve an improved and better fluid removal from the patient (P).

Claims

1-20. (canceled)

21. An apparatus for extracorporeal blood treatment, comprising: a treatment unit; a blood circuit coupled to the treatment unit and comprising a blood removal line and a blood return line connectable to a vascular system of a patient; a blood pump coupled to a pump section of the blood circuit to deliver a blood flow rate; an effluent line connected to the treatment unit; an effluent pump coupled to a pump section of the effluent line to deliver an effluent flow rate; a source of a diuretic coupled to a diuretic pump and connected to the blood circuit or connectable to the vascular system of the patient, wherein the diuretic pump is configured to deliver a diuretic flow rate; a source of an osmotic agent coupled to an osmotic agent pump and connected to the blood circuit or connectable to the vascular system of the patient, wherein the osmotic agent pump is configured to deliver an osmotic agent flow rate; a control unit connected to the blood pump, the diuretic pump and the osmotic agent pump and configured to receive an input patient parameter and/or an input apparatus parameter; wherein, during an extracorporeal blood treatment, the control unit is configured to control the diuretic pump and/or the osmotic agent pump as a function of the input patient parameter and/or as a function of the input apparatus parameter.

22. The apparatus of claim 21, comprising a sensor connected to the control unit, wherein the sensor is configured to detect measured values of the input patient parameter and/or the input apparatus parameter.

23. The apparatus of claim 22, wherein the control unit is configured TO monitor said measured values over time and for controlling the diuretic pump and/or the osmotic agent pump as a function of variation over time of the measured values.

24. The apparatus of claim 21, wherein the control unit is configured to: receive a prescription value of the input patient parameter and/or the input apparatus parameter; and control the diuretic pump and/or the osmotic agent pump as a function of the prescription value of the input patient parameter and/or the input apparatus parameter.

25. The apparatus of claim 24, wherein the control unit is configured to control the diuretic pump and/or the osmotic agent pump as a function of a comparison between the prescription value with measured values of the input patient parameter and/or the input apparatus parameter.

26. The apparatus of claim 22, wherein the sensor is configured to detect the measured values of one or more of the following input patient parameters: heart rate, blood pressure, urine output, consciousness level, body weight, creatinine, hematocrit, level of electrolytes; wherein the control unit is configured to receive a prescription value of one or more of the following input apparatus parameter: blood flow rate, effluent flow rate, filtration flow rate; and wherein the sensor is configured to detect the measured values of one or more of the following input apparatus parameters: blood flow rate, effluent flow rate, filtration flow rate, access pressure, return pressure.

27. The apparatus of claim 25, further comprising: an infusion line connected to the blood circuit and to a source of an infusion fluid; an infusion pump coupled to a pump section of the infusion line and configured to deliver an infusion flow rate; a dialysis line connected to the treatment unit and to a source of a dialysis fluid; a dialysis pump coupled to a pump section of the dialysis line and configured to deliver a dialysis flow rate; wherein the control unit is configured to receive the prescription value of the one or more of the following input apparatus parameter: infusion flow rate and dialysis flow rate.

28. The apparatus of claim 27, wherein the sensor is configured to detect the measured values of one or more of the following input apparatus parameters: infusion flow rate and dialysis flow rate.

29. The apparatus of claim 26, wherein the control unit is configured to perform the following procedure: when, at the start of the extracorporeal blood treatment, the access pressure is above a high access pressure threshold and the blood pressure is above a blood pressure threshold or within an access pressure range, the control unit is configured to operate the blood pump to increase the blood flow rate and/or operate the effluent pump to increase the effluent flow rate and the filtration flow rate and/or operate the diuretic pump to start or increase the diuretic flow rate; when, at the start of the extracorporeal blood treatment, the access pressure is below a low access pressure threshold and the blood pressure is below a blood pressure threshold, the control unit is configured to operate the blood pump to decrease the blood flow rate and/or operate the effluent pump to decrease the effluent flow rate and the filtration flow rate and/or operate the osmotic agent pump to start or increase the osmotic agent and/or operate the diuretic pump to start or increase the diuretic flow rate.

30. The apparatus of claim 29, wherein the control unit is configured to perform the following procedure: when the access pressure decreases over time, the control unit is configured to operate the diuretic pump and/or the osmotic agent pump to deliver the diuretic flow rate and/or the osmotic agent flow rate; or when the access pressure increases over time, the control unit is configured to take no action or operate the effluent pump to increase the effluent flow rate and the filtration flow rate.

31. The apparatus of claim 26, wherein, when, at the start of the extracorporeal blood treatment, the creatinine is above a selected creatinine threshold indicating chronic kidney disease, the control unit is configured to operate the diuretic pump to increase the diuretic flow rate.

