Pulse oximetry sensor adapter

• US 20060189859A1
• Filed: 01/27/2006
• Published: 08/24/2006
• Est. Priority Date: 02/11/1998
• Status: Active Grant

• Current Assignee: David Tobler, Massi E. Kiani, Robert A. Smith
• Original Assignee: David Tobler, Massi E. Kiani, Robert A. Smith
• Inventors: Kiani, Massi E., Smith, Robert A., Tobler, David R.
• Granted Patent: US 7,844,313 B2
• Time in Patent Office: Days
• US Class Current: 600/323
• CPC Class Codes: A61B 2562/222 Electrical cables or leads therefor, e.g. coaxial cables or ribbon cables
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: Y10S 439/909 Medical use or attached to human body

Abstract

An adapter allows the interconnection of a sensor originating from one manufacturer to be coupled with conventionally incompatible monitors originating from other manufacturers to form a properly functioning pulse oximetry system. The adapter matches a sensor driver in a monitor to the current requirements and light source configuration of a sensor. The adapter also matches a sensor'"'"'s light detector signal level to the dynamic range requirements of a monitor preamplifier. Further, the adapter provides compatible sensor calibration, sensor type and security information to a monitor. The adapter may have a self-contained power source or it may derive power from the monitor, allowing both passive and active adapter components. The adapter is particular suited as an adapter cable, replacing a conventional patient cable or sensor cable as the interconnection between a sensor to a monitor in a pulse oximetry system.

Claims

1. A universal adapter configured to connect one sensor from a variety of possible sensors to one monitor from a variety of possible monitors to create a pulse oximetry system, the universal adapter comprising:

a first connector adapter configured for attachment to a monitor;

a second connector adapter configured for attachment to a sensor; and

a sensor adapter cable coupled between the first connector adapter and the second connector adapter, wherein the sensor adapter cable comprises;

a monitor selector configured to sense a drive configuration or drive levels of the monitor;

a sensor selector configured to sense a light emitting diode configuration or presence of an information element in the sensor;

a plurality of adapter elements configured to modify signals between the monitor and the sensor for compatible operations;

a first switching circuit configured to couple a selected adapter element to the monitor based on outputs from the monitor selector and the sensor selector, wherein the selected adapter element is one of the plurality of adapter elements; and

a second switching circuit configured to couple the selected adapter element to the sensor.

2. The universal adapter of claim 1 wherein the sensor adapter cable has generic connectors at each end with predetermined signal pinouts, the first connector adapter is a cross-wired cable with a generic connector at one end for mating with the first generic connector of the sensor adapter cable and a specific connector at another end for mating with a specific type of monitor, and the second connector adaptor is a cross-wired cable with a generic connector at one end for mating with the second generic connector of the sensor adapter cable and a specific connector at another end for mating with a specific type of sensor.

3. The universal adapter of claim 2 wherein the monitor selector tests signal lines from the first generic connector of the sensor adapter cable to determine the drive configuration or the drive levels of the monitor while the sensor selector tests signal lines from the second generic connector of the sensor adapter cable to determine the light emitting diode configuration or presence of the information element in the sensor.

4. The universal adapter of claim 1 wherein the first switching circuit and the second switching circuit are bi-directional multiplexers.

5. The universal adapter of claim 1 wherein one of the plurality of adapter elements is a straight-through adapter for coupling a monitor with a normally compatible sensor.

6. The universal adapter of claim 1 wherein the monitor selector determines the drive configuration based on three signal lines connectable to the monitor, and the monitor selector comprises three differential amplifiers with each of the differential amplifiers having inputs coupled across a unique pair of the three signal lines.

7. The universal adapter of claim 1 wherein the sensor selector determines the light emitting diode configuration based on three signal lines connectable to the sensor, and the sensor selector comprises a voltage source that selectively connects to one of the three signal lines while two amplifiers selectively connect to the remaining two of the three signal lines.

8. A method to connect one sensor from a variety of possible sensors to one monitor from a variety of possible monitors, the method comprising:

attaching a monitor to a first end of an adapter cable;

attaching a sensor to a second end of the adapter cable;

sensing a driver configuration of the monitor based on a first set of signal lines at the first end of the adapter cable;

sensing a light emitting diode configuration of the sensor based on a second set of signal lines at the second end of the adapter cable;

selecting an adapter element from a plurality of adapter elements in the adapter cable to interface the first set of signals with the second set of signals for compatible operation.

9. The method of claim 8 wherein attaching the monitor to the first end of the adapter cable comprises:

using an attachment cable with a specific connector at one end and a generic connector at another end, wherein the specific connector mates with a monitor connector and the generic connector mates with an adapter connector at the first end of the adapter cable; and

cross-wiring one or more cable wires between the specific connector and the generic connector in the attachment cable to match predetermined pinouts in the adapter connector.

10. The method of claim 8 wherein attaching the sensor to the second end of the adapter cable comprises:

using an attachment cable with a specific connector at one end and a generic connector at another end, wherein the specific connector mates with a sensor connector and the generic connector mates with an adapter connector at the second end of the adapter cable; and

cross-wiring one or more cable wires between the specific connector and the generic connector in the attachment cable to match predetermined pinouts in the adapter connector.

11. The method claim 8 wherein sensing the driver configuration of the monitor comprises detecting a differential voltage across at least one pair of signal lines in the first set of signal lines.

12. The method of claim 8 wherein sensing the light emitting diode configuration of the sensor comprises driving the signal lines in the second set of signal lines one at a time while detecting for current in the remaining signal lines.

13. The method of claim 8 wherein the first set of signal lines and the second set of signal lines comprise three signal lines each.

14. The method of claim 8 wherein bi-directional switches couple the selected adapter element to the appropriate signal lines.

15. A universal adapter comprising:

means for attaching a monitor to a first standard connector at a first end of a sensor adapter cable;

means for attaching a sensor to a second standard connector at a second end of the sensor adapter cable;

means for testing a first set of signal lines in the first standard connector to determine monitor type;

means for testing a second set of signal lines in the second standard connector to determine sensor type; and

means for connecting the first set of signal lines and the second set of signal lines for compatible operation between the monitor and the sensor.