Pressure transducer assembly

Abstract

A pressure transducer assembly is disclosed for directly monitoring pressure in a fluid which flows through the assembly. The assembly includes a housing defining a chamber therewithin and having an inlet port and an outlet port in fluid-flow communication with the chamber. An electrically insulated body element is sealed within the chamber dividing the chamber into a first chamber and a second chamber. The first chamber is in fluid-flow communication with the inlet and outlet ports. The second chamber is separated from the first chamber by a fluid-tight seal such that any fluid present in the first chamber cannot enter the second chamber. A pressure transducer sensor is secured in the insulated body and exposed to the first chamber such that the sensor can determine the pressure in a fluid in the first chamber and convert the pressure into electric impulses. The sensor is separated from the fluid in the first chamber by an insulating medium across which fluid pressure can be determined. Connected to the sensor are electrical conductors which extend through the insulated body and into the second chamber. The second chamber provides an engagement site for an electrical connector which can interconnect with the electrical conductors and provide an electrical path through which the electric impulses generated by the sensor can be transferred to a monitor.

Description

BACKGROUND OF THE INVENTION

The pressure transducer assembly herein can be used in any fluid line for which the fluid pressure within the line is to be determined. The pressure transducer assembly herein has particular utility for the invasive monitoring of blood pressure. In a particular application, the pressure transducer assembly provides a disposable pressure transducer assembly which can be used for a single patient use and then discarded.

Invasive blood pressure monitoring as a system which provides an accurate method for monitoring the blood pressure of a patient. Frequently, invasive blood pressure monitoring is performed for critically infirmed patients. Invasive blood pressure monitoring is also performed during critical surgeries and on patients in intensive care units and critical care units. Invasive blood pressure monitoring is gaining acceptance in conjunction with the care and treatment of cardiac obtined obtained and with the communication of the fluid in the pressure transducer assembly and the patient's circulatory system, any pressure within the circulatory system is correspondingly observed in the fluid present in the first chamber of the pressure transducer assembly. The silicon pressure sensor thereby observes the pressure in the fluid and transforms such sensed pressure into electrical impulses which flow along the wiring 40 to the display unit 56 wherein the pressure readings are displayed for the benefit of the attendant.

Claims

1. A pressure transducer assembly for monitoring pressure in a fluid comprising:

a housing defining a chamber and having an inlet port and an outlet port in fluid-flow communication with the chamber;

an insulated body sealed within the chamber which forms separate first and second chambers within the housing with the first chamber in fluid-flow communication with the inlet port and outlet port;

a pressure transducer means secured in the insulated body and exposed to the first chamber for determining and converting fluid pressure within a fluid in the first chamber into electrical impulses;

a fluid pressure responsive media covering the pressure transducer means which is electrically non-conductive and which separates the pressure transducer means from any fluid present in the first chamber;

electrical conducting means connected to the pressure transducer means and extending through the insulated body and into the second chamber for providing electrical connection between the pressure transducer means in the first chamber and the second chamber; and

engagement means on the housing for providing a connection locus on the housing for electrical wiring which can be interconnected with the electrical conducting means.

2. A pressure transducer assembly as required in claim 1 wherein the fluid pressure responsive media comprises silicone elastomer.

3. A pressure transducer assembly as recited in claim 1 further comprising tubing connecting means on the inlet and outlet ports for connecting tubing to the housing.

4. A pressure transducer assembly as recited in claim 1 wherein the electrical conducting means comprises a plurality of electrical conducting metal pins electrically interconnected to the pressure transducer means to transfer power to the pressure transducer means and to transfer away electrical impulse signals corresponding to determined pressures.

5. A pressure transducer assembly as recited in claim 1 wherein the insulated body sealed within the chamber comprises a polysulfone body.

6. A pressure transducer assembly as recited in claim 1 wherein the pressure transducer means comprises a silicon pressure transducer with a single piezoresistive element.

7. A pressure transducer assembly as recited in claim 6 wherein the pressure transducer means comprises a monolithic silicon pressure sensor employing a four-terminal resistive element formed in a monocrystalline silicon diaphragm.