32. The apparatus of claim 21, wherein the control unit is configured to perform the following procedure: when the creatinine starts decreasing over time and/or the urine output starts decreasing over time, the control unit is configured to operate the diuretic pump to increase the diuretic flow rate and/or operate the osmotic pump to start; when the creatinine starts increasing over time and/or the urine output starts decreasing over time, the control unit is configured to operate the diuretic pump to decrease the diuretic flow rate.

33. The apparatus of claim 22, further comprising: an infusion line connected to the blood circuit and to a source of an infusion fluid; an infusion pump coupled to a pump section of the infusion line; wherein, when the creatinine starts increasing over time and/or the urine output starts decreasing over time, the control unit is configured to operate the infusion pump to deliver the infusion fluid through the infusion line at an infusion flow rate.

34. The apparatus of claim 26, wherein the control unit is configured to perform the following procedure: when hematocrit increases over time, the control unit is configured to operate the diuretic pump to decrease the diuretic flow rate; or when the urine output increases over time, the control unit is configured to operate the infusion pump to start or to increase the infusion flow rate, and, if the urine output still increases over time and hematocrit starts decreasing, the control unit is configured to operate the infusion pump to maintain the infusion flow rate.

35. The apparatus of claim 21, wherein the control unit is configured to receive data of the diuretic and/or data of the osmotic agent.

36. The apparatus of claim 21, wherein the osmotic agent comprises albumin or amino acids or mannitol or hypertonic saline or glucose solution; and wherein the diuretic comprises furosemide or torsemide or bumetanide or ethacrynic acid or metolazone or chlorthalidone or hydrochlorothiazide or chlorothiazide or spironolactone or eplererone.

37. The apparatus of claim 21, wherein the apparatus comprises a treatment machine including the control unit and the blood pump, wherein the treatment machine further comprises the osmotic agent pump and/or the diuretic pump.

38. The apparatus of claim 21, wherein the apparatus comprises a treatment machine including the control unit and the blood pump, wherein the osmotic agent pump and/or the diuretic pump is/are external to the treatment machine.

39. The apparatus of claim 21, wherein a diuretic line is connected to the source of a diuretic and either to the patient or to the blood circuit, the diuretic pump being coupled to a pump section of the diuretic line to deliver the diuretic flow rate; wherein an osmotic agent line is connected to the source of an osmotic agent and either to the patient or to the blood circuit, the osmotic agent pump being coupled to a pump section of the osmotic agent line to deliver the osmotic agent flow rate; wherein the apparatus comprises an integrated disposable set, wherein the treatment unit, the blood circuit, and the effluent line are grouped together and connected in the integrated disposable set, wherein one or more of the diuretic line and the osmotic agent line is connected to the integrated disposable set.

40. The apparatus of claim 21, further comprising: an auxiliary line connected to the blood circuit and to a source of a compensation substance comprising potassium and/or bicarbonate; a pump or syringe coupled to a pump section of the auxiliary line and configured to deliver a flow rate of the compensation substance; wherein the input apparatus parameter further comprises the flow rate of the compensation substance.

41. The apparatus of claim 21, wherein the control unit is configured to pause delivery of antihypertensive medication during the extracorporeal blood treatment.

42. The apparatus of claim 30, wherein, when the access pressure decreases over time, the control unit is configured to perform the following procedure: when the access pressure keeps on decreasing over time, the control unit is configured to: start operating the osmotic agent pump or operate the osmotic agent pump to increase the osmotic agent flow rate; and/or start operating the diuretic pump or operate the diuretic pump to increase the diuretic flow rate; when the access pressure starts increasing over time, the control unit is configured to: operate the diuretic pump to maintain the diuretic flow rate; and/or operate the osmotic agent pump to maintain the osmotic agent flow rate.

43. The apparatus of claim 26, wherein: when the blood pressure is within a selected blood pressure range, the control unit is configured to: operate the blood pump to increase the blood flow rate, operate the diuretic pump to increase the diuretic flow rate, and operate the effluent pump to increase the effluent flow rate and the filtration flow rate; when the blood pressure is below a selected blood pressure threshold, the control unit is configured to: start operating the osmotic agent pump or operate the osmotic agent pump to increase the osmotic agent flow rate until the blood pressure is stabilized, and start operating the diuretic pump or operate the diuretic pump to increase the diuretic flow rate.

44. The apparatus of claim 21, wherein the apparatus is a continuous renal replacement therapy system for intensive care treatments.

