Pressure reference assemblies for body fluid drainage systems and associated methods

Patent metadata

Field	Value
Publication number	US-10413710-B2
Application number	US-201515111459-A
Country	US
Kind code	B2
Filing date	Jan 16, 2015
Priority date	Jan 16, 2014
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

Drainage systems for excess body fluids and associated methods are disclosed herein. A drainage system in accordance with an embodiment of the present technology can include, for example, a drainage catheter, a first reference line, a second reference line, and a pressure sensor assembly. The catheter can include a flexible interface member and an inlet can be placed in fluid communication with a site of excess body fluid within a patient. A first flexible region of the first reference line can be in pressure communication with the flexible interface member, and a second flexible region of the second reference line can be in pressure communication with the surrounding atmosphere. The pressure sensor assembly can be spaced apart from the flexible regions, and measure the pressures of the first and second reference lines. This information can be used to determine the pressure at the site of excess body fluid.

First claim

We claim:

1. A pressure reference assembly for a body fluid drainage system, the pressure reference assembly comprising:
a first reference line having a first portion and a second portion opposite the first portion, wherein the first portion of the first reference line has a first flexible region configured to sense pressure;
a second reference line having a first portion and a second portion opposite the first portion, wherein the first portion of the second reference line has a second flexible region configured to be in pressure communication with atmospheric pressure, and wherein the first and second flexible regions are configured to be positioned at a first location and the second portions of the first and second reference lines are configured to be positioned at a second location spaced apart from the first location; and
a pressure sensor assembly at the second portions of the first and second reference lines, wherein the pressure sensor assembly is configured to measure pressure and/or force at the second portions of the first and second reference lines.

2. The pressure reference assembly of claim 1 , wherein the first and second reference lines are filled with a fluid.

3. The pressure reference assembly of claim 1 , wherein the first flexible region of the first reference line is configured to be in pressure communication with a drainage catheter and to sense pressure within the drainage catheter.

4. The pressure reference assembly of claim 1 , wherein the first flexible region of the first reference line is configured to be in pressure communication with atmospheric pressure.

5. The pressure reference assembly of claim 1 , wherein the pressure sensor assembly comprises:
a first pressure sensor at the second end portion of the first reference line, wherein the first pressure sensor is configured to measure pressure at the second end portion of the first reference line; and
a second pressure sensor at the second end portion of the second reference line, wherein the second pressure sensor is configured to measure pressure at the second end portion of the second reference line.

6. The pressure reference assembly of claim 5 , wherein the first flexible region of the first reference line is configured to be in pressure communication with a drainage catheter and to sense pressure within the drainage catheter, and further comprising a processing device operably coupled to the first and second pressure sensors, wherein the processing device is configured to determine pressure at the drainage catheter by subtracting a second pressure measurement taken by the second pressure sensor from a first pressure measurement taken by the first pressure sensor.

7. The pressure reference assembly of claim 1 , wherein the first end portions of the first and second reference lines are configured to be positioned near lateral ventricles of a patient's head, and wherein the second location is spaced apart from the patient's head.

8. The pressure reference assembly of claim 7 , wherein the first flexible region of the first reference line is configured to be in pressure communication with a drainage catheter and to sense pressure within the drainage catheter, and additionally comprising a processing device operably coupled to the pressure sensor assembly and configured to determine intracranial pressure based on a difference is pressure and/or force at the second portions of the first and second reference lines.

9. A body fluid drainage system, comprising a pressure reference assembly in combination with a drainage catheter, wherein:
the drainage catheter has a proximal portion and a distal portion, and wherein the proximal portion comprises an inlet configured to be in fluid communication with a site of excess body fluid within a patient; and the pressure reference assembly comprises:
a first reference line having a first portion and a second portion opposite the first portion, wherein the first portion of the first reference line has a first flexible region configured to sense pressure;
a second reference line having a first portion and a second portion opposite the first portion, wherein the first portion of the second reference line has a second flexible region configured to be in pressure communication with atmospheric pressure, wherein the second portions of the first and second reference lines are configured to be positioned at a second location spaced apart from the first and second flexible regions and; and
a pressure sensor assembly at the second portions of the first and second reference lines, wherein the pressure sensor assembly is configured to measure pressure and/or force at the second portions of the first and second reference lines.

10. The body fluid drainage system of claim 9 , wherein the first and second reference lines are filled with a reference fluid.

11. The body fluid drainage system of claim 9 , wherein the first and second flexible regions each comprise a flexible membrane made of an ether- and/or ester-based material.

12. The body fluid drainage system of claim 9 , wherein the drainage catheter comprises a flexible interface member positioned distally with respect to the inlet and the first flexible region of the first reference line is configured to be in pressure communication with the flexible interface member of the drainage catheter.

13. The body fluid drainage system of claim 9 , wherein the first flexible region of the first reference line is configured to be in pressure communication with atmospheric pressure.

14. The body fluid drainage system of claim 13 , wherein the site of excess body fluid defines a point along a reference axis that extends through the site of excess body fluid; the first flexible region of the first reference line is configured to be positioned at a first location along the reference axis to one side of the inlet of the drainage catheter; and the second flexible region of the second reference line is configured to be positioned at a second location along the reference axis to a side of the inlet of the drainage catheter opposite the first flexible region.

15. The body fluid drainage system of claim 14 , wherein the reference axis extends through lateral ventricles in a head of the patient, and wherein the first end portion of the first reference line is configured to be positioned on a first side of the head and the first end portion of the second reference line is configured to be positioned on a second side of the head opposite the first side.

16. The body fluid drainage system of claim 9 , wherein the drainage catheter comprises a flexible interface member positioned distally with respect to the inlet and the flexible interface member and the first flexible region of the first reference line are attached together.

17. The body fluid drainage system of claim 9 , wherein the drainage catheter comprises a flexible interface member positioned distally with respect to the inlet, and the flexible interface member and the first flexible region of the first reference line are positioned within a sealed compartment and are maintained in contact via a vacuum in the sealed compartment.

18. The body fluid drainage system of claim 9 , wherein the drainage catheter comprises a flexible interface member positioned distally with respect to the inlet and the flexible interface member of the drainage catheter is outwardly biased.

19. The body fluid drainage system of claim 9 , wherein the pressure sensor assembly is configured to measure intracranial pressure.

20. The body fluid drainage system of

Assignees

• Univ Washington Through Its Center For Commercialization
• Aqueduct Neurosciences Inc
• Univ Washington

Inventors

• Lutz Barry
• Browd Samuel R
• Clement Thomas
• Cran Brian
• Relethford Joel

Classifications

• A61M2205/3331

  Pressure; Flow · CPC title

• A61M27/006 Primary

  Cerebrospinal drainage; Accessories therefor, e.g. valves · CPC title

• A61B5/03

  Measuring fluid pressure within the body other than blood pressure, e.g. cerebral pressure {; Measuring pressure in body tissues or organs (determining bladder or urethral pressure A61B5/205)} · CPC title

• A61B5/031

  Intracranial pressure · CPC title