Barometric pressure sensor for use with implantable absolute pressure sensor

• US 6,152,885 A
• Filed: 04/30/1998
• Issued: 11/28/2000
• Est. Priority Date: 04/30/1998
• Status: Expired due to Fees

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Taepke, Robert T.
• Primary Examiner(s): O'Connor, Cary
• Assistant Examiner(s): WINGOOD, PAMELA LYNN
• Application Number:
  US09/070,366
• Time in Patent Office: 943 Days
• Field of Search: 600/585, 600/486, 600/561, 600/587
• US Class Current: 600/561
• CPC Class Codes: A61B 2560/0257 using atmospheric pressure
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/03 Detecting, measuring or recording fluid pressure within the body other than blood pressure, e.g. cerebral pressure; Measuring pressure in body tissues or organs A61B5/205 takes precedence

Abstract

A barometric pressure sensor for deriving reference pressure data for use in combination with absolute pressure data derived by an implantable medical device (IMD) is disclosed. The barometric pressure sensor is located in a sensing module adapted to be located with the patient'"'"'s body having a module housing enclosing an air chamber which encloses the barometric pressure sensor. An air vent extends through the module housing for venting the air chamber to atmospheric pressure outside the module housing. A protective vent cover extends across the air vent formed of a material capable of air passage and capable of inhibiting passage of moisture, liquids, and particulate contaminants through the air vent and into the air chamber. In one embodiment, the sensing module is adapted to be worn or carried by the patient and includes operating circuitry and a power supply for powering the barometric pressure sensor and periodically storing sensed atmospheric pressure values as reference pressure data. In another embodiment, the sensing module comprises a percutaneous access device which is adapted to be implanted in the skin and subcutaneous tissue layer of the patient and includes the protective vent cover extending across the air vent formed in the percutaneous access device. The percutaneous access device is coupled with the barometric pressure sensor to provide for an air chamber extending between the protective vent cover and the barometric pressure sensor. The barometric pressure sensor is preferably enclosed within an air chamber of the implantable medical device, and a catheter extends between the air chamber of the implantable medical device and the percutaneous access device.

Claims

1. A system for measuring barometric pressure for use in generating reference pressure values in conjunction with measurement of absolute pressure values within a patient'"'"'s body comprising:

a barometric pressure sensing module adapted to be located with the patient'"'"'s body having a module housing enclosing an air chamber, wherein the module housing is adapted to be implanted in the patient'"'"'s skin and subcutaneous tissue layer;

a percutaneous access device coupled to the barometric pressure sensing module to expose the air chamber to the atmosphere outside the patient'"'"'s body;

a barometric pressure sensor within the air chamber for generating reference pressure values representing the ambient air pressure in the air chamber; and

a protective vent cover extending over the air vent formed of a material capable of air passage and capable of inhibiting passage of moisture, liquids, and particulate contaminants through the air vent and into the air chamber.

4. The system of claim 1, wherein the protective vent cover is formed of a fabric material that allows passage of air and water vapor.

2. A system for measuring barometric pressure for use in generating reference pressure values in conjunction with measurement of absolute pressure values within a patient'"'"'s body comprising:

a barometric pressure sensing module adapted to be located with the patient'"'"'s body having a module housing enclosing an air chamber;

a barometric pressure sensor within the air chamber for generating reference pressure values representing the ambient air pressure in the air chamber;

an air vent extending through the module housing for venting the air chamber to atmospheric pressure outside the module housing; and

a protective vent cover extending over the air vent formed of a material capable of air passage and capable of inhibiting passage of moisture, liquids and particulate contaminants through the air vent and into the air chamber,

wherein the air vent is tubular in cross-section and at least one baffle is located within the air vent between an exterior air vent opening and the protective vent cover to block entrance of objects capable of penetrating the protective vent cover.

3. The system of claim 2, wherein the protective vent cover is formed of a fabric material that allows passage of air and water vapor.