45. An apparatus for extracorporeal blood treatment, comprising: a treatment unit; a blood circuit coupled to the treatment unit and comprising a blood removal line and a blood return line connectable to a vascular system of a patient; a blood pump coupled to a pump section of the blood circuit to deliver a blood flow rate; an effluent line connected to the treatment unit; an effluent pump coupled to a pump section of the effluent line to deliver an effluent flow rate; a source of a diuretic coupled to a diuretic pump and connected to the blood circuit or connectable to the vascular system of the patient, wherein the diuretic pump is configured to deliver a diuretic flow rate; a source of an osmotic agent coupled to an osmotic agent pump and connected to the blood circuit or connectable to the vascular system of the patient, wherein the osmotic agent pump is configured to deliver an osmotic agent flow rate; a sensor; a control unit operably connected to the sensor, the blood pump, the diuretic pump and the osmotic agent pump, the control unit configured to receive an input patient parameter and an input apparatus parameter, the sensor configured to detect measured values of the input patient parameter and/or the input apparatus parameter; wherein the input patient parameters detected by the sensor comprise one or more of a heart rate, a blood pressure, a urine output, a consciousness level, a body weight, a creatinine value, a hematocrit value, and a level of electrolytes; wherein the control unit is configured to receive a prescription value of one or more of the following input apparatus parameters: blood flow rate, effluent flow rate, and filtration flow rate; and the sensor is configured to detect the measured values of one or more of the following input apparatus parameters: blood flow rate, effluent flow rate, filtration flow rate, access pressure, and return pressure; wherein the control unit is configured to check the access pressure and the blood pressure at the start of the extracorporeal blood treatment and perform the following procedure: when, at the start of the extracorporeal blood treatment, the access pressure is above a selected high access pressure threshold and the blood pressure is above a selected blood pressure threshold or within a selected access pressure range, the control unit is configured to operate one or more of: the blood pump to increase the blood flow rate, the effluent pump to increase the effluent flow rate, the diuretic pump to start or increase the diuretic flow rate; when, at the start of the extracorporeal blood treatment, the access pressure is below a selected low access pressure threshold and the blood pressure is below a selected blood pressure threshold, the control unit is configured to operate one or more of: the blood pump to decrease the blood flow rate, the effluent pump to decrease the effluent flow rate, the osmotic agent pump to start or increase delivery of the osmotic agent, the diuretic pump to start or increase the diuretic flow rate.

Description

DESCRIPTION OF THE DRAWINGS

[0111] The description will now follow, with reference to the appended figures, provided by way of non-limiting example, in which:

[0112] FIG. 1 schematically shows an extracorporeal blood treatment apparatus according to the invention;

[0113] FIG. 2 is a different embodiment of the extracorporeal blood treatment apparatus of the invention;

[0114] FIG. 3 is a flow chart of an example of a procedure implemented by the apparatus of the invention;

[0115] FIG. 4 is a flow chart of another example of a procedure implemented by the apparatus of the invention;

[0116] FIG. 5 is a flow chart of another example of a procedure implemented by the apparatus of the invention.

DETAILED DESCRIPTION

[0117] An apparatus 1 for extracorporeal blood treatment is schematically represented in FIG. 1. The apparatus 1 may be a continuous renal replacement therapy (CRRT) apparatus for intensive care treatments, for instance configured to deliver various therapies, like CCVH, CVVHDF, SCUF.

[0118] The apparatus 1 comprises a treatment or filtration unit 2 having a primary chamber 3 and a secondary chamber 4 separated by a semi-permeable membrane 5. Depending upon the treatment, the semi-permeable membrane 5 of the treatment unit 2 may be selected to have different properties and performances.

[0119] A blood circuit is coupled to the primary chamber 3 of the treatment unit 2. The blood circuit comprises a blood removal line 6 connected to an inlet 3a of the primary chamber 3, a blood return line 7 connected to an outlet 3b of the primary chamber 3.

[0120] The blood removal line 6 and blood return line 7 are configured for connection to a cardiovascular system of a patient P.

[0121] In use, the blood removal line 6 and the blood return line 7 are connected to a needle or to a catheter or other access device which is then placed in fluid communication with the patient P vascular system, such that blood may be withdrawn through the blood removal line 6, flown through the primary chamber 3 and then returned to the patient's vascular system through the blood return line 7. An air separator, such as a deaeration chamber 8, may be present on the blood return line 7. Moreover, a monitor valve 9 may be present on the blood return line 7, downstream the deaeration chamber 8.

[0122] The blood flow through the blood circuit is controlled by a blood pump 10, for instance a peristaltic blood pump, acting either on the blood removal line 6 or on the blood return line 7. The embodiment of FIG. 1 shows the blood pump 10 coupled to a pump section of the blood removal line 6.

[0123] A dialysis circuit is connected to the secondary chamber 4 of the filtration unit 2 and comprises a dialysis line 11 connected to an inlet 4a of the secondary chamber 4 and an effluent line 12 connected to an outlet 4b of the secondary chamber 4 and to a drain, not shown.

[0124] An effluent pump 13 is located on the effluent line 12 and is able to recall fluid from the second chamber 4. The dialysis line 11 is connected to a source 14, e.g. a bag or a preparation device, of fresh dialysis fluid and a dialysis pump 15 is located on the dialysis line 11 and is able to pump fluid to the second chamber 4.

