Diaphragm pressure pod for medical fluids

• US 8,491,518 B2
• Filed: 11/18/2011
• Issued: 07/23/2013
• Est. Priority Date: 11/09/2005
• Status: Active Grant

• Current Assignee: B Braun Medical Incorporated (B. Braun Holding GmbH & Co. KG)
• Original Assignee: Nxstage Medical Incorporated (Fresenius Medical Care AG)
• Inventors: Schnell, William J., Bell, David, Wilson, Karen, Utterberg, David S.
• Primary Examiner(s): DEAK, LESLIE R
• Application Number:
  US13/299,868
• Publication Number:
  US 20120130338A1
• Time in Patent Office: 613 Days
• Field of Search: 604/4.01, 604/6.09, 604/6.11, 604/6.16, 604 65- 67, 210/645, 210/739, 210/741
• US Class Current: 604/6.16
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/3627 Degassing devices; Buffer reservoirs; Drip chambers; Blood filters
• 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 1/3655 Arterio-venous shunts or fistulae
• CPC Class Codes: A61M 39/00 Tubes, tube connectors, tube couplings, valves, access sites or the like, specially adapted for medical use for respiratory devices, e.g. tracheal tubes A61M16/00; artificial heart valves A61F2/24
• CPC Class Codes: F16L 29/005 joints with cut-off devices which can be perforated cut-off devices with a breakable closure member in general F16K13/04
• CPC Class Codes: Y10T 137/85978 With pump

Abstract

A tubular medical fluid flow set comprises a pressure sensing chamber connected in flow-through relation to fluid flow tubing of the set. The pressure sensing chamber defines a movable, flexible, impermeable diaphragm dividing the chamber into two separate compartments. The fluid flow tubing communicates with one of the compartments and is isolated from the other of the compartments. A port is carried on the chamber, the port having a seal therein, and communicating with the other of the compartments. Thus, the other of the compartments is hermetically sealed until the port is opened for connection with a pressure measuring device, to keep the flexible diaphragm in a desired, initial position prior to opening of the seal.

Claims

1. The method of rinsing blood from an extracorporeal blood flow tube and returning it to the patient after an extracorporeal blood flow procedure, said blood flow tubing connected to a chamber having a flexible diaphragm defining a blood holding volume, said diaphragm being sealingly mounted within said chamber, which method comprises:

pressurizing said chamber to move said diaphragm to cause the blood holding volume of said chamber to be substantially minimized, without blocking flow through said blood flow tube and chamber; and

causing aqueous solution to pass into said tube and chamber to replace said blood, while returning said blood to the patient.

2. The method of claim 1 in which said chamber was previously used to sense subatmospheric blood pressure in said blood flow tube through a length of pressure tubing connected to said chamber, wherein the diaphragm was initially positioned to essentially maximize the blood holding volume in said chamber.