8. A pressure transducer assembly as recited in claim 1 wherein the pressure transducer means monitors fluid pressure within the first chamber in the range from about -50 mmHg to +300 mmHg.

9. A pressure transducer assembly as recited in claim 1 further comprising a clear lens means on the housing extending over the first chamber for viewing fluid and bubbles in the fluid within the first chamber.

10. A pressure transducer assembly as recited in claim 9 wherein the clear lens means comprises a clear dome portion on the housing extending over at least a portion of the first chamber.

11. A pressure transducer assembly as recited in claim 1 wherein the housing comprises a biocompatible polymeric material.

12. A pressure transducer assembly as recited in claim 11 wherein the biocompatible polymeric material is selected from the group consisting of polycarbonate, polypropylene, polyethylene and polysulfone.

13. A pressure transducer assembly as recited in claim 1 further comprising vent means on the housing and on the insulated body for providing exposure to the atmosphere for the pressure transducer means.

14. A pressure transducer assembly as recited in claim 13 wherein the vent means comprises an opening extending through the housing into the second chamber and aligned with an opening extending through the insulated body and leading to the pressure transducer means.

15. A pressure transducer assembly as recited in claim 1 wherein the engagement means comprises a resilient, snap-fitting means for connecting electrical wiring to the assembly.

16. A pressure transducer assembly as recited in claim 15 wherein the resilient, snap-fitting means comprises an opening into the second chamber for receiving an electric wiring connector and at least one resilient portion of the housing for engaging an electric wiring connector and which is deformable for releasing such an electric wiring connector.

17. A pressure transducer assembly as recited in claim 1 further comprising a wiring connector means which engages the electrical conducting means in the second chamber for transmitting electric impulses generated by the pressure transducer means along electrical wiring to a monitoring means for displaying fluid pressure in fluid in the first chamber.

18. A pressure transducer assembly as recited in claim 17 wherein the electrical conducting means comprises electrical pins extending into the second chamber and the wiring connector means comprises a body having electrical pins engaging terminals and which slides into the second chamber and which engaging engages the electrical pins.

19. A pressure transducer assembly as recited in claim 1 wherein the pressure transducer means includes a temperature compensation circuit means for determining fluid pressure at the second sensed temperature of a fluid in the first chamber.

20. A pressure transducer assembly as recited in claim 1 wherein the inlet port and outlet port are axially aligned.

21. A disposable pressure transducer assembly for use in the invasive monitoring of blood pressure, the assembly comprising:

a housing defining a chamber therewithin and having an inlet port and an outlet port in fluid-flow communication with the chamber.

an electrically insulated intervening wall in the chamber separating the chamber into a first chamber and a second chamber wherein the first chamber is in fluid-flow communication with the inlet port and outlet port and the second chamber is separated from the first chamber by a fluid-tight seal;

a pressure transducer means secured in the first chamber in a depression on the electrically insulated intervening wall, which pressure transducer means is exposed to the first chamber for sensing and converting fluid pressure exhibited by a fluid in the first chamber into electrical impulses;

an electrically nonconductive, fluid pressure responsive media covering the pressure transducer means which separates the pressure transducer means from direct contact with fluid present in the first chamber;

electrical conducting means connected to the pressure transducer means for transmitting and receiving electrical impulses from the pressure transducer means and which extends through the intervening wall into the second chamber to provide a pathway for electricity between the pressure transducer means in the first chamber and the second chamber; and

receptor means on the housing for receiving and connecting the housing to electrical wiring means for powering the pressure transducer means and for transferring electrical impulses generated by the pressure transducer means and corresponding to determined pressures.

22. A disposable pressure transducer assembly as recited in claim 21 wherein the electrically nonconductive fluid pressure responsive media comprises silicone elastomer.

23. A disposable pressure transducer assembly as recited in claim 20 21 further comprising tubing connecting means on the inlet and outlet ports for connecting tubing to the housing.

