Fluid Volume Monitoring for Patients with Renal Disease

• US 20150151033A1
• Filed: 02/04/2015
• Published: 06/04/2015
• Est. Priority Date: 04/29/2011
• Status: Active Grant

• Current Assignee: Mozarc Medical US LLC
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Gerber, Martin, Burnes, John, Lyu, Suping, VenKatesh, Manda R., Pudil, Bryant
• Granted Patent: US 9,597,440 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/14503 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors A61B5/1459, A61B5/1464, A61B5/1473, A61B5/1482, A61B5/14865 take precedence
• CPC Class Codes: A61B 5/14535 for measuring haematocrit
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/4848 Monitoring or testing the effects of treatment, e.g. of medication
• CPC Class Codes: A61B 5/6866 Extracorporeal blood circuits, e.g. dialysis circuits
• CPC Class Codes: A61M 1/00 Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems catheters A61M25/00; tube connectors, tube couplings, valves or branch units specially adapted for medical use A61M39/00; devices for taking samples of blood A61B5/15; filters implantable into blood vessels A61F2/01
• CPC Class Codes: A61M 1/14 Dialysis systems; Artificial kidneys; Blood oxygenators semi-permeable membranes characterised by the material, manufacturing processes therefor B01D71/00; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1601 Control or regulation
• CPC Class Codes: A61M 1/1603 Regulation parameters
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1607 : before use, i.e. upstream of dialyser
• CPC Class Codes: A61M 1/1613 : Profiling or modelling of patient or predicted treatment evolution or outcome
• CPC Class Codes: A61M 1/28 : Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
• CPC Class Codes: A61M 1/34 : Filtering material out of the blood by passing it through a membrane, i.e. hemofiltration or diafiltration
• CPC Class Codes: A61M 1/3403 : Regulation parameters
• CPC Class Codes: A61M 1/342 : Adding solutions to the blood, e.g. substitution solutions for preventing coagulation A61M1/3672
• CPC Class Codes: A61M 1/3607 : Regulation parameters
• CPC Class Codes: A61M 1/3609 : Physical characteristics of the blood, e.g. haematocrit, urea
• CPC Class Codes: A61M 1/361 : before treatment
• CPC Class Codes: A61M 1/3612 : after treatment
• CPC Class Codes: A61M 2205/04 : implanted
• CPC Class Codes: A61M 2205/18 : with alarm
• CPC Class Codes: A61M 2205/33 : Controlling, regulating or measuring
• CPC Class Codes: A61M 2205/3303 : Using a biosensor
• CPC Class Codes: A61M 2205/3306 : Optical measuring means
• CPC Class Codes: A61M 2205/3313 : used specific wavelengths
• CPC Class Codes: A61M 2205/3331 : Pressure; Flow
• CPC Class Codes: A61M 2205/3334 : Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3375 : Acoustical, e.g. ultrasonic, measuring means
• CPC Class Codes: A61M 2205/3523 : using telemetric means
• CPC Class Codes: A61M 2205/50 : with microprocessors or computers
• CPC Class Codes: A61M 2205/52 : with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 2205/60 : with identification means
• CPC Class Codes: A61M 2205/70 : with testing or calibration facilities
• CPC Class Codes: A61M 2230/00 : Measuring parameters of the user
• CPC Class Codes: A61M 2230/005 : Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/20 : Blood composition characteristics
• CPC Class Codes: A61M 2230/207 : hematocrit
• CPC Class Codes: A61M 2230/208 : pH-value
• CPC Class Codes: A61M 2230/65 : Impedance, e.g. conductivity, capacity
• CPC Class Codes: B01D 2321/12 : Use of permeate
• CPC Class Codes: B01D 2321/40 : Automatic control of cleaning processes
• CPC Class Codes: B01D 61/00 : Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor separation of gases or vapours by diffusion B01D53/22
• CPC Class Codes: B01D 61/32 : Controlling or regulating
• CPC Class Codes: B01D 65/02 : Membrane cleaning or sterilisation ; Membrane regeneration
• CPC Class Codes: G16H 20/17 : delivered via infusion or injection
• CPC Class Codes: G16H 20/40 : relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 40/63 : for local operation
• CPC Class Codes: G16H 50/70 : for mining of medical data, e.g. analysing previous cases of other patients
• CPC Class Codes: G16Z 99/00 : Subject matter not provided for in other main groups of this subclass

Abstract

A method includes initiating a blood fluid removal session of a patient; monitoring an indicator of tissue fluid volume of the patient, or a portion thereof, during the blood fluid removal session; monitoring an indicator of blood fluid volume of the patient during the blood fluid removal session; determining whether a ratio of the indicator of tissue fluid volume to indicator of blood fluid volume is outside of a predetermined range; and altering the rate of fluid removal during the blood fluid removal session if the ratio is determined to be outside of the predetermined range. A blood fluid removal system may be configured to carry out the method.

