Systems and methods providing a liquid-primed, single flow access chamber

• US 6,027,441 A
• Filed: 07/01/1997
• Issued: 02/22/2000
• Est. Priority Date: 07/01/1997
• Status: Expired due to Term

• Current Assignee: Baxter International Inc.
• Original Assignee: Baxter International Inc.
• Inventors: Cantu, Robert J, Min, Kyungyoon, Reitz, Douglas W
• Primary Examiner(s): Kim, John
• Application Number:
  US08/886,179
• Time in Patent Office: 966 Days
• Field of Search: 210/718, 210/739, 210/767, 210/97, 210/143, 210/218, 210/416.1, 210/782, 494/23, 494/5, 494/27, 494/37
• US Class Current: 494/37
• CPC Class Codes: A61M 1/362227 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36225 with blood pumping means or components thereof
• CPC Class Codes: A61M 1/362261 at least one cassette surface or portion thereof being flexible, e.g. the cassette having a rigid base portion with preformed channels and being covered with a foil
• 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 1/3693 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: B01D 21/262 by using a centrifuge
• CPC Class Codes: B01D 21/32 Density control of clear liquid or sediment, e.g. optical control ; Control of physical properties
• CPC Class Codes: B01D 21/34 Controlling the feed distribution; Controlling the liquid level ; Control of process parameters
• CPC Class Codes: B01D 2221/10 Separation devices for use in medical, pharmaceutical or laboratory applications, e.g. separating amalgam from dental treatment residues apparatus for dental treatment A61C17/065
• CPC Class Codes: B04B 2005/045 having annular separation channels
• CPC Class Codes: B04B 2009/143 by weight compensation with liquids
• CPC Class Codes: B04B 9/14 Balancing rotary bowls balancing per se G01M; Schrappers

Abstract

Blood processing systems and methods rotate a processing chamber on a rotating element. The processing chamber includes a first compartment and a second compartment. Blood is conveyed into the first compartment for centrifugal separation into components. A liquid free of blood occupies the second compartment to counter-balance the first compartment during rotation on the rotating element. In one embodiment, the second compartment is served by a single fluid flow access. Prior to use, the single access is coupled to tubing, through which a vacuum is drawn to remove air from the second compartment. While the vacuum exists, communication is opened between the tubing and a source of liquid. The vacuum draws the liquid into the second compartment through the single access, thereby priming the second compartment for use.

Claims

1. A blood processing system comprising

a processing chamber having a single fluid flow access, the processing chamber containing residual air,

tubing communicating with the single access,

a pump element in the tubing, and

a controller coupled to the pump element operative in a first mode to operate the pump element to draw a vacuum in the processing chamber to remove the residual air without introducing liquid into the processing chamber, the pump element being operative in a second mode to open communication between the tubing and a source of liquid after removal of the residual air and while the vacuum exists in the processing chamber, whereby the vacuum draws the liquid into the processing chamber to prime the processing chamber, and whereby the residual air is vented from the processing chamber prior to use.

2. A blood processing system according to claim 1

wherein, during the second mode, the controller commands the pump element to convey the liquid into the processing chamber while the vacuum also draws the liquid into the processing chamber.

3. A method of priming a container having a single fluid flow access, the container containing residual air, the method comprising the steps of

(i) coupling the single access to tubing which includes a pump element,

(ii) operating the pump element to draw a vacuum in the container and thereby remove the residual air from the container through the single access without introducing liquid into the container, and

(iii) after step (ii), opening communication between the tubing and a source of liquid while the vacuum exists in the container, whereby the vacuum draws the liquid into the container through the single access and thereby primes the container.

4. A method according to claim 3 wherein step (iii) includes operating the pump element to convey the liquid into the container through the single access while the vacuum also draws the liquid into the container through the single access.