[0125] The apparatus 1 further comprises an infusion circuit comprising at least one infusion line. The infusion circuit shown in the embodiment of FIG. 1 comprises a pre-blood pump line 16, a pre-infusion line 17 and a post-infusion line 18.

[0126] The pre-blood pump line 16 is connected to the blood removal line 6 upstream of the blood pump 10 and to a first source 19 of infusion fluid, e.g. a bag. A pre-blood pump 20 is located on the pre-blood pump line 16 and is able to pump fluid from the first source 19 to the blood circuit.

[0127] The pre-infusion line 17 is connected to the blood removal line 6 downstream of the blood pump 10 and upstream of the treatment unit 2 and to a second source 21 of infusion fluid, e.g. a bag. A pre-infusion pump 22 is located on the pre-infusion line 17 and is able to pump fluid from the second source 21 to the blood circuit.

[0128] The post-infusion line 18 is connected to the blood return line 7 downstream of the treatment unit 2 and to a third source 23 of infusion fluid, e.g. a bag. A post-infusion pump 24 is located on the post-infusion line 18 and is able to pump fluid from the third source 23 to the blood circuit.

[0129] The apparatus 1 may also comprise one or more auxiliary line/s, not shown, connected to the blood circuit and to a source of at least one compensation substance, such as potassium or bicarbonate, and a pump or syringe configured to deliver a flow rate of the compensation substance, such as potassium or bicarbonate.

[0130] A diuretic line 25 is connected to a source 26 of at least one diuretic and to the blood circuit. A diuretic pump 27 is configured to be coupled to a pump section of the diuretic line 25 to deliver a diuretic flow rate Q.sub.d.

[0131] The diuretic may be or may comprise furosemide, torsemide or bumetanide, ethacrynic acid, metolazone, chlorthalidone, hydrochlorothiazide, chlorothiazide, spironolactone, eplererone.

[0132] For instance, the diuretic may be a solution of sodium chloride mixed with furosemide.

[0133] An osmotic agent line 28 is connected to a source 29 of at least one osmotic agent and to the blood circuit. An osmotic agent pump 30 is configured to be coupled to a pump section of the osmotic agent line 28 to deliver an osmotic agent flow rate Q.sub.oa.

[0134] The osmotic agent may be or may comprise albumin, amino acid, mannitol, hypertonic saline, glucose solution.

[0135] A control unit 100 is connected and controls the blood pump 10, the effluent pump 13, the dialysis pump 15, the pre-blood pump 20, the pre-infusion pump 22 and the post-infusion pump 24 to regulate a blood flow rate Q.sub.b in the blood circuit, a dialysis flow rate Q.sub.dial crossing the dialysis line 11, an effluent flow rate Q.sub.eff crossing the effluent line 12, an infusion flow rate Q.sub.pbp crossing the pre-blood pump line 16, an infusion flow rate Q.sub.pre crossing the pre-infusion line 17, an infusion flow rate Q.sub.post crossing the post-infusion line 18.

[0136] Through the control of the dialysis flow rate Q.sub.dial crossing the dialysis line 11 and/or of the effluent flow rate Q.sub.eff crossing the effluent line 12, the control unit 100 is also configured to control/regulate a filtration flow rate Q.sub.fil in the treatment unit 2 and/or a patient fluid removal rate Q.sub.pfr.

[0137] The control unit 100 also controls the diuretic pump 27 and the osmotic agent pump 30 to control respectively the diuretic flow rate Q.sub.d and the osmotic agent flow rate Q.sub.oa.

[0138] Flow rate sensors, not shown in the attached drawings, may be placed on the blood circuit, on the dialysis line 11, on the effluent line 12, on the infusion lines 16, 17, 18, on the diuretic line 25, on the osmotic agent line 28 and connected to the control unit 100 to detect and/or control the flow rates of blood and fluids in the apparatus 1 (i.e. blood flow rate Q.sub.b, dialysis flow rate Q.sub.dial, effluent flow rate Q.sub.eff, infusion flow rates Q.sub.pbp, Q.sub.pre, Q.sub.post, diuretic flow rate Q.sub.d, osmotic agent flow rate Q.sub.oa and also filtration flow rate Q.sub.fil and patient fluid removal rate Q.sub.pfr).

[0139] An access pressure sensor 31 is placed on the blood removal line 6 and is connected to the control unit 100 to monitor an access pressure P.sub.acc. A return pressure sensor 32 is placed on the blood return line 7, for instance coupled to the deaeration chamber 9, and is connected to the control unit 100 to monitor a return pressure P.sub.ret.

[0140] Sensors are also provided to detect measured values of patient parameters, such as heart rate HR, blood pressure BP, urine output UO, consciousness level CL, body weight BW, creatinine Cr, hematocrit Htc, level of electrolytes. These sensors may be known and commonly used.

