Extracorporeal Blood Processing Methods With Multiple Alarm Levels

• US 20070004997A1
• Filed: 09/08/2006
• Published: 01/04/2007
• Est. Priority Date: 12/22/1999
• Status: Active Grant

• Current Assignee: Terumo BCT, Inc. (Terumo Corporation)
• Original Assignee: Gambro, Inc. (DaVita Incorporated)
• Inventors: Felt, Thomas, Bainbridge, Marlene
• Granted Patent: US 7,513,882 B2
• Time in Patent Office: Days
• US Class Current: 604/6.10
• CPC Class Codes: A61M 1/0209 Multiple bag systems for separating or storing blood components
• CPC Class Codes: A61M 1/30 Single needle dialysis ; Reciprocating systems, alternately withdrawing blood from and returning it to the patient, e.g. single-lumen-needle dialysis or single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/303 having a reservoir for treated blood to be returned
• CPC Class Codes: A61M 1/308 Volume control, e.g. with open or flexible containers, by counting the number of pump revolutions, weighing
• CPC Class Codes: A61M 1/3496 Plasmapheresis; Leucopheresis; Lymphopheresis A61M1/3472 takes precedence
• CPC Class Codes: A61M 1/36 Other treatment of blood in a by-pass of the natural circulatory system, e.g. temperature adaptation, irradiation ; Extra-corporeal blood circuits
• CPC Class Codes: A61M 1/36222 Details related to the interface between cassette and machine
• CPC Class Codes: A61M 1/36224 with sensing means or components thereof
• CPC Class Codes: A61M 1/36225 with blood pumping means or components thereof
• CPC Class Codes: A61M 1/36226 Constructional details of cassettes, e.g. specific details on material or shape
• CPC Class Codes: A61M 1/362262 Details of incorporated reservoirs
• CPC Class Codes: A61M 1/362263 Details of incorporated filters
• CPC Class Codes: A61M 1/362265 Details of valves
• CPC Class Codes: A61M 1/362266 Means for adding solutions or substances to the blood
• CPC Class Codes: A61M 1/3639 Blood pressure control, pressure transducers specially adapted therefor
• CPC Class Codes: A61M 1/3641 Pressure isolators
• CPC Class Codes: A61M 1/3656 Monitoring patency or flow at connection sites; Detecting disconnections
• CPC Class Codes: A61M 1/3693 using separation based on different densities of components, e.g. centrifuging
• CPC Class Codes: A61M 1/3696 with means for adding or withdrawing liquid substances during the centrifugation, e.g. continuous centrifugation
• CPC Class Codes: A61M 2205/123 with incorporated reservoirs
• CPC Class Codes: A61M 2205/17 : with redundant control systems
• CPC Class Codes: A61M 2205/18 : with alarm
• CPC Class Codes: A61M 2205/3331 : Pressure; Flow
• CPC Class Codes: A61M 2205/3334 : Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/50 : with microprocessors or computers
• CPC Class Codes: A61M 37/00 : Other apparatus for introducing media into the body for reproduction or fertilisation A61B17/425; apparatus for iontophoresis or cataphoresis A61N1/30; Percutany, i.e. introducing medicines into the body by diffusion through the skin salt baths A61H33/04

Abstract

This invention provides a method for controlling a fluid separation system, preferably a blood apheresis system having a leukocyte reduction chamber. The method utilizes a three-level alarm system. A first-level alarm condition is triggered in response to a pressure drop in the system to less than or equal to a specified system pressure and pauses fluid flow in at least a portion of the system. A second-level alarm condition is triggered in response to a specified number of said pressure drops within a specified period and reduces the flow rate of the fluid in the system. The alarm conditions may also trigger a visible and/or audible alarm. These alarm levels permit flow through the leukocyte reduction chamber to continue when the pressure drop is caused by a non-serious, self-resolving or easily-correctable condition such as misalignment of system components.

Claims

1. A method for controlling an apheresis system comprising:

triggering a first alarm condition in response to a specified pressure drop to less than or equal to a specified pressure in the system, said first alarm condition comprising pausing fluid flow in at least a portion of said system for a specified delay time;

if plasma and platelet collection is incomplete, triggering a second-level alarm condition in response to a specified number of said specified pressure drops within a specified period, said second alarm condition comprising reducing flow rate of fluid in said system;

if plasma and platelet collection is complete, triggering a third-level alarm condition in response to a selected number of said selected pressure drops within a specified period, said third-level alarm condition comprising stopping all pumps.

2. The method of claim 1 further comprising

shutting down said system during said third alarm condition or returning said system to normal operation.

3. The method of claim 2 wherein returning said system to normal operation comprises reducing a blood flow rate.

4. The method of claim 1 further comprising

if said specified pressure drop re-occurs during said second alarm condition, triggering said third-level alarm condition.

5. The method of claim 4 further comprising

shutting down said system during said third alarm condition or returning said system to normal operation.

6. The method of claim 5 wherein returning said system to normal operation comprises reducing a blood flow rate.