24. A disposable pressure transducer assembly as recited in claim 21 wherein the electrical conducting means comprises a plurality of electrical conducting metal pins electrically interconnected to the pressure transducer means to transfer power to the pressure transducer means and to transfer away electric impulse signals corresponding to determined pressures.

25. A disposable pressure transducer assembly as recited in claim 21 wherein the electrically insulated intervening wall within the chamber comprises a polysulfone wall.

26. A disposable pressure transducer assembly as recited in claim 21 wherein the pressure transducer means comprises a monolithic silicon pressure sensor employing a four-terminal resistive element formed in a monocrystalline silicon diaphragm.

27. A disposable pressure transducer assembly as recited in claim 21 wherein the pressure transducer means monitors fluid pressure within the first chamber in the range from about -50 mmHg to +300 mmHg.

28. A disposable pressure transducer assembly as recited in claim 21 further comprising a clear lens means on the housing extending over the first chamber for viewing fluid and bubbles in the fluid within the first chamber.

29. A disposable pressure transducer assembly as recited in claim 28 wherein the clear lens means comprises a clear dome portion on the housing extending over at least a portion of the first chamber.

30. A disposable pressure transducer assembly as recited in claim 21 wherein the housing comprises a biocompatible polymeric material.

31. A disposable pressure transducer assembly as recited in claim 30 wherein the biocompatible polymeric material is selected from the group consisting of polycarbonate, polypropylene, polyethylene and polysulfone.

32. A disposable pressure transducer assembly as recited in claim 21 further comprising vent means on the housing and on the electrically insulated intervening wall for providing exposure to the atmosphere for the pressure transducer means.

33. A disposable pressure transducer assembly as recited in claim 32 wherein the vent means comprises an opening extending through the housing into the second chamber and aligned with an opening extending through the electrically insulated intervening wall and leading to the pressure transducer means.

34. A disposable pressure transducer assembly as recited in claim 21 further comprising a wiring connector means which engages the electrical conducting means in the second chamber for transmitting electrical impulses generated by the pressure transducer means along electrical wiring to a monitoring means for displaying fluid pressure in fluid in the first chamber.

35. A disposable pressure transducer assembly as recited in claim 34 wherein the electrical conducting means comprises electrical pins extending into the second chamber and the wiring connector means comprises a body having electrical pins engaging terminals and which slides into the second chamber and which engaging engages the electrical pins.

36. A disposable pressure transducer assembly as recited in claim 21 wherein the pressure transducer means includes a temperature compensation circuit means for determining fluid pressure at the sensed temperature of a fluid in the first chamber.

37. A disposable pressure transducer assembly as recited in claim 21 wherein the inlet port and outlet 171 are 173 ep port axially aligned.

38. A disposable pressure transducer assembly for invasively monitoring blood pressure comprising:

a housing comprised of polysulfone defining a chamber therewithin, having an inlet port and an outlet port in fluid-flow communication with the chamber and having a first aperture opening to the chamber;

an electrically insulated intervening wall in the chamber comprised of polysulfone which separates the chamber into a first chamber and a second chamber wherein the first chamber is in fluid-flow communication with the inlet port and outlet port and the second chamber having an opening through the housing and separated from the first chamber by a fluid-tight seal and the first aperture extends into the second chamber and aligns with a second aperture extending through the electrically insulated intervening wall;

a pressure transducer means secured in the first chamber in a depression on the electrically insulated intervening wall, which pressure transducer means is exposed to the first chamber for sensing and converting fluid pressure exhibited by a fluid in the first chamber into electrical impulses;

an electrically nonconductive fluid pressure responsive media comprising silicone elastomer covering the pressure transducer means which separates the pressure transducer means from direct contact with fluid present in the first chamber;

electrical conducting pins connected to the pressure transducer means for transmitting and receiving electrical impulses from the pressure transducer means and which extend through the intervening wall into the second chamber to provide a pathway for electricity between the pressure transducer means in the first chamber and the second chamber; and

snap-fitting resilient arms on the housing which combine with the opening through the housing into the second chamber which receives and connects the housing to electrical wiring means for powering the pressure transducer means and for transferring electrical impulses generated by the pressure transducer means and corresponding to determined pressures.