[0141] For instance, a heart rate sensor may be: a patch, a wristband or an armband, a chest strap, a wearable electrode based ECG. A weight scale may be used to measure the body weight BW. An urometer may be used for measuring urine output UO. An optical sensor may be used to measure hematocrit Htc. A digital blood pressure on the wrist, on the finger or upper arm of the patient P, may be used to monitor patient blood pressure BP. Saturation devices may also be used to retrieve information about heart rate that can indicate low blood pressure, since heart rate increases when blood pressure is getting lower (this may allow to sense a blood pressure decrease before it actually occurs). Temperature sensor to detect temperature at extremities of the patient may be used to infer blood pressure, since a low temperature means low blood pressure. For consciousness, a BIS monitor (bispectral index) may be used.

[0142] These sensors for detecting patient parameters may be connected to the control unit 100 to transmit values to the control unit 100 during the extracorporeal blood treatment (e.g. urine output UO and/or consciousness level CL and/or heart rate HR and/or hematocrit Htc). In this case, these patient parameters are measured continuously and continuously received by the control unit 100.

[0143] The sensors for detecting patient parameters may also be part of other devices which show the values such that the medical staff may enter them in the control unit 100. One or more of the patient parameters may be laboratory values (e.g. creatinine Cr or body weight BW or blood pressure BP). In these cases, these patient parameters are entered into the control unit 100 one or more times during the treatment or before the treatment starts.

[0144] The control unit 100 may be an electronic control unit comprising at least a CPU, a memory and input/output devices. The control unit 100 comprises or is connected to an interface 110 configured to display data and/or allow a user to input data. For instance, the interface comprises a display, e.g. a touch screen, and/or buttons or a keyboard.

[0145] The apparatus 1 may comprise a treatment machine 200 and an integrated disposable set configured to be coupled to the treatment machine.

[0146] The treatment machine comprises the cited blood pump 10, effluent pump 13, dialysis pump 15, pre-blood pump 20, pre-infusion pump 22, diuretic pump 27, osmotic agent pump 30, control unit 100 with the interface 110, flow rate sensors. The treatment machine may comprise also the access pressure sensor 31 and the return pressure sensor 32 or the access pressure sensor 31 and the return pressure sensor 32 may be part of the integrated disposable set. The treatment machine comprises also all the other elements and/or devices configured to receive and hold parts of the integrated disposable set.

[0147] The integrated disposable set comprises the treatment unit 2, the blood circuit, the effluent line 12, the dialysis line 11, the infusion lines 16, 17, 18, the diuretic line 25 and the osmotic agent line 28 which are grouped together.

[0148] In another embodiment, shown schematically in FIG. 2, the diuretic pump 27 and the osmotic agent pump 30 are part of an independent device 300 and not of the treatment machine 200. The treatment machine 200 comprises the blood pump 10, the effluent pump 13, the pre-infusion pump 22 and the control unit 100 as detailed above regarding FIG. 1. The independent device 300 comprises the diuretic pump 27 and the osmotic agent pump 30. The diuretic pump 27 and the osmotic agent pump 30 may be connected and controlled by a control unit 310 of the independent device 300 and this control unit 310 of the independent device 300 is connected to the control unit 100 of the treatment machine 100.

[0149] In other embodiments, not shown, the diuretic line 25 and the osmotic agent line 28 may be connected directly to the vascular system of the patient P instead of to the blood circuit.

[0150] In a further embodiment, the treatment machine 200 may include the blood circuit (blood removal line 6 and blood return line 7), the blood pump 10, the effluent line 12, the effluent pump 13, the treatment unit 2, and the control unit 100 as detailed above regarding FIG. 2. The here described treatment machine 200 is configured for ultrafiltration (or SCUF) in the field of e.g., congestive heart failure treatments. In this specific CHF treatment, the blood removal line 6 and blood return line 7 may be connected to peripheral veins of the patient to (e.g., slowly) remove excess water. Required infusions (e.g., diuretics and/or osmotic agents) may be connected directly to the vascular system of the patient P instead of to the blood circuit or to the blood circuit if required/proper).

[0151] The control unit 100 is configured and/or programmed for receiving one or more input patient parameter and/or one or more input apparatus parameter and for driving, during the extracorporeal blood treatment, the diuretic pump 27 and the osmotic agent pump 30 as a function of the input patient parameter/s and/or input apparatus parameter/s, to make sure that the more optimal treatment is given to the patient P to achieve the more optimal fluid removal.

[0152] The control unit 100 is therefore configured for implementing a script or algorithm and a method for controlling a patient fluid removal in the apparatus for extracorporeal blood treatment.

[0153] The input patient parameters and the input apparatus parameters may be prescription values and/or values measured through the sensors and/or devices previously listed.