Claims

1. A method, comprising:

initiating a blood fluid removal session of a patient with an initial blood fluid removal rate;

monitoring an indicator of tissue fluid volume of the patient during the blood fluid removal session;

monitoring an indicator of blood fluid volume of the patient during the blood fluid removal session;

determining a first indicator of tissue fluid volume and a first indicator of blood fluid volume;

acquiring a first set of data regarding the physiological health of the patient;

altering the rate of blood fluid removal to a second blood fluid removal rate;

determining a second indicator of tissue fluid volume and a second indicator of blood fluid volume;

acquiring a second set of data regarding the physiological health of the patient;

determining a preferable outcome measure based on the first and second sets of physiological data; and

altering the rate of blood fluid removal so that an indicator of tissue fluid volume and an indicator of blood fluid volume are within a pre-determined range of the preferable outcome measure.

2. The method of claim 1, wherein the outcome measure is any one of a degree of hypotension, a deviation from dry weight, or combinations thereof.

3. The method of claim 1, further comprising determining a ratio of the indicator of blood fluid volume to the indicator of tissue fluid volume;

and

altering the rate of blood fluid removal so that the ratio of the indicator of tissue fluid volume to the indicator of blood fluid volume is within a pre-determined range of the preferable outcome measure.

4. The method of claim 1, further comprising:

determining whether the indicator of tissue fluid volume or the indicator of blood fluid volume crosses a predetermined threshold during the blood fluid removal session.

5. The method of claim 4, wherein if the indicator of blood fluid volume or the indicator of tissue fluid volume crosses the predetermined threshold, altering the rate of blood fluid removal.

6. The method of claim 1, wherein the indicator of tissue fluid volume is tissue impedance.

7. The method of claim 1, wherein the indicator of blood fluid volume is a hematocrit level, or an indicator thereof.

8. The method of claim 7, wherein measuring the hematocrit level comprises measuring oxygenated hemoglobin concentration.

9. The method of claim 1, wherein one or both of the indicator of tissue fluid volume and the indicator of blood fluid volume are measured with one or more implantable sensors.

10. The method of claim 1, wherein the blood fluid removal session is carried out with an implantable blood fluid removal device.

11. The method of claim 1, wherein the blood fluid removal session is carried out with a wearable blood fluid removal device.

12. The method of claim 1, wherein if the indicator of tissue fluid volume or the indicator of blood fluid volume is outside of a pre-determined range, an alert is provided.

19. A system, comprising:

a blood fluid removal device comprising

(i) an inlet for receiving blood from a patient,

(ii) a first outlet for returning blood from the patient,

(iii) a medium for removing fluid and contaminants from the blood, the medium being positioned between the inlet and the first outlet,

(iv) a fluid rate removal controller; and

(v) a second outlet for flow of the removed fluid and contaminants;

a first sensor for monitoring an indicator of tissue fluid volume;

a second sensor for monitoring an indicator of blood fluid volume;

control electronics in operable communication with the sensor for monitoring an indicator of tissue fluid volume, the sensor for monitoring an indicator of blood fluid volume; and

the fluid rate removal controller,

wherein the control electronics are configured to carry out the method of claim 1.

20. The system of claim 19, wherein the medium for removal of fluid and contaminants from the blood comprises a filtration membrane.

21. The system of claim 19, wherein one or more components of the first sensor, the second sensor and the control electronics are housed within the blood fluid removal device.

13. A method carried out by a blood fluid removal system comprising:

initiating a blood fluid removal session of a patient;

monitoring an indicator of tissue fluid volume of the patient, or a portion thereof, during the blood fluid removal session;

monitoring an indicator of blood fluid volume of the patient during the blood fluid removal session;

determining whether the indicator of tissue fluid volume and the indicator of blood fluid volume are outside of a predetermined range; and

altering the rate that replacement fluid is added to the blood if the indicator of tissue fluid volume or the indicator of blood volume is determined to be outside of the predetermined range.

14. The method of claim 13, wherein the replacement fluid is added to the blood prior to fluid being removed from the blood.

15. The method of claim 13, wherein the replacement fluid is added to the blood after fluid being removed from the blood.

16. The method of claim 13, further comprising obtaining a ratio of the indicator of tissue fluid volume to the indicator of blood fluid volume;

determining whether the ratio of the indicator of tissue fluid volume to the indicator of blood fluid volume is outside of a predetermined range; and

altering the rate that the replacement fluid is added to the blood if the ratio of the indicator of tissue fluid volume to the indicator of blood fluid volume is outside of the predetermined range.

17. The method of claim 13, wherein if the indicator of tissue fluid volume or the indicator of blood fluid volume is outside of a pre-determined range, an alert is provided.

18. The method of claim 13, further comprising altering a rate of blood fluid removal if the indicator of tissue fluid volume or the indicator of blood volume is determined to be outside of the predetermined range.