HEMOFILTRATION SYSTEM AND METHOD BASED ON MONITORED PATIENT PARAMETERS

• US 20010045395A1
• Filed: 03/10/1997
• Published: 11/29/2001
• Est. Priority Date: 10/11/1991
• Status: Active Grant

• Current Assignee: Yuli Kitaevich
• Original Assignee: Yuli Kitaevich
• Inventors: HEMASILPIN, NAT, BISSLER, JOHN J., MCENERY, PAUL T., KITAEVICH, YULI, MARCHEVSKY, J. GABRIEL, BENZING, GEORGE III
• Granted Patent: US 6,471,872 B2
• Time in Patent Office: Days
• US Class Current: 210/739
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1611 Weight of the patient
• CPC Class Codes: A61M 1/1643 with weighing of fresh and used dialysis fluid
• 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 1/341 by measuring the filtrate rate or volume
• CPC Class Codes: A61M 1/3427 back through the membrane, e.g. by inverted trans-membrane pressure [TMP]
• CPC Class Codes: A61M 1/3451 the difference in weight between both ultra-filtrate and substitution reservoir being used as control signal
• CPC Class Codes: A61M 1/3607 Regulation parameters
• CPC Class Codes: A61M 1/3623 Means for actively controlling temperature of blood
• CPC Class Codes: A61M 2205/15 Detection of leaks
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 2205/3344 Measuring or controlling pressure at the body treatment site
• CPC Class Codes: A61M 2205/3393 by weighing the reservoir
• 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 2230/205 partial oxygen pressure (P-O2)
• CPC Class Codes: Y10S 210/929 Hemoultrafiltrate volume measurement or control processes

Abstract

A multipurpose hemofiltration system and method are disclosed for the removal of fluid and/or soluble waste from the blood of a patient. The system and method are equally applicable to adult, pediatric and neonatal patients. In one embodiment, the system continuously monitors the weight of infusate in a first reservoir and drained fluid in a second reservoir and compares those weights to corresponding predetermined computed weights. When necessary, the pumping rates of the infusate, drained fluid and blood are adjusted in order to achieve a preselected amount of fluid removal from the patient'"'"'s blood in a preselected time period. Application of this system and method provide repeatable and highly precise results. Alternatively, predetermined patient parameters can be monitored and the adjustment of pumping rates may be responsive to these monitored parameters. Suitable patient parameters are arterial pressure, central venous pressure, pulmonary arterial pressure, mean arterial pressure, capillary wedge pressure, systemic vascular resistance, cardiac output, mixed venous O₂ saturation, arterial O₂ saturation, blood pressure, heart rate, patient weight, and hematocrit.

Claims

1. Continuous hemofiltration system for removal of fluid from the blood of a patient, comprising:

a hemofilter;

a first pump for pumping blood from a patient through said hemofilter and back to he patient;

a first reservoir for maintaining a supply of infusate;

a first scale for monitoring the weight of the infusate and generating weight data signals correlated thereto;

a second pump for pumping the infusate from said first reservoir to said hemofilter;

a second reservoir for receiving drained fluid from said hemofilter;

a second scale for monitoring the weight of the drained fluid and generating weight data signals correlated thereto;

a third pump for pumping the drained fluid from said hemofilter to said second reservoir;

at least one monitor for monitoring a predetermined patient parameter and generating parameter data signals correlated thereto; and

a computer controller operably connected to said blood pump and to each of said second and third pumps, said first and second scales and said at least one patient parameter monitor;

said controller

receiving said weight data signals generated by said first and second scales and said parameter data signals generated by said at least one parameter monitor,

determining from said weight data signals the weight of infusate and drained fluid in said first and second reservoirs, respectively, at regular intervals

comparing those weights to corresponding predetermined computed weights,

determining from said parameter data signals the corresponding patient parameter data,

comparing the parameter data to corresponding predetermined data, and

generating control signals to adjust and thereby automatically adjusting the rates of pumping one or more of the infusate, drained fluid and blood while the pumps are pumping during hemofiltration so as to remove a preselected amount of fluid from the blood over a preselected time period.

2. A hemofiltration system according to

claim 1

wherein said monitored patient parameter is selected from the group consisting of arterial pressure, central venous pressure, pulmonary arterial pressure, mean arterial pressure, capillary wedge pressure, systemic vascular resistance, cardiac output, mixed venous O₂ saturation, arterial O₂ saturation, blood pressure, heart rate, patient weight, and hematocrit.

3. A hemofiltration system according to

claim 1

further comprising:

an interface with one or more infusion pumps supplying fluid to the patient, said controller receiving infusion data signals from the one or more infusion pumps.

