Hydrophobic vent incorporated into cerebral spinal fluid drainage chamber

• US 20040092908A1
• Filed: 10/31/2003
• Published: 05/13/2004
• Est. Priority Date: 03/11/1999
• Status: Abandoned Application

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Vasek, Jeffrey A., Vaskelis, Paul Stanley, Harper, Derek Jonathan
• Application Number:
  US10/698,125
• Publication Number:
  US 20040092908A1
• Time in Patent Office: Days
• US Class Current: 604/540
• CPC Class Codes: A61M 27/006 Cerebrospinal drainage; Accessories therefor, e.g. valves

Abstract

The invention comprises several aspects which are each independently useful or which may be combined in a variety of combinations. One aspect of the invention is placing an atmospheric reference vent at or near the top of a rigid drip chamber for draining CSF from a patient. In the preferred embodiment, the vent is placed on the inside of the drip assembly, immediately next to the CSF. The vent, in another aspect of the invention, is made of a hydrophobic material. In the preferred embodiment, the hydrophilic material is expanded polytetrafluoroethylene (e-PTFE). In yet another aspect of the invention, the vent is made of a porous material having a pore size that allows air to readily pass through while preventing CSF from passing through. A preferred embodiment of this aspect includes making the vent of expanded polytetrafluoroethylene (e-PTFE) with a pore size ranging from about 0.22 μm to about 5.0 μm and more preferable a pore size of about 3 μm. With this pore size, the vent also preferably has a surface area ranging from about 0.5 cm² to about 5.0 cm².

Claims

1. A drip chamber in a cerebral spinal fluid (CSF) drainage system comprising:

a tube having an outer surface;

a vent in fluid communication with the tube, the vent having a filter made of a hydrophobic porous material wherein the pore size of the filter ranges from greater than 0.45 μ

m to about 5.0 μ

m; and

the vent having a surface area ranging from about 0.8 cm² to about 5.0 cm².

2. The drip chamber of claim 1 wherein the filter is flush with the outer surface of the volume reservoir.

3. The drip chamber of claim 2 wherein the vent is integral with the outer surface of the volume reservoir.

4. The drip chamber of claim 1 wherein the volume reservoir is rigid.