39. A disposable pressure transducer assembly as recited in claim 38 wherein the pressure transducer means comprises a monolithic silicon pressure sensor employing a four-terminal resistive element formed in a monocrystalline silicon diaphragm.

40. A disposable pressure transducer assembly as recited in claim 38 wherein the pressure transducer means monitors fluid pressure within the first chamber in the range from about -50 mmHg to +300 mmHg.

41. A disposable pressure transducer assembly as recited in claim 38 wherein the pressure transducer means includes a temperature compensation circuit means for determining fluid pressure at the sensed temperature of a fluid in the first chamber.

42. A disposable pressure transducer assembly as recited in claim 38 further comprising a clear lens means on the housing extending over the first chamber for viewing fluid and bubbles in the fluid within the first chamber.

43. A disposable pressure transducer assembly as recited in claim 42 wherein the clear lens means comprises a clear dome portion on the housing extending over at least a portion of the first chamber.

44. A disposable pressure transducer assembly as recited in claim 38 wherein the inlet por port and outlet port are axially aligned.

45. A disposable pressure transducer assembly for invasively monitoring blood pressure comprising:

a housing comprised of polysulfone with at least a portion of the housing forming a dome and extending over and defining a chamber with the housing, the housing including an inlet port and an outlet port in fluid-flow communication with the chamber and a first aperture opening to the chamber;

an electrically insulated intervening wall in the chamber comprised of polysulfone which separates the chamber into a first chamber and a second chamber wherein the first chamber is in fluid-flow communication with the inlet port and outlet port and the second chamber having an opening through the housing and separated from the first chamber by a fluid-tight seal and the first aperture extends into the second chamber and aligns with a second aperture extending through the electrically insulated intervening wall;

a pressure transducer means secured in the first chamber in a depression on the electrically insulated intervening wall, which pressure transducer means is exposed to the first chamber for sensing and converting fluid pressure exhibited by a fluid in the first chamber into electrical impulses;

an electrically nonconductive fluid pressure responsive media comprising silicone elastomer covering the pressure transducer means which separates the pressure transducer means from direct contact with fluid present in the first chamber.

electrical conducting pins connected to the pressure transducer means for transmitting and receiving electrical impulses from the pressure transducer means and which extend through the intervening wall into the second chamber to provide a pathway for electricity between the pressure transducer means in the first chamber and the second chamber; and

snap-fitting resilient arms on the housing which combine with the opening through the housing into the second chamber which receives and connects the housing to electrical wiring means for powering the pressure transducer means and for transferring electrical impulses generated by the pressure transducer means and corresponding to determined pressures.

46. A disposable pressure transducer assembly as recited in claim 45 wherein the pressure transducer means comprises a monolithic silicon pressure sensor employing a four-terminal resistive element formed in a monocrystalline silicon diaphragm.

47. A disposable pressure transducer assembly as recited in claim 45 wherein the pressure transducer means monitors fluid pressure within the first chamber in the range from about -50 mmHg to +300 mmHg.

48. A disposable pressure transducer assembly as recited in claim 45 wherein the pressure transducer means includes a temperature compensation circuit means for determining fluid pressure at the sensed temperature of a fluid in the first chamber.

49. A disposable pressure transducer assembly as recited in claim 45 wherein the inlet port and outlet port are axially aligned.

50. A pressure transducer assembly for monitoring pressure in a fluid comprising;

a housing defining a chamber and having an inlet port and an outlet port in fluid-flow communication with the chamber;

an insulated body sealed within the chamber which forms separate first and second chambers within the housing with the first chamber in fluid-flow communication with the inlet port and outlet port and adapted to be filled with fluid from the inlet port;

a pressure transducer means secured on the insulated body and exposed to pressure of fluid in the first chamber for determining and converting fluid pressure within a fluid adapted to be in the first chamber into electrical impulses;

temperature compensation means for compensating the sensed pressure in the fluid based upon the temperature of the fluid and correcting such sensed pressure;

a fluid pressure responsive media which is electrically nonconductive and which separates the pressure transducer means from any fluid present in the first chamber; and

an electrical conductor connected to the pressure transducer means.