[0154] According to some embodiments, the control unit 100 may be configured and/or programmed for monitoring the measured values over time and driving the diuretic pump and/or the osmotic agent pump as a function of variation over time of the measured values.

[0155] According to some embodiments, the control unit is configured and/or programmed for driving the diuretic pump and/or the osmotic agent pump as a function of the prescription value of the input patient parameter/s and/or the input apparatus parameter/s, for instance as a function of a comparison between said prescription value with the measured values of the input patient parameter and/or the input apparatus parameter.

[0156] According to examples of the procedure performed by the control unit 100 or of the method, the following input parameters.

Prescription Values

[0157] WL Total patient weight loss or fluid removal goal [0158] T Total treatment time

Types of Diuretic and Osmotic Agents

[0159] Diuretic: e.g. furosemide [0160] Osmotic agent: e.g. albumin

Measured Values

Input Apparatus Parameters

[0161] Q.sub.d diuretic flow rate [0162] Q.sub.oa osmotic agent flow rate [0163] Q.sub.b blood flow rate [0164] Q.sub.pbp infusion flow rate crossing pre-blood pump line [0165] Q.sub.pre infusion flow rate crossing pre-infusion line [0166] Q.sub.post infusion flow rate crossing post-infusion line [0167] Q.sub.dial dialysis flow rate [0168] Q.sub.eff effluent flow rate [0169] Q.sub.fil filtration flow rate [0170] Q.sub.pfr patient fluid removal rate [0171] P.sub.acc access pressure [0172] P.sub.ret return pressure
wherein Q.sub.eff=Q.sub.dial+Q.sub.fil=Q.sub.dial+Q.sub.pfr+Q.sub.pbp+Q.sub.pre+Q.sub.post
if Q.sub.oa and Q.sub.d are negligible.

Input Patient Parameters

[0173] UO urine output (measured continuously) [0174] CL consciousness level (measured continuously) [0175] HR heart rate (measured continuously) [0176] Htc hematocrit [0177] BW Body weight (lab value) [0178] BP Blood pressure (lab value) [0179] Cr Creatinine (lab value)

[0180] At the start of the treatment, the following parameters are set as a function of the total patient weight loss or fluid removal goal WT and the total treatment time T. [0181] Q.sub.bset set blood flow rate [0182] Q.sub.dialset set dialysis flow rate [0183] Q.sub.effset set effluent flow rate [0184] Q.sub.dset set diuretic flow rate [0185] P.sub.acc high set high access pressure threshold [0186] P.sub.acc low set low access pressure threshold [0187] P.sub.ret low set low return pressure threshold [0188] BP.sub.thr set blood pressure threshold [0189] Htc.sub.thr set hematocrit threshold [0190] Cr.sub.thr set creatinine threshold

[0191] At the start of the treatment, the following parameters may be set equal to zero.

[0192] Q.sub.oa=0 [0193] Q.sub.pbp=0 [0194] Q.sub.pre=0 [0195] Q.sub.post=0

[0196] Therefore: Q.sub.fil=Q.sub.effQ.sub.dial

[0197] The script or algorithm in the control unit 100 may be able to reach the fluid removal goal WT at set total treatment time T if no problems occur in regards of the access pressure P.sub.acc and the blood pressure P.sub.acc. If problems occur with the access pressure P.sub.acc and the blood pressure P.sub.acc, the filtration flow rate Q.sub.fil that may be set is limited and the time to reach the goal will be longer. The script may also consider stops such as pauses in treatment, bag changes, other alarms but also recirculation etc.

[0198] The following are examples of the method implemented by the control unit 100.

[0199] If the access pressure P.sub.acc is above the high access pressure threshold P.sub.acc high, for instance of 250 mmHg (e.g. high access pressure indicates high blood volume), or within an access pressure range, for instance between 100 mmHg and 160 mmHg, commanding the effluent pump 13 to increase the effluent flow rate Q.sub.eff and the filtration flow rate Q.sub.fil.

[0200] If the access pressure P.sub.acc is below the low access pressure threshold P.sub.acc low, (e.g. access pressure that is too low due to hypotension or either there is some hindrance in the blood removal line 6 (due for instance to folding of the catheter or kinked or twisted) or it is too close to the vascular wall or any other problem where the flow is not working properly due to the access not working), commanding the blood pump 10 to reduce the blood flow rate Q.sub.b and/or commanding the effluent pump 13 to reduce the effluent flow rate Q.sub.eff and the filtration flow rate Q.sub.fil and/or commanding the osmotic agent pump 30 and/or the diuretic pump 27 to reduce or increase the diuretic flow rate Q.sub.d and/or the osmotic agent flow rate Q.sub.oa.

[0201] The diuretic flow rate may be between 40 mg/h and 120 mg/h (4 mg/minute) and the osmotic agent flow rate may be between 10 mg/h and 150 mg/h.