4. Continuous hemofiltration system for removal of fluid from the blood of a patient, comprising:

a hemofilter;

a first pump for pumping blood through said hemofilter and back to the patient;

a supply of infusate;

a second pump for pumping the infusate to said hemofilter;

a receptacle for receiving drained fluid from said hemofilter;

a third pump for pumping the drained fluid from said hemofilter to said receptacle;

at least one monitor for monitoring a predetermined patient parameter and generating parameter data signals correlated thereto; and

a computer controller operably connected to said blood pump, said second and third pumps, and said at least one patient parameter monitor;

said controller

receiving said parameter data signals generated by said at least one parameter monitor,

determining from said parameter data signals the corresponding patient parameter data,

comparing the parameter data to corresponding predetermined data, and

generating control signals to adjust and thereby automatically adjusting the rates of pumping one or more of the infusate, drained fluid and blood while the respective pumps are pumping during hemofiltration so as to remove a preselected amount of fluid from the blood over a preselected time period.

5. A hemofiltration system according to

claim 4

wherein said monitored patient parameter selected from the group consisting of arterial pressure, central venous pressure, pulmonary arterial pressure, mean arterial pressure, capillary wedge pressure, systemic vascular resistance, cardiac output, mixed venous O₂ saturation, arterial O₂ saturation, blood pressure, heart rate, patient weight, and hematocrit.

6. Hemofiltration method for removal of fluid from the blood of a patient, comprising:

pumping blood from a patient through a hemofilter and back to the patient;

maintaining a supply of infusate in a first reservoir;

pumping the infusate to the hemofilter;

monitoring the weight of the infusate and generating weight data signals correlated thereto;

pumping drained fluid from the hemofilter into a second reservoir;

monitoring the weight of the drained fluid and generating weight data signals correlated thereto;

monitoring at least one predetermined patient parameter and generating parameter data signals correlated thereto; and

controlling the pumping rates of the blood, infusate and drained fluid by means of a programmed computer, said computer being responsive to the infusate and drained fluid weight data signals and to said parameter data signals,

said computer

receiving said weight data signals and said parameter data signals,

determining from said weight data signals, at regular intervals, the weight of infusate in the first reservoir and the weight of drained fluid in the second reservoir,

comparing those weights to corresponding predetermined computer weights,

determining from said parameter data signals the corresponding patient parameter data,

comparing the parameter data to corresponding predetermined data, and

generating control signals to adjust and thereby automatically adjusting the rates of pumping one or more of the infusate, drained fluid and blood while the respective pumps are pumping during hemofiltration so as to remove a preselected amount of fluid from the blood.

7. A hemofiltration method according to

claim 6

wherein said at least one monitored patient parameter is selected from the group consisting of arterial pressure, central venous pressure, pulmonary arterial pressure, mean arterial pressure, capillary wedge pressure, systemic vascular resistance, cardiac output, mixed venous O₂ saturation, arterial O₂ saturation, blood pressure, heart rate, patient weight, and hematocrit.

8. A hemofiltration method according to

claim 6

further comprising:

interfacing said computer controller with one or more infusion pumps supplying fluid to the patient, said computer receiving infusion data signals from the one or more infusion pumps.

9. The hemofiltration method of

claim 6

wherein said control signals adjust the pumping rates of one or more of the infusate, drained fluid and blood pumps such that the fluid removed from the patient'"'"'s blood is removed in a linear profile over time.

10. The hemofiltration method of

claim 6

wherein said control signals adjust the pumping rates of one or more of the infusate, drained fluid and blood pumps such that the fluid removed from the patient'"'"'s blood is removed in a non-linear profile over time.

11. Hemofiltration method for removal of fluid from the blood of a patient, comprising:

pumping blood from a patient through a hemofilter and back to the patient;

maintaining a supply of infusate;

pumping the infusate to the hemofilter;

pumping drained fluid from the hemofilter into a reservoir;

monitoring at least one predetermined patient parameter and generating parameter data signals correlated thereto; and

controlling the pumping rates of the blood, infusate and drained fluid by means of a programmed computer, said computer being responsive to said parameter data signals,

said computer

receiving said parameter data signals,

determining from said parameter data signals the corresponding patient parameter data,

comparing the parameter data to corresponding predetermined data, and

generating control signals to adjust and thereby automatically adjusting the rates of pumping one or more of the infusate, drained fluid and blood while the respective pumps are pumping during hemofiltration so as to remove a preselected amount of fluid from the blood.

12. A hemofiltration method according to

claim 11

wherein said at least one monitored patient parameter is selected from the group consisting of arterial pressure, central venous pressure, pulmonary arterial pressure, mean arterial pressure, capillary wedge pressure, systemic vascular resistance, cardiac output, mixed venous O₂ saturation, arterial O₂ saturation, blood pressure, heart rate and hematocrit.