Portable pressure transducer, pneumotach for use therewith, and associated methods

• US 6,691,579 B2
• Filed: 05/07/2002
• Issued: 02/17/2004
• Est. Priority Date: 05/07/2001
• Status: Expired due to Term

• Current Assignee: RIC INVESTMENTS LLC (Respironics Incorporated)
• Original Assignee: Respironics Incorporated
• Inventors: Orr, Joseph A., Kofoed, Scott A., Durst, Kevin
• Primary Examiner(s): Lefkowitz, Edward
• Assistant Examiner(s): JENKINS, JERMAINE L
• Application Number:
  US10/139,920
• Publication Number:
  US 20020162397A1
• Time in Patent Office: 651 Days
• Field of Search: 737/00, 731/173, 738/612.4, 738/61, 737/56, 128/716, 128/204.23, 128/205.23, 128/200.24, 600/529, 600/532, 600/538
• US Class Current: 73/700
• CPC Class Codes: A61B 5/087 Measuring breath flow
• CPC Class Codes: G01L 13/00 Devices or apparatus for measuring differences of two or more fluid pressure values

Abstract

A system for sensing respiratory pressure includes a portable pressure transducer configured to be carried by or proximate to a respiratory conduit, such as a breathing circuit or a nasal canula. The portable pressure transducer may removably couple with a pneumotach, in the form of an airway adapter, disposed along the respiratory conduit. The pneumotach may include two pressure ports positioned at opposite sides of an obstruction, which partially blocks flow through a primary conduit of the pneumotach. Corresponding sample conduits of the portable pressure transducer removably couple with the pressure ports. The pressure ports may have sealing elements which are configured to seal against piercing members of the sample conduits upon introduction of the piercing members therethrough. Upon removal of the piercing members, the sealing elements substantially reseal. Methods for using the system are also disclosed.

Claims

1. A respiratory pressure sensing system, comprising:

(a) a pneumotach configured to be positioned along a respiratory conduit, the pneumotach comprising;

(1) a pneumotach housing,

(2) a primary conduit defined in the pneumotach housing,

(3) a first pressure port and a second port, wherein the first pressure port and the second pressure port are defined in the pneumotach housing in fluid communication with the primary conduit, and

(4) a pressure transducer coupling portion disposed on the pneumotach housing; and

(b) a pressure transducer configured to be removably coupled with the pneumotach, the pressure transducer comprising;

(1) a pressure transducer housing,

(2) a pneumotach coupling portion disposed on the pressure transducer housing and configured to selectively and removably engage the pressure transducer coupling portion to attach the pressure transducer housing to the pneumotach housing,

(3) a first pressure sensor disposed in the housing, and

(4) a first sample conduit and a second sample conduit, wherein the first sample conduit and the second sample conduit each includes a first portion disposed in the housing and coupled to the first pressure sensor, and a second portion adapted to cooperate with an associated pressure port of the pneumotach so as to communicate a respiratory sample from the primary conduit of the pneumotach to the first pressure sensor responsive to the pressure transducer housing being coupled to the pneumotach housing.

2. The system of claim 1, wherein the pneumotach further includes a flow restricting element disposed in at least a portion of the primary conduit, and wherein the first and the second pressure ports are positioned on opposite sides of the flow restricting element.

3. The system of claim 1, wherein the second portion of the first conduit and the second portion of the second conduit is defined by a portion of the housing.

4. The system of claim 3, wherein the portion of the housing defining the second portion of the first conduit and defining the second portion of the second conduit each includes a piercing portion.

5. The system of claim 1, wherein the first pressure sensor comprises a differential pressure sensor in communication with the first and the second sample conduits.

6. The system of claim 5, wherein the pressure transducer further includes a second pressure sensor having a first portion in communication with at least one of the first and the second pressure ports and a second portion in communication with an environment external to the pressure transducer.