[0202] Referring to the flow chart of FIG. 3, if P.sub.acc(t=0, i.e. at the start of the treatment)>P.sub.acc high and BP is in an acceptable range (e.g. >BP.sub.thr=100 mmHg systolic), then increase Q.sub.b and/or increase Q.sub.d and/or Q.sub.fil.

[0203] If P.sub.acc(t=0)<P.sub.acc low, and BP<BP.sub.thr=100 mmHg systolic, then decrease Q.sub.b and/or decrease Q.sub.fil and/or start Q.sub.oa (albumin) and/or increase Q.sub.d to increase blood pressure (FIG. 3).

[0204] Referring to the flow chart of FIG. 4, if the access pressure P.sub.acc decreases over time (e.g. if the access pressure at instant t=0 is greater than the access pressure at instant t=1), meaning that blood is more concentrated, i.e. there is less fluid in blood, then starting the diuretic pump 27 and/or the osmotic agent pump 30 to deliver the diuretic flow rate Q.sub.d and/or the osmotic agent flow rate Q.sub.oa; the osmotic agent forces fluid into the central circulation and diuretic infusion removes fluids through urine. One of the positive aspects of diuretics, such as furosemide, is that they can help remove some fluid in the lungs. If the access pressure P.sub.acc keeps on decreasing over time (e.g. the access pressure at instant t=1 is greater than the access pressure at instant t=2), meaning that no further fluid in blood is available or not high enough concentration of diuretics is present to increase the plasma, then starting the osmotic agent pump 30 and/or the diuretic pump 27 or commanding the diuretic pump 27 to increase the diuretic flow rate Q.sub.d and/or commanding the osmotic agent pump 30 to increase the osmotic agent flow rate Q.sub.oa. If the access pressure P.sub.acc starts increasing over time (e.g. if the access pressure at instant t=2 is greater than the access pressure at instant t=1), meaning that a good result has been achieved, then commanding the diuretic pump 27 to maintain the diuretic flow rate Q.sub.d and/or commanding the osmotic agent pump 30 to maintain the osmotic agent flow rate Q.sub.oa (FIG. 3).

[0205] If the access pressure P.sub.acc increases over time (e.g. if the access pressure at instant t=1 is greater than the access pressure at instant t=0), taking no action or commanding the effluent pump 13 to increase the effluent flow rate Q.sub.eff and the filtration flow rate Q.sub.fil, in order to increase fluid removal from patient P. Since good conditions are present, the filtration flow rate Q.sub.fil may be increased to remove more fluid faster (FIG. 4).

[0206] If the blood pressure BP is within a blood pressure range, then increase the blood flow rate Q.sub.b, increase the diuretic flow rate Q.sub.d and increase the effluent flow rate Q.sub.eff and the filtration flow rate Q.sub.fil. Since good conditions are present, the filtration flow rate may be increased to remove more fluid faster.

[0207] If the blood pressure BP is below a blood pressure threshold, start the osmotic agent pump 30 or commanding the osmotic agent pump 30 to increase the osmotic agent flow rate Q.sub.oa till the blood pressure BP is stabilized and then starting the diuretic pump 27 or commanding the diuretic pump 27 to increase the diuretic flow rate Q.sub.d.

[0208] If the blood pressure BP is low, i.e. below a blood pressure threshold, and the access pressure P.sub.acc is outside an access pressure range, the infusion flow rate is started, e.g. of saline or glucose. Some patients may have the contradicting problem that the intravascular water concentration is low but there is an increased amount of solution in tissue (extracellular). In these conditions, addition of solution and at the same time removal of solution may be needed.

[0209] If the creatinine Cr is outside a creatinine range (increase in creatinine may indicate risk for damage on the kidneys) and/or the hematocrit Htc is outside a hematocrit range (risk for clotting), then a less aggressive treatment is performed. For instance, the blood flow rate Q.sub.b is reduced and/or the effluent flow rate Q.sub.eff and the filtration flow rate Q.sub.fil are reduced while the diuretic flow rate Q.sub.d and/or the osmotic agent flow rate Q.sub.oa are reduced or increased, depending on the specific circumstances.

[0210] Referring to FIG. 5, if Cr(t=0) is above the creatinine threshold Cr.sub.thr indicating Chronic Kidney Disease (CKD), then chose a high diuretic flow rate Q.sub.d and then: [0211] if Cr(t=0)>Cr(t=1) and/or UO(t=0)>UO(t=1), then increase the diuretic flow rate Q.sub.d and/or give osmotic agent (especially if blood pressure BP is low); [0212] if Cr(t=0)<Cr(t=1) and UO(t=0)>UO(t=1), then decrease the diuretic flow rate Q.sub.d and/or give infusion fluid (especially if blood pressure BP is low).

