Pressure-attached presenting part fetal pulse oximetry sensor

• US 5,776,058 A
• Filed: 08/13/1996
• Issued: 07/07/1998
• Est. Priority Date: 08/13/1996
• Status: Expired due to Term

• Current Assignee: Nellcor Puritan Bennett Incorporated (Medtronic Plc)
• Original Assignee: Nellcor Puritan Bennett Incorporated (Medtronic Plc)
• Inventors: Warring, Jessica, Palmer, Phillip S., Levinson, Mitchell, Nierlich, Steven L.
• Primary Examiner(s): Nasser, Robert L.
• Assistant Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US08/701,351
• Time in Patent Office: 693 Days
• Field of Search: 128/633, 128/634, 128/664, 128/665, 600/338, 600/339, 600/313, 600/473, 600/476
• US Class Current: 600/338
• CPC Class Codes: A61B 2503/02 Foetus
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/1464 specially adapted for foetal tissue
• CPC Class Codes: A61B 5/6859 with multiple distal splines
• CPC Class Codes: A61B 5/6882 Anchoring means
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure

Abstract

A presenting part fetal pulse oximeter sensor which does not penetrate the fetus'"'"' skin, and does not rely on a vacuum for attachment is provided. The fetal sensor of the present invention is held in place by pressure applied to the fetus by a number of different mechanisms. In one embodiment, the sensor is held in place against the fetus by a rigid rod, with the pressure being applied by the physician or technician'"'"'s hand on the rod. This type of a sensor is useful for spot-checking, where continuous monitoring is not needed. In another embodiment, a pre-loaded spring is coupled between the rod and the sensor head to prevent too much pressure being applied by the user.

Claims

1. A perinatal pulse oximeter sensor for temporary application to a fetus and providing a signal corresponding to blood oxygen saturation, comprising:

a sensor head having a fetus engaging surface for engagement with a presenting part of said fetus with applied pressure;

light emitting means connected to said sensor head for emitting light of at least two wavelengths directed in a predetermined direction at said presenting part of said fetus;

light detecting means mounted in said sensor head for collecting light from said light emitting means scattered through said fetus, and providing said signal corresponding to blood oxygen saturation; and

a rigid member having a longitudinal axis connected to said sensor head with said longitudinal axis aligned with said predetermined direction having sufficient length for inserting said sensor head into a vagina and for applying said pressure to said sensor head from external to said vagina.

2. The sensor of claim 1 wherein said light emitting means and light detecting means comprise fiber optic cables.

3. The sensor of claim 1 further comprising a biasing means, coupled between said rigid member and said sensor head, for regulating the amount of force applied to said sensor head.

4. The sensor of claim 3 wherein said biasing means is a pre-loaded spring.

5. A perinatal pulse oximeter sensor for temporary application to a fetus and providing a signal corresponding to blood oxygen saturation, comprising:

a sensor head having a fetus engaging surface for engagement with a presenting part of said fetus with applied pressure;

light emitting means connected'"'"' to said sensor head for emitting light of at least two wavelengths directed at said presenting part of said fetus;

light detecting means mounted in said sensor head for collecting light from said light emitting means scattered through said fetus, and providing said signal corresponding to blood oxygen saturation; and

a rigid housing having sufficient length to insert said sensor head into a vagina;

biasing means, coupled between said housing and said sensor head, for applying said pressure to said sensor head.

6. The sensor of claim 5 wherein said biasing means comprises a spring between said housing and said sensor head.

7. The sensor of claim 5 wherein said biasing means comprises a spring internal to said housing for extending said sensor head partially out of said housing.

8. The sensor of claim 7 wherein said spring is pre-loaded.