7. The system of claim 1, wherein the first pressure port includes a first opening and the second pressure port includes a second opening, and wherein the pneumotach further includes a first sealing member covering the first opening and a second sealing member covering the second opening.

8. The system of claim 1, wherein the first sampling conduit includes a first opening and the second sampling conduit includes a second opening, and wherein the pressure transducer further comprises a first sealing portion covering the first opening and a second sealing portion covering the second opening.

9. The system of claim 8, wherein the first sealing portion and the second sealing portion are defined by a common sealing member.

10. The system of claim 1, wherein the second portion of the first sample conduit comprises a first piercing member, and wherein the second portion of the second sample conduit comprises a second piercing member.

11. The system of claim 1, wherein the pneumotach further comprises a first hollow protruding portion extending from the pneumotach housing at the first pressure port and a second hollow protruding portion extending from the pneumotach housing at the second pressure port.

12. The system of claim 11, wherein the first hollow protruding portion includes a first piercing portion disposed at an end thereof, and wherein the second hollow protruding portion includes a second piercing portion disposed at an end thereof.

13. The system of claim 1, further comprising a first valve disposed in the first sample conduit and a second valve disposed in the second sample conduit.

14. The system of claim 1, further comprising a monitor in communication with the first pressure sensor, wherein the monitor is programmed to calculate a respiratory pressure parameter, a respiratory flow parameter, a respiratory volume parameter, a blood gas parameter, a blood flow parameter, or any combination thereof based at least partially on a signal from the first pressure sensor.

15. A method for monitoring a parameter associated with respiration of a patient, comprising:

(a) providing a respiratory circuit in fluid communication with an airway of a patient;

(b) providing a pneumotach at a first location along the respiratory conduit, the pneumotach comprising;

(1) a pneumotach housing,

(2) a primary conduit defined in the pneumotach housing,

(3) a first pressure port and a second port, wherein the first pressure port and the second pressure port are defined in the pneumotach housing in fluid communication with the primary conduit, and

(4) a pressure transducer coupling portion disposed on the pneumotach housing; and

(c) providing a pressure transducer comprising;

(1) a pressure transducer housing,

(2) a pneumotach coupling portion disposed on the pressure transducer housing and configured to selectively and removably engage the pressure transducer coupling portion to attach the pressure transducer housing to the pneumotach housing,

(3) a first pressure sensor disposed in the housing, and

(4) a first sample conduit and a second sample conduit, wherein the first sample conduit and the second sample conduit each includes a first portion disposed in the housing and coupled to the first pressure sensor, and a second portion adapted to cooperate with an associated pressure port of the pneumotach so as to communicate a respiratory sample from the primary conduit of the pneumotach to the first pressure sensor responsive to the pressure transducer housing being coupled to the pneumotach housing; and

(d) attaching the pressure transducer to the pneumotach by engaging the pneumotach coupling portion with the pressure transducer coupling portion.

16. The method of claim 15, wherein attaching the pressure transducer to the pneumotach includes providing a fluid communication between the first pressure port and the first sample conduit and providing a fluid communication between the second pressure port and the second sample conduit.

17. The method of claim 16, wherein providing a fluid communication between the first pressure port and the first sample conduit includes piercing a first seal disposed on the first pressure port with the second portion of the first sample conduit, and wherein providing a fluid communication between the second pressure port and the second sample conduit includes piercing a second seal disposed on the second pressure port with the second portion of the second sample conduit.

18. The method of claim 16, wherein providing a fluid communication between the first pressure port and the first sample conduit includes piercing a first seal disposed over the second portion of the first sample conduit with a first hollow protruding portion extending from the pneumotach housing at the first pressure port, and wherein providing a fluid communication between the second pressure port and the second sample conduit includes piercing a second seal disposed over the second portion of the second sample conduit with a second hollow protruding portion extending from the pneumotach housing at the second pressure port.

19. The method of claim 15, further comprising (e) disassembling the pressure transducer from the pneumotach.