[0213] If the above outlined situation of creatinine is combined with Htc (t=0)<Htc (t=1) (indicating low plasma concentration and that an extra accumulated fluid is not in the vessels but outside), then add glucose or a buffer solution or saline depending on other underlying problems the patient may have.

[0214] If Htc (t=0)<Htc (t=1), then decrease the diuretic flow rate Q.sub.d, or, if UO (t=0)<UO (t=1), then give infusion fluid and check Htc and UO again after some time (e.g. 1 hour). If after such time the urine output UO is still increasing and the hematocrit Htc is getting better (i.e. decreasing), then continue with therapy as suggested and continue infusion of infusion fluid.

[0215] If the urine output UO increases, then one may increase the diuretic flow rate Q.sub.d and adapt for the goal being reached and filtration flow rate Q.sub.fil may be decreased, since it is always better to remove fluid through natural means.

[0216] If the access pressure P.sub.acc is high (P.sub.acc(t=0)>P.sub.acc high) and the hematocrit is high (Htc>Htc.sub.thr) and the return pressure P.sub.ret is low (P.sub.ret<P.sub.ret low), then check the access for possible clot formation.

[0217] If the access pressure P.sub.acc is above the high access pressure threshold P.sub.acc high or within the access pressure range and the blood pressure BP is greater than 100 mmHg systolic and UO (t=0)<UO (t=1) or, during the treatment, the patient shows clinical signs of fluid overload, such as shortness of breath etc., then administering a bolus (e.g. 40 mg to 80 mg) of diuretic (e.g. furosemide) and checking again blood pressure and the effect of such administration.

[0218] If heart rate HR starts increasing systematically and at the same time blood pressure BP decreases slightly, then a routine for continuous check of blood pressure is triggered or the blood flow rate Q.sub.b and/or the diuretic flow rate Q.sub.d is/are reduced. Then, if the blood pressure BP becomes stable these changes are maintained, otherwise, if the blood pressure BP increases, then the initial settings with higher diuretic flow rate Q.sub.d and/or blood flow rate Q.sub.b are recovered.

[0219] If BP<100 mmHg systolic, then give osmotic agent (e.g. albumin) and check blood pressure BP. If blood pressure BP increases, then maintain the diuretic flow rate Q.sub.d. If blood pressure BP is still low, then decrease the diuretic flow rate Q.sub.d and/or the blood flow rate Q.sub.b and/or give infusion fluid to increase the blood pressure BP.

[0220] If the urine output UO is below a urine threshold and the blood pressure BP is within the blood pressure range, then increase the effluent flow rate Q.sub.eff and the filtration flow rate Q.sub.fil and maintain the diuretic flow rate Q.sub.d.

[0221] If the urine output UO is not increasing during treatment but the blood pressure BP is high and the access pressure P.sub.acc is high, then increase the blood flow rate Q.sub.b and/or the diuretic flow rate Q.sub.d.

[0222] If patient P is taking antihypertensive medication, those are to be paused during the treatment.

[0223] The script or algorithm in the control unit 100 may also check a difference between the access pressure P.sub.acc and the return pressure P.sub.ret during the treatment and look at the results. If the pressure difference (P.sub.accP.sub.ret) is getting bigger, depending on which way, it can indicate either good effect of diuretics (if fluid is added to blood from extra/intracellular liquid) or unfavorable changes (if fluid is only removed from blood and not from extra/intracellular liquid and this may cause damage to kidneys). The script or algorithm may also check the effect of osmotic agent (e.g. albumin) and the time it takes to achieve good results.

[0224] The script or algorithm in the control unit 100 may also control the effluent flow rate Q.sub.eff, the dialysis flow rate Q.sub.dial,, the filtration flow rate Q.sub.fil and the patient fluid removal rate Q.sub.pfr and make sure that the changes in the diuretic flow rate Q.sub.d and the osmotic agent flow rate Q.sub.oa will be favorable (i.e. reduced along the treatment). If not, it will ask for e.g. creatinine Cr to make sure that the kidney have not worsened and/or calculate the post-filter hematocrit Htc.sub.pd to make sure that the blood has not been concentrated too much. For instance, the post-filter hematocrit Htc.sub.pd may be calculated through the following formula:

[00001]$Ht{c}_{pd}=Q_{b}60\left(\mathrm{Htc}/\left(Q_{b}60+Q_{\mathrm{pbp}}+Q_{\mathrm{pre}}-Q_{\mathrm{fil}}\right)\right)$

[0225] Then, the filtration flow rate Q.sub.fil may be continued to be increased as long as hematocrit Htc and creatinine Cr have not increased too much.

[0226] The control unit 100 may also command the apparatus 1 to send an alarm signal if the access pressure is below a low alarm access pressure threshold or above a high alarm access pressure threshold.

[0227] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.