Blood Volume Controller During Fluid Removal

• US 20070055198A1
• Filed: 07/27/2006
• Published: 03/08/2007
• Est. Priority Date: 07/28/2005
• Status: Active Grant

• Current Assignee: Gambro Lundia AB (Baxter International Inc.)
• Original Assignee: CHF Solutions, Inc.
• Inventors: O'Mahony, John, Sobotka, Paul, Rychlick, Edward
• Granted Patent: US 8,556,846 B2
• Time in Patent Office: Days
• US Class Current: 604/67
• CPC Class Codes: A61M 2230/207 hematocrit
• CPC Class Codes: A61M 5/14212 Pumping with an aspiration and an expulsion action
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

A blood volume control method has been developed including: monitoring a condition of a patient (such as hematocrit (Hct)), wherein the condition is indicative of blood volume in the patient; automatically determining that the condition indicates a low blood volume in the patient; automatically infusing an infusion solution into the patient in response to the determination of a low blood volume, and automatically adjusting the infusion to maintain the monitored condition at a predetermined value.

Claims

1. A blood volume control method comprising:

monitoring an actual condition of a patient, wherein the condition is indicative of blood volume in the patient;

comparing the actual condition to a desired value for the condition and determining a difference between the actual condition and desired value;

if the difference exceeds a predetermined value, automatically infusing an infusion solution into the patient in response to the determination of a low blood volume.

2. A blood volume control method as in claim 1 wherein the condition is hematocrit (Hct) of the blood of the patient.

3. A blood volume control method as in claim 1 wherein the condition is monitored by a transcutaneous hematocrit (Hct) sensor.

4. A blood volume control method as in claim 1 wherein the condition is monitored by a sensor sensing a translucent property of blood in a surface peripheral venous system of the patient.

5. A blood volume control method as in claim 1 wherein an infusion pump causes the infusion solution to flow from a solution container, through a tube to a catheter inserted in a vein of the patient.

6. A blood volume control method as in claim 1 further comprising at least temporarily ceasing the infusion after sensing the condition above a threshold level.

7. A blood volume control method as in claim 1 further comprising monitoring urine output of the patient and limiting infusion of the infusion solution to be less than a threshold level based on urine output.

8. A blood volume control method as in claim 1 wherein the rate is a variable rate adjusted to maintain a constant condition level.

9. A blood volume control system comprising:

a Hct sensor connected to a patient, measuring a Hct of blood in the patient;

an infusion pump connectable to fluid tube for providing fluid communication of a source of an infusion solution to a venous system of a patient via a catheter;

a controller receiving a signal from the Hct sensor, wherein the signal is indicative of the Hct and generating a control signal for the infusion pump, wherein the controller actuates the pump in response to an indication from the Hct sensor of a low Hct.

10. A blood volume control system as in claim 9 wherein the controller actuates the pump to infuse the infusion solution into the patient at a rate required to main a predefined Hct target.

11. A blood volume control system as in claim 9 wherein the Hct sensor senses a translucent property of blood in a surface peripheral venous system of the patient.

12. A blood volume control method as in claim 9 wherein the infusion pump causes the infusion solution to flow from a solution container, through a tube to a catheter inserted in a vein of the patient.

13. A method for controlling a patients Hct using a Hct sensor and an infusion pump, said method comprising:

sensing an actual Hct of blood in a vascular system of a patient;

determining a difference between the actual Hct and a threshold Hct;

automatically adjusting an infusion of an infusion solution to the patient to reduce the difference below a predetermined value.

14. A method as in claim 13 further comprising adjusting a rate of infusion from a first rated to a slower rate above a zero rate to reduce the difference.

15. A method of preventing vascular volume depletion using a Hct sensor and an infusion pump, said method comprising:

determining a current Hct of blood in a patient;

comparing the current Hct to a desired Hct value;

infusing an infusion solution to a venous system of the patient if the current Hct is below the desired Hct target value, and

infusing the infusion solution into the patient at a rate determined to maintain the desired Hct target value.

16. A method as in claim 15 wherein the current Hct is monitored by a sensor sensing a translucent property of blood in a surface peripheral venous system of the patient.

17. A method as in claim 15 wherein the infusion pump causes the infusion solution to flow from a solution container, through a tube to a catheter inserted in a vein of the patient.

18. A method as in claim 15 further comprising at least temporarily ceasing the infusion after sensing the condition above a threshold level.

19. A method as in claim 15 wherein the rate is a variable rate adjusted to maintain a constant vascular volume in the patient.

20. A method of preventing vascular volume depletion during diuretic delivery using a Hct sensor, an infusion solution, an infusion pump and catheter, said method comprising:

sensing an indicator of a current Hct of blood in a patient;

comparing the indicator to a target,

an infusion pump connected to the vascular system of the patient, and

infusing a volume expansion solution into the vascular space at a rate required to maintain the target.

21. A method as in claim 20 wherein the infusion pump causes the infusion solution to flow from a solution container, through a tube to a catheter inserted in a vein of the patient.

22. A method as in claim 20 further comprising at least temporarily ceasing the infusion when a predetermined difference occurs between the indicator and the target.

23. A method as in claim 20 wherein the rate is a variable rate adjusted to maintain a constant vascular volume in the patient.

24. A method as in claim 20 further comprising adjusting a rate of infusion from a first rated to a slower rate above a zero rate to reduce a difference between the indicator and the target.

25. A method as in claim 20 wherein the current Hct is monitored by a sensor sensing a translucent property of blood in a surface peripheral venous system of the patient and the indicator is an output signal of the sensor.

26. A method as in claim 20 further comprising at least reducing the infusion if a urine output of the patient is excessive.

27. A method as in claim 20 further comprising at least reducing the infusion if a urine output exceeds a predetermined condition.