51. A pressure transducer as described in claim 50 wherein the insulating body has an opening extending between the first and second chambers, said pressure transducer means is in communication with said opening and said fluid pressure responsive media is in said opening. 52. A pressure transducer as described in claim 51 wherein the fluid pressure responsive media is a polymeric material and the transducer is aligned

with the opening. 53. A pressure transducer assembly for monitoring pressure in a fluid comprising:

a housing having an inlet port and an outlet port;

means for forming a partition within the housing to provide separate first and second chambers within the housing with the first chamber in fluid-flow communication with the inlet port and outlet port and adapted to be filled with fluid from the inlet port, said housing having a portion through which fluid in the first chamber can be observed;

a pressure transducer carried by the partition and exposed to pressure of fluid in the first chamber for determining and converting fluid pressure within a fluid adapted to be in the first chamber into electrical impulses;

a fluid pressure responsive media which is electrically nonconductive and which separates the pressure transducer from any fluid present in the first chamber; and

an electrical conductor connected to the pressure transducer and extending from the pressure transducer. 54. A pressure transducer assembly for monitoring pressure in a fluid comprising;

a biocompatible housing having an inlet port and an outlet port;

means for forming a partition within the housing to provide separate first and second chambers within the housing with the first chamber in fluid-flow communication with the inlet port and outlet port, said housing having a portion through which fluid in the first chamber can be observed;

said partition having an opening extending between the first and second chambers;

a pressure transducer for sensing pressure of the fluid;

temperature compensation means for compensating the sensed pressure in the fluid based upon the temperature of the fluid and correcting such sensed pressure;

means for mounting the pressure transducer in said housing in communication with said opening whereby the pressure transducer is exposed to pressure of fluid adapted to be in the first chamber for determining and converting fluid pressure within a fluid in the first chamber into electrical impulses;

a biocompatible electrically nonconductive fluid pressure responsive media in said opening for separating the pressure transducer from any fluid present in the first chamber; and

an electrical conductor connected to the pressure transducer. 55. A pressure transducer as described in claim 54 wherein said partition is a nonconductor of electricity between the first and second chambers. 56. A pressure transducer as described in claim 54 wherein the transducer is aligned with said opening and supported by the partition. 57. A pressure transducer assembly for monitoring pressure in a fluid comprising:

a housing having an inlet port and an outlet port;

a source of I.V. solution;

flexible tubing connected to the source of I.V. solution and to the inlet port;

means for coupling the outlet port to the patient;

means for forming a partition within the housing to provide separate first and second chambers within the housing with the first chamber in fluid-flow communication with the inlet port and outlet port and adapted to be filled with fluid from the inlet port, said housing having a portion through which fluid in the first chamber can be observed;

a pressure transducer carried by the partition and exposed to pressure of fluid in the first chamber for determining and converting fluid pressure within a fluid adapted to be in the first chamber into electrical impulses;

a fluid pressure responsive media which is electrically nonconductive and which separates the pressure transducer from any fluid present in the first chamber; and

an electrical conductor connected to the pressure transducer and extending

from the pressure transducer. 58. A pressure transducer assembly for monitoring pressure in a fluid comprising:

a biocompatible housing having an inlet port and an outlet port;

means for forming a partition within the housing to provide separate first and second chambers within the housing with the first chamber in fluid-flow communication with the inlet port and outlet port and adapted to be filled with fluid from the inlet port;

a pressure transducer carried by the partition and exposed to pressure of fluid in the first chamber for determining and converting fluid pressure within a fluid adapted to be in the first chamber into electrical impulses;

a biocompatible fluid pressure responsive media which is electrically nonconductive and which separates the pressure transducer from any fluid present in the first chamber; and

an electrical conductor connected to the pressure transducer and extending from